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1.  Cognitive factors associated with adherence to oral anti-estrogen therapy: Results from the Cognition in the Study of Tamoxifen and Raloxifene (Co-STAR) Study 
Little is known about the cognitive factors associated with adherence to anti-estrogen therapy. Our objective was to investigate the association between domain-specific cognitive function and adherence among women in a clinical prevention trial of oral anti-estrogen therapies. We performed a secondary analysis of Co-STAR, an ancillary study of the STAR breast cancer prevention trial in which postmenopausal women at increased breast cancer risk were randomized to tamoxifen or raloxifene. Co-STAR enrolled non-demented participants ≥65 years old to compare treatment effects on cognition. The cognitive battery assessed global cognitive function (Modified Mini-Mental State Exam), and specific cognitive domains of verbal knowledge, verbal fluency, figural memory, verbal memory, attention and working memory, spatial ability, and fine motor speed. Adherence was defined by a ratio of actual time taking therapy per protocol ≥80% of expected time. Logistic regression was used to evaluate the association between cognitive test scores and adherence to therapy. The mean age of the 1,331 Co-STAR participants was 67.2±4.3 years. Mean 3MS score was 95.1 (4.7) and 14% were non-adherent. In adjusted analyses, the odds of non-adherence were lower for those with better scores on verbal memory [OR (95% CI): 0.75 (0.62, 0.92)]. Larger relative deficits in verbal memory compared to verbal fluency were also associated with non-adherence [1.28 (1.08, 1.51)]. Among non-demented older women, subtle differences in memory performance were associated with medication adherence. Differential performance across cognitive domains may help identify persons at greater risk for poor adherence.
doi:10.1158/1940-6207.CAPR-13-0165
PMCID: PMC3924583  PMID: 24253314
adherence; cancer; cognition; elderly; tamoxifen; women
2.  Effect of structured physical activity on prevention of major mobility disability in older adults: the LIFE Study randomized clinical trial 
JAMA  2014;311(23):2387-2396.
SUMMARY
Importance
In older adults reduced mobility is common and is an independent risk factor for morbidity, hospitalization, disability, and mortality. Limited evidence suggests that physical activity may help prevent mobility disability; however, there are no definitive clinical trials examining if physical activity prevents or delays mobility disability.
Objective
To test the hypothesis that a long-term structured physical activity program is more effective than a health education program (also referred to as a successful aging program) in reducing the risk of major mobility disability.
Design, Setting, and Participants
The Lifestyle Interventions and Independence for Elders (LIFE) study was a multicenter, randomized trial that enrolled participants between February 2010 and December 2011, who participated for an average of 2.6 years. Follow-up ended in December 2013. Outcome assessors were blinded to the intervention assignment. Participants were recruited from urban, suburban and rural communities at 8 field centers throughout the US. We randomized a volunteer sample of 1,635 sedentary men and women aged 70–89 years who had physical limitations, defined as a score on the Short Physical Performance Battery of 9 or below, but were able to walk 400 m.
Interventions
Participants were randomized to a structured moderate intensity physical activity program (n=818) done in a center and at home that included including aerobic, resistance and flexibility training activities or to a health education program (n=817) consisting of workshops on topics relevant to older adults and upper extremity stretching exercises.
Main Outcomes and Measures
The primary outcome was major mobility disability objectively defined by loss of ability to walk 400 m.
Results
Incident major mobility disability occurred in 30.1% (n=246/818) of physical activity and 35.5% (n=290/817) of health education participants (HR=0.82, 95%CI=0.69–0.98, p=0.03). Persistent mobility disability was experienced by 120/818 (14.7%) physical activity and 162/817 (19.8%) health education participants (HR=0.72; 95%CI=0.57–0.91; p=0.006). Serious adverse events were reported by 404/818 (49.4%) of the physical activity and 373/817 (45.7%) of the health education participants (Risk Ratio=1.08; 95%CI=0.98–1.20).
Conclusions and Relevance
A structured moderate intensity physical activity program, compared with a health education program, reduced major mobility disability over 2.6 years among older adults at risk of disability. These findings suggest mobility benefit from such a program in vulnerable older adults.
Registration
ClinicalsTrials.gov identifier NCT01072500.
doi:10.1001/jama.2014.5616
PMCID: PMC4266388  PMID: 24866862
3.  PERFORMANCE OF A COMPUTER-BASED ASSESSMENT OF COGNITIVE FUNCTION MEASURES IN TWO COHORTS OF SENIORS 
International journal of geriatric psychiatry  2013;28(12):10.1002/gps.3949.
Background
Computer-administered assessment of cognitive function is being increasingly incorporated in clinical trials, however its performance in these settings has not been systematically evaluated.
Design
The Seniors Health and Activity Research Program (SHARP) pilot trial (N=73) developed a computer-based tool for assessing memory performance and executive functioning. The Lifestyle Interventions and Independence for Seniors (LIFE) investigators incorporated this battery in a full scale multicenter clinical trial (N=1635). We describe relationships that test scores have with those from interviewer-administered cognitive function tests and risk factors for cognitive deficits and describe performance measures (completeness, intra-class correlations).
Results
Computer-based assessments of cognitive function had consistent relationships across the pilot and full scale trial cohorts with interviewer-administered assessments of cognitive function, age, and a measure of physical function. In the LIFE cohort, their external validity was further demonstrated by associations with other risk factors for cognitive dysfunction: education, hypertension, diabetes, and physical function. Acceptable levels of data completeness (>83%) were achieved on all computer-based measures, however rates of missing data were higher among older participants (odds ratio=1.06 for each additional year; p<0.001) and those who reported no current computer use (odds ratio=2.71; p<0.001). Intra-class correlations among clinics were at least as low (ICC≤0.013) as for interviewer measures (ICC≤0.023), reflecting good standardization. All cognitive measures loaded onto the first principal component (global cognitive function), which accounted for 40% of the overall variance.
Conclusion
Our results support the use of computer-based tools for assessing cognitive function in multicenter clinical trials of older individuals.
doi:10.1002/gps.3949
PMCID: PMC3775886  PMID: 23589390
Cognitive function; Clinical trial; Performance measures
4.  Omega-3 fatty acids and domain-specific cognitive aging 
Neurology  2013;81(17):1484-1491.
Objective:
To test the hypothesis that higher levels of red blood cell (RBC) docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) have a protective association with domain-specific cognitive function in women aged 65 years and older.
Methods:
A total of 2,157 women with normal cognition enrolled in a clinical trial of postmenopausal hormone therapy were followed with annual cognitive testing for a median of 5.9 years. In this retrospective cohort study, we assessed the relationship between prerandomization RBC DHA + EPA levels and a) cognitive measures at baseline, and b) cognitive change over time. Endpoints were composite cognitive function and performance in 7 cognitive domains: fine motor speed, verbal memory, visual memory, spatial ability, verbal knowledge, verbal fluency, and working memory.
Results:
After adjustment for demographic, clinical, and behavioral characteristics, no significant (p < 0.01) cross-sectional cognitive differences were found between women in the high and low DHA + EPA tertiles at the time of the first annual cognitive battery. In addition, no significant (p < 0.01) differences were found between the high and low DHA + EPA tertiles in the rate of cognitive change over time.
Conclusions:
We did not find an association between RBC DHA + EPA levels and age-associated cognitive decline in a cohort of older, dementia-free women.
doi:10.1212/WNL.0b013e3182a9584c
PMCID: PMC3888166  PMID: 24068783
5.  Impact of Weight Loss on Ankle-Brachial Index and Inter-Artery Blood Pressures in Overweight and Obese Adults with Diabetes 
Obesity (Silver Spring, Md.)  2014;22(4):1032-1041.
Objective
To assess whether weight loss improves markers of peripheral artery disease and vascular stenosis.
Design and Methods
The Action for Health in Diabetes randomized clinical trial compared intensive lifestyle intervention (ILI) for weight loss to a control condition of diabetes support and education (DSE) in overweight or obese adults with type 2 diabetes. Annual ankle and brachial blood pressures over four years were used compute ankle-brachial indices (ABIs) and to assess inter-artery blood pressure differences in 5018 participants.
Results
ILI, compared to DSE, produced 7.8% (Year 1) to 3.6% (Year 4) greater weight losses. These did not affect prevalence of low (<0.90) ABI (3.60% in DSE versus 3.14% in ILI; p=0.20) or elevated (>1.40) ABI (7.52% in DSE versus 7.59% in ILI: p=0.90), but produced smaller mean (SE) maximum inter-artery systolic blood pressure differences among ankle sites [19.7 (0.2) mmHg for ILI versus 20.6 (0.2) mmHg for DSE (p<0.001)] and between arms [5.8 (0.1) mmHg for ILI versus 6.1 (0.1) mmHg for DSE (p=0.01)].
Conclusions
Four years of intensive behavioral weight loss intervention did not significantly alter prevalence of abnormal ABI, however it did reduce differences in systolic blood pressures among arterial sites.
doi:10.1002/oby.20658
PMCID: PMC3968218  PMID: 24174392
Peripheral artery disease; Weight loss; Diabetes
6.  Do weight loss and adherence cluster within behavioral treatment groups? 
Obesity (Silver Spring, Md.)  2013;22(3):638-644.
Objective
Weight loss programs are often conducted in a group format, but it is unclear whether weight losses or adherence cluster within treatment group and whether characteristics of the group (e.g. size or homogeneity) affect outcomes. We examined these questions within Look AHEAD, a multicenter study of the effects of an intensive lifestyle intervention (ILI) in overweight/obese individuals with type 2 diabetes.
Design and Methods
Weight losses and adherence (attendance, use of meal replacement products, and minutes of activity) were examined over one year of intervention in 2329 ILI participants in 209 treatment groups, which all received the same weight loss program.
Results
Weight losses did not cluster among members of a treatment group (intra-class correlation [ICC] of .007), whereas measures of adherence had small/moderate clustering (ICCs of .05–.11). The 209 groups varied in weight losses, with a mean of 8.64 % (SD=2.35 %, interquartile range=6.82%, 10.32%), but neither size nor baseline homogeneity of members affected the outcome.
Conclusions
Although these findings suggest that it may not be necessary to control for clustering in behavioral weight loss studies, they also indicate that merely treating individuals in groups is not sufficient to harness social influences on weight loss.
doi:10.1002/oby.20526
PMCID: PMC3859866  PMID: 23804576
behavioral weight loss; clustering of outcomes; treatment groups
7.  The LIFE Cognition Study: design and baseline characteristics 
Observational studies have shown beneficial relationships between exercise and cognitive function. Some clinical trials have also demonstrated improvements in cognitive function in response to moderate–high intensity aerobic exercise; however, these have been limited by relatively small sample sizes and short durations. The Lifestyle Interventions and Independence for Elders (LIFE) Study is the largest and longest randomized controlled clinical trial of physical activity with cognitive outcomes, in older sedentary adults at increased risk for incident mobility disability. One LIFE Study objective is to evaluate the effects of a structured physical activity program on changes in cognitive function and incident all-cause mild cognitive impairment or dementia. Here, we present the design and baseline cognitive data. At baseline, participants completed the modified Mini Mental Status Examination, Hopkins Verbal Learning Test, Digit Symbol Coding, Modified Rey–Osterrieth Complex Figure, and a computerized battery, selected to be sensitive to changes in speed of processing and executive functioning. During follow up, participants completed the same battery, along with the Category Fluency for Animals, Boston Naming, and Trail Making tests. The description of the mild cognitive impairment/dementia adjudication process is presented here. Participants with worse baseline Short Physical Performance Battery scores (prespecified at ≤7) had significantly lower median cognitive test scores compared with those having scores of 8 or 9 with modified Mini Mental Status Examination score of 91 versus (vs) 93, Hopkins Verbal Learning Test delayed recall score of 7.4 vs 7.9, and Digit Symbol Coding score of 45 vs 48, respectively (all P<0.001). The LIFE Study will contribute important information on the effects of a structured physical activity program on cognitive outcomes in sedentary older adults at particular risk for mobility impairment. In addition to its importance in the area of prevention of cognitive decline, the LIFE Study will also likely serve as a model for exercise and other behavioral intervention trials in older adults.
doi:10.2147/CIA.S65381
PMCID: PMC4154884  PMID: 25210447
exercise; physical activity; older adults; dementia
8.  Recruitment of young adults into a randomized controlled trial of weight gain prevention: message development, methods, and cost 
Trials  2014;15(1):326.
Background
Young adulthood (age 18 to 35) is a high-risk period for unhealthy weight gain. Few studies have recruited for prevention of weight gain, particularly in young adults. This paper describes the recruitment protocol used in the Study of Novel Approaches to Prevention (SNAP).
Methods
We conducted extensive formative work to inform recruitment methods and message development. We worked with a professional marketing firm to synthesize major themes and subsequently develop age-appropriate messages for recruitment. A variety of approaches and channels were used across two clinical centers to recruit young adults who were normal or overweight (body mass index (BMI) 21 to 30 kg/m2) for a 3-year intervention designed to prevent weight gain. We tracked recruitment methods, yields, and costs by method. Logistic regression was used to identify recruitment methods that had the highest relative yield for subgroups of interest with covariate adjustments for clinic.
Results
The final sample of 599 participants (27% minority, 22% male) was recruited over a 19-month period of sustained efforts. About 10% of those who initially expressed interest via a screening website were randomized. The most common reason for ineligibility was already being obese (BMI >30 kg/m2). The top two methods for recruitment were mass mailing followed by email; together they were cited by 62% of those recruited. Television, radio, paid print advertising, flyers and community events each yielded fewer than 10% of study participants. Email was the most cost-effective method per study participant recruited.
Conclusions
These findings can guide future efforts to recruit young adults and for trials targeting weight gain prevention.
Trial registration
ClinicalTrials.gov NCT01183689 (registered 13 August 2010).
doi:10.1186/1745-6215-15-326
PMCID: PMC4150977  PMID: 25128185
weight gain prevention; young adults; recruitment methods; cost
9.  Long Term Effects on Cognitive Function of Postmenopausal Hormone Therapy Prescribed to Women Aged 50–55 Years 
JAMA internal medicine  2013;173(15):10.1001/jamainternmed.2013.7727.
Background
Postmenopausal hormone therapy with conjugated equine estrogens (CEE) may adversely affect older women’s cognitive function. It is not known whether this extends to younger women.
Methods
1,326 postmenopausal women, who had begun treatment in two randomized placebo-controlled clinical trials of hormone therapy when aged 50–55 years, were assessed with an annual telephone-administered cognitive battery that included measures of global (primary outcome) and domain-specific cognitive functions (verbal memory, attention, executive function, verbal fluency, and working memory). The clinical trials in which they participated had compared 0.625 mg CEE with or without 2.5 mg medroxyprogesterone acetate (MPA) over an average of 7.0 years. Cognitive testing was conducted an average of 7.2 years following the end of the trials, when women had mean age 67.2 years, and repeated one year later.
Results
Global cognitive function scores from women who had been assigned to CEE-based therapies were similar to those from women assigned to placebo: mean [95% confidence interval] intervention effect of 0.02 [−0.08,0.12]standard deviation units (p=0.66). Similarly, no overall differences were found for any individual cognitive domain (all p>0.15). Pre-specified subgroup analyses found some evidence that CEE-based therapies may have adversely affected verbal fluency among women who had prior hysterectomy or prior use of hormone therapy: mean treatment effects of −0.17 [−0.33, −0.02] and −0.25 [−0.42, −0.08], respectively, however this may be a chance finding. We are not able to address whether initiating hormone therapy during the menopause and maintaining therapy until any symptoms are passed affects cognitive function, either in the short or longer term.
Conclusions
CEE-based therapies produced no overall sustained benefit or risk to cognitive function when administered to postmenopausal women aged 50–55 years.
doi:10.1001/jamainternmed.2013.7727
PMCID: PMC3844547  PMID: 23797469
10.  Intensive Weight Loss Intervention in Individuals Ages 65 Years or Older: Results from the Look AHEAD Type 2 Diabetes Trial 
OBJECTIVES
To compare the relative effects of four years of intensive lifestyle intervention on weight, fitness, and cardiovascular disease risk factors among older versus younger individuals
DESIGN
A randomized controlled clinical trial
SETTING
16 US clinical sites
PARTICIPANTS
Individuals with type 2 diabetes: 1,053 aged 65–76 years and 4,092 aged 45–64 years
INTERVENTIONS
An intensive behavioral intervention designed to promote and maintain weight loss through caloric restriction and increased physical activity compared to a condition of diabetes support and education.
MEASUREMENTS
Standardized assessments of weight, fitness (based on graded exercise testing), and cardiovascular disease risk factors
RESULTS
Across four years, older individuals had greater intervention-related mean weight losses than younger participants, 6.2% versus 5.1% (interaction p=0.006) and comparable relative mean increases in fitness, 0.56 versus 0.53 metabolic equivalents (interaction p=0.72). These benefits were seen consistently across subgroups of older adults formed by many demographic and health factors. Among a panel of age-related health conditions, only self-reported worsening vision was associated with poorer intervention-related weight loss in older individuals. The intensive lifestyle intervention produced mean increases in high density lipoprotein cholesterol (2.03 mg/dl; p<0.001) and decreases in glycated hemoglobin (0.21%; p<0.001) and waist girth (3.52 cc; p<0.001) across 4 years that were at least as large in older compared to younger individuals.
CONCLUSION
Intensive lifestyle intervention targeting weight loss and increased physical activity is effective in overweight and obese older individuals to produce sustained weight loss and improvements in fitness and cardiovascular risk factors.
doi:10.1111/jgs.12271
PMCID: PMC4123658  PMID: 23668423
Behavioral intervention; Weight loss; Physical activity; Type 2 diabetes mellitus; Cardiovascular disease risk factors
11.  DEMOGRAPHIC AND HEALTH FACTORS ASSOCIATED WITH ENROLLMENT IN POST-TRIAL STUDIES: THE WOMEN’S HEALTH INITIATIVE HORMONE THERAPY TRIALS 
Clinical trials (London, England)  2013;10(3):463-472.
Background
After clinical trials end, continued follow-up of the assembled cohort often is desirable for additional research. Factors influencing participants’ decisions to consent to additional follow-up and how these shape post-trial cohorts have not been broadly studied.
Purpose
We examined how two re-enrollment campaigns and the passage of time altered features of the post-trial cohorts compared with the original Women’s Health Initiative Hormone Therapy clinical trials.
Methods
We examined associations that markers of socio-demography, health, lifestyle and on-trial experiences had with re-enrollment and contrasted the characteristics of successive post-trial cohorts with those of the original enrollees.
Results
The post-trial enrollment campaigns re-enrolled 81.1% and 82.5% of available women, respectively. Women who re-enrolled tended to have better health characteristics than those not re-enrolled. Compared to women of comparable age in the original cohort, women retained for the second post-trial follow-up less often had a history of cardiovascular disease [odds ratio OR=0.36], hypertension [OR=0.57], diabetes [OR=0.59], or measured cognitive deficit [OR=0.40]. These women more often had graduated from high school [OR=1.72] and had participated in other WHI trials [OR=1.76].
Limitations
We have examined experience with creating follow-up cohorst from participants in a single study. Thus, our findings may not apply to other cohorts and protocols.
Conclusions
Post-trial enrollment in follow-up studies can be successful; however the characteristics of the resulting cohort may differ substantially from the originally assembled group of trial participants. Collection during the original trial of potential predictors of differential re-enrollment may facilitate re-enrollment.
doi:10.1177/1740774513477931
PMCID: PMC4102257  PMID: 23480899
Post-trial follow-up; Retention; Missing data
12.  The rationale, design, and baseline characteristics of the Women’s Health Initiative Memory Study of Younger Women (WHIMS-Y) 
Brain research  2013;1514:3-11.
The Women’s Health Initiative Memory Study-Younger (WHIMS-Y) was designed to assess the effect of prior random assignment to hormone therapy (HT) (conjugated equine estrogen (CEE) alone or CEE plus medroxyprogesterone acetate (MPA)) on global cognitive function in younger middle-aged women relative to placebo. WHIMS-Y was an ancillary study to the Women’s Health Initiative (WHI) HT trial and enrolled 1361 women who were aged 50-54 years and postmenopausal at WHI enrollment. WHIMS-Y will examine whether an average of 5.4 years of HT during early menopause has longer term protective effects on global cognitive function and if these effects vary by regimen, time between menopause and study initiation, and prior use of HT. We present the study rationale and design. We describe enrollment, adherence to assigned WHI therapy, and compare risk factor characteristics of the WHIMS-Y cohort at the time of WHI enrollment to similar aged women in the WHI HT who did not enroll in WHIMS-Y. Challenges of WHIMS-Y include lower than expected and differential enrollment. Strengths of WHIMS-Y include balance in baseline risk factors between treatment groups, standardized and masked data collection, and high rates of retention and on-trial adherence and exposure. In addition, the telephone-administered cognitive battery showed adequate construct validity. WHIMS-Y provided an unprecedented chance to examine the hypothesis that HT may have protective effects on cognition in younger postmenopausal women aged 50-54 years. Integrated into the WHI, WHIMS-Y optimized the experience of WHI investigators to ensure high retention and excellent quality assurance across sites.
doi:10.1016/j.brainres.2013.03.047
PMCID: PMC3684042  PMID: 23578696
Postmenopausal hormone therapy; Cognitive function; Aging
13.  Four-Year Analysis of Cardiovascular Disease Risk Factors, Depression Symptoms, and Antidepressant Medicine Use in the Look AHEAD (Action for Health in Diabetes) Clinical Trial of Weight Loss in Diabetes 
Diabetes Care  2013;36(5):1088-1094.
OBJECTIVE
To study the association of depressive symptoms or antidepressant medicine (ADM) use with subsequent cardiovascular disease (CVD) risk factor status in the Look AHEAD (Action for Health in Diabetes) trial of weight loss in type 2 diabetes.
RESEARCH DESIGN AND METHODS
Participants (n = 5,145; age [mean ± SD] 58.7 ± 6.8 years; BMI 35.8 ± 5.8 kg/m2) in two study arms (intensive lifestyle [ILI], diabetes support and education [DSE]) completed the Beck Depression Inventory (BDI), reported ADM use, and were assessed for CVD risk factors at baseline and annually for 4 years. Risk factor–positive status was defined as current smoking, obesity, HbA1c >7.0% or insulin use, and blood pressure or cholesterol not at levels recommended by expert consensus panel or medicine to achieve recommended levels. Generalized estimating equations assessed within-study arm relationships of elevated BDI score (≥11) or ADM use with subsequent year CVD risk status, controlled for demographic variables, CVD history, diabetes duration, and prior CVD risk status.
RESULTS
Prior year elevated BDI was associated with subsequent CVD risk factor–positive status for the DSE arm (A1C [odds ratio 1.30 (95% CI 1.09–1.56)]; total cholesterol [0.80 (0.65–1.00)]; i.e., protective from high total cholesterol) and the ILI arm (HDL [1.40 (1.12–1.75)], triglyceride [1.28 (1.00–1.64)]). Prior year ADM use predicted subsequent elevated CVD risk status for the DSE arm (HDL [1.24 (1.03–1.50)], total cholesterol [1.28 (1.05–1.57)], current smoking [1.73 (1.04–2.88)]) and for the ILI arm (A1C [1.25 (1.08–1.46)], HDL [1.32 (1.11–1.58)], triglycerides [1.75 (1.43–2.14)], systolic blood pressure [1.39 (1.11–1.74)], and obesity [1.46 (1.22–2.18)]).
CONCLUSIONS
Aggressive monitoring of CVD risk in diabetic patients with depressive symptoms or who are treated with ADM may be warranted.
doi:10.2337/dc12-1871
PMCID: PMC3631821  PMID: 23359362
14.  Structural Equation Modeling for Analyzing Erythrocyte Fatty Acids in Framingham 
Research has shown that several types of erythrocyte fatty acids (i.e., omega-3, omega-6, and trans) are associated with risk for cardiovascular diseases. However, there are complex metabolic and dietary relations among fatty acids, which induce correlations that are typically ignored when using them as risk predictors. A latent variable approach could summarize these complex relations into a few latent variable scores for use in statistical models. Twenty-two red blood cell (RBC) fatty acids were measured in Framingham (N = 3196). The correlation matrix of the fatty acids was modeled using structural equation modeling; the model was tested for goodness-of-fit and gender invariance. Thirteen fatty acids were summarized by three latent variables, and gender invariance was rejected so separate models were developed for men and women. A score was developed for the polyunsaturated fatty acid (PUFA) latent variable, which explained about 30% of the variance in the data. The PUFA score included loadings in opposing directions among three omega-3 and three omega-6 fatty acids, and incorporated the biosynthetic and dietary relations among them. Whether the PUFA factor score can improve the performance of risk prediction in cardiovascular diseases remains to be tested.
doi:10.1155/2014/160520
PMCID: PMC4052884  PMID: 24959197
15.  Influence of Type 2 Diabetes on Brain Volumes and Changes in Brain Volumes 
Diabetes Care  2012;36(1):90-97.
OBJECTIVE
To study how type 2 diabetes adversely affects brain volumes, changes in volume, and cognitive function.
RESEARCH DESIGN AND METHODS
Regional brain volumes and ischemic lesion volumes in 1,366 women, aged 72–89 years, were measured with structural brain magnetic resonance imaging (MRI). Repeat scans were collected an average of 4.7 years later in 698 women. Cross-sectional differences and changes with time between women with and without diabetes were compared. Relationships that cognitive function test scores had with these measures and diabetes were examined.
RESULTS
The 145 women with diabetes (10.6%) at the first MRI had smaller total brain volumes (0.6% less; P = 0.05) and smaller gray matter volumes (1.5% less; P = 0.01) but not white matter volumes, both overall and within major lobes. They also had larger ischemic lesion volumes (21.8% greater; P = 0.02), both overall and in gray matter (27.5% greater; P = 0.06), in white matter (18.8% greater; P = 0.02), and across major lobes. Overall, women with diabetes had slightly (nonsignificant) greater loss of total brain volumes (3.02 cc; P = 0.11) and significant increases in total ischemic lesion volumes (9.7% more; P = 0.05) with time relative to those without diabetes. Diabetes was associated with lower scores in global cognitive function and its subdomains. These relative deficits were only partially accounted for by brain volumes and risk factors for cognitive deficits.
CONCLUSIONS
Diabetes is associated with smaller brain volumes in gray but not white matter and increasing ischemic lesion volumes throughout the brain. These markers are associated with but do not fully account for diabetes-related deficits in cognitive function.
doi:10.2337/dc12-0555
PMCID: PMC3526228  PMID: 22933440
16.  Intraindividual Variability in Domain-Specific Cognition and Risk of Mild Cognitive Impairment and Dementia 
Intraindividual variability among cognitive domains may predict dementia independently of interindividual differences in cognition. A multidomain cognitive battery was administered to 2305 older adult women (mean age 74 years) enrolled in an ancillary study of the Women's Health Initiative. Women were evaluated annually for probable dementia and mild cognitive impairment (MCI) for an average of 5.3 years using a standardized protocol. Proportional hazards regression showed that lower baseline domain-specific cognitive scores significantly predicted MCI (N = 74), probable dementia (N = 45), and MCI or probable dementia combined (N = 101) and that verbal and figural memory predicted each outcome independently of all other cognitive domains. The baseline intraindividual standard deviation across test scores (IAV Cognitive Domains) significantly predicted probable dementia and this effect was attenuated by interindividual differences in verbal episodic memory. Slope increases in IAV Cognitive Domains across measurement occasions (IAV Time) explained additional risk for MCI and MCI or probable dementia, beyond that accounted for by interindividual differences in multiple cognitive measures, but risk for probable dementia was attenuated by mean decreases in verbal episodic memory slope. These findings demonstrate that within-person variability across cognitive domains both at baseline and longitudinally independently accounts for risk of cognitive impairment and dementia in support of the predictive utility of within-person variability.
doi:10.1155/2013/495793
PMCID: PMC3881440  PMID: 24454359
17.  Calcium and Vitamin D Supplementation and Cognitive Impairment in the Women’s Health Initiative 
Background
Calcium and vitamin D are thought to play important roles in neuronal functioning. Studies have found associations between low serum vitamin D levels and reduced cognitive functioning, as well as high serum calcium levels and reduced cognitive functioning.
Objectives
To examine the effects of vitamin D and calcium on cognitive outcomes in elderly women.
Design
Post-hoc analysis of a randomized double-blinded placebo-controlled trial.
Setting
40 Women’s Health Initiative clinical centers across the U.S.
Participants
4143 women aged 65 years and older without probable dementia at baseline who participated in the WHI Calcium and Vitamin D trial and the Women’s Health Initiative Memory Study.
Interventions
2034 women were randomized to 1000 mg of calcium carbonate combined with 400 IU of vitamin D3; 2109 women were randomized to placebo.
Measurements
Primary: classifications of probable dementia or mild cognitive impairment via a 4-phase protocol that included central adjudication. Secondary: global cognitive function and individual cognitive subtests.
Results
Mean age of participants was 71 years. During mean follow-up of 7.8 years, there were 39 cases of incident dementia among calcium plus vitamin D subjects compared to 37 cases among placebo subjects (hazard ratio=1.11, 95% CI: 0.71–1.74, p=0.64). Likewise, there were 98 cases of incident mild cognitive impairment among calcium plus vitamin D subjects compared to 108 cases among placebo subjects (hazard ratio=0.95, 95% CI: 0.72–1.25, p=0.72). There were no significant differences in incident dementia or mild cognitive impairment, or in global or domain-specific cognitive function between groups.
Conclusion
There was no association between treatment assignment and incident cognitive impairment. Further studies are needed to investigate the effects of vitamin D and calcium separately, on men and in other age and ethnic groups, and with other doses.
doi:10.1111/jgs.12032
PMCID: PMC3521077  PMID: 23176129
Vitamin D; Calcium; Dementia; Cognition; Mild Cognitive Impairment
18.  Ankle Brachial Index Values, Leg Symptoms, and Functional Performance Among Community‐Dwelling Older Men and Women in the Lifestyle Interventions and Independence for Elders Study 
Background
The prevalence and significance of low normal and abnormal ankle brachial index (ABI) values in a community‐dwelling population of sedentary, older individuals is unknown. We describe the prevalence of categories of definite peripheral artery disease (PAD), borderline ABI, low normal ABI, and no PAD and their association with lower‐extremity functional performance in the LIFE Study population.
Methods and Results
Participants age 70 to 89 in the LIFE Study underwent baseline measurement of the ABI, 400‐m walk, and 4‐m walking velocity. Participants were classified as follows: definite PAD (ABI <0.90), borderline PAD (ABI 0.90 to 0.99), low normal ABI (ABI 1.00 to 1.09), and no PAD (ABI 1.10 to 1.40). Of 1566 participants, 220 (14%) had definite PAD, 250 (16%) had borderline PAD, 509 (33%) had low normal ABI, and 587 (37%) had no PAD. Among those with definite PAD, 65% were asymptomatic. Adjusting for age, sex, race, body mass index, smoking, and comorbidities, lower ABI was associated with longer mean 400‐m walk time: (definite PAD=533 seconds; borderline PAD=514 seconds; low normal ABI=503 seconds; and no PAD=498 seconds [P<0.001]). Among asymptomatic participants with and without PAD, lower ABI values were also associated with longer 400‐m walk time (P<0.001) and slower walking velocity (P=0.042).
Conclusion
Among older community‐dwelling men and women, 14% had PAD and 49% had borderline or low normal ABI values. Lower ABI values were associated with greater functional impairment, suggesting that lower extremity atherosclerosis may be a common preventable cause of functional limitations in older people.
Clinical Trial Registration
URL: http://clinicaltrials.gov/ Unique identifier: NCT01072500.
doi:10.1161/JAHA.113.000257
PMCID: PMC3886743  PMID: 24222666
aging; exercise; peripheral vascular disease
19.  Factors influencing enrollment of African Americans in the Look AHEAD trial 
Clinical trials (London, England)  2011;9(1):10.1177/1740774511427929.
Background
Many factors have been identified that influence the recruitment of African Americans into clinical trials; however, the influence of eligibility criteria may not be widely appreciated. We used the experience from the Look AHEAD (Action for Health in Diabetes) trial screening process to examine the differential impact eligibility criteria had on the enrollment of African Americans compared to other volunteers.
Methods
Look AHEAD is a large randomized clinical trial to examine whether assignment to an intensive lifestyle intervention designed to produce and maintain weight loss reduces the long-term risk of major cardiovascular events in adults with type 2 diabetes. Differences in the screening, eligibility, and enrollment rates between African Americans and members of other racial/ethnic groups were examined to identify possible reasons.
Results
Look AHEAD screened 28,735 individuals for enrollment, including 6226 (21.7%) who were self-identified African Americans. Of these volunteers, 12.9% of the African Americans compared to 19.3% of all other screenees ultimately enrolled (p < 0.001). African Americans no more often than others were lost to follow-up or refused to attend clinic visits to establish eligibility. Furthermore, the enrollment rates of individuals with histories of cardiovascular disease and diabetes therapy did not markedly differ between the ethnic groups. Higher prevalence of adverse levels of blood pressure, heart rate, HbA1c, and serum creatinine among African American screenees accounted for the greater proportions excluded (all p < 0.001).
Conclusions
Compared to non-African Americans, African American were more often ineligible for the Look AHEAD trial due to comorbid conditions. Monitoring trial eligibility criteria for differential impact, and modifying them when appropriate, may ensure greater enrollment yields.
doi:10.1177/1740774511427929
PMCID: PMC3843916  PMID: 22064686
20.  Telephone interview for cognitive status (TICS) screening for clinical trials of physical activity and cognitive training: the seniors health and activity research program pilot (SHARP-P) study† 
International journal of geriatric psychiatry  2011;26(2):10.1002/gps.2503.
Objective:
To examine the performance of the Telephone Interview for Cognitive Status (TICS) for identifying participants appropriate for trials of physical activity and cognitive training interventions.
Methods:
Volunteers (N = 343), ages 70–85 years, who were being recruited for a pilot clinical trial on approaches to prevent cognitive decline, were administered TICS and required to score ≥31 prior to an invitation to attend clinic-based assessments. The frequencies of contraindications for physical activity and cognitive training interventions were tallied for individuals grouped by TICS scores. Relationships between TICS scores and other measures of cognitive function were described by scatterplots and correlation coefficients.
Results:
Eligibility criteria to identify candidates who were appropriate candidates for the trial interventions excluded 51.7% of the volunteers with TICS<31. TICS scores above this range were not strongly related to cognition or attendance at screening visits, however overall enrollment yields were approximately half for participants with TICS = 31 versus TICS = 41, and increased in a graded fashion throughout the range of scores.
Conclusions:
Use of TICS to define eligibility criteria in trials of physical activity and cognitive training interventions may not be worthwhile in that many individuals with low scores would already be eliminated by intervention-specific criteria and the relationship of TICS with clinic-based tests of cognitive function among appropriate candidates for these interventions may be weak. TICS may be most useful in these trials to identify candidates for oversampling in order to obtain a balanced cohort of participants at risk for cognitive decline.
doi:10.1002/gps.2503
PMCID: PMC3832189  PMID: 21229597
clinical trial design; cognitive interventions; eligibility criteria
21.  Alzheimer's Disease Risk Assessment Using Large-Scale Machine Learning Methods 
PLoS ONE  2013;8(11):e77949.
The goal of this work is to introduce new metrics to assess risk of Alzheimer's disease (AD) which we call AD Pattern Similarity (AD-PS) scores. These metrics are the conditional probabilities modeled by large-scale regularized logistic regression. The AD-PS scores derived from structural MRI and cognitive test data were tested across different situations using data from the Alzheimer's Disease Neuroimaging Initiative (ADNI) study. The scores were computed across groups of participants stratified by cognitive status, age and functional status. Cox proportional hazards regression was used to evaluate associations with the distribution of conversion times from mild cognitive impairment to AD. The performances of classifiers developed using data from different types of brain tissue were systematically characterized across cognitive status groups. We also explored the performance of anatomical and cognitive-anatomical composite scores generated by combining the outputs of classifiers developed using different types of data. In addition, we provide the AD-PS scores performance relative to other metrics used in the field including the Spatial Pattern of Abnormalities for Recognition of Early AD (SPARE-AD) index and total hippocampal volume for the variables examined.
doi:10.1371/journal.pone.0077949
PMCID: PMC3826736  PMID: 24250789
22.  Toward a Positive Aging Phenotype for Older Women: Observations From the Women’s Health Initiative 
Background.
To develop a positive aging phenotype, we undertook analyses to describe multiple dimensions of positive aging and their relationships to one another in women 65 years of age and older and evaluate the performance of individual indicators and composite factors of this phenotype as predictors of time to death, years of healthy living, and years of independent living.
Methods.
Data from Women’s Health Initiative clinical trial and observational study participants ages 65 years and older at baseline, including follow-up observations up to 8 years later, were analyzed using descriptive statistics and principal components analysis to identify the factor structure of a positive aging phenotype. The factors were used to predict time to death, years of healthy living (without hospitalization or diagnosis of a serious health condition), and years of independent living (without nursing home admission or use of special services).
Results.
We identified a multidimensional phenotype of positive aging that included two factors: Physical–Social Functioning and Emotional Functioning. Both factors were predictive of each of the outcomes, but Physical–Social Functioning was the strongest predictor. Each standard deviation of increase in Physical–Social Functioning was accompanied by a 23.7% reduction in mortality risk, a 19.4% reduction in risk of major health conditions or hospitalizations, and a 26.3% reduction in risk of dependent living.
Conclusions.
Physical–Social Functioning and Emotional Functioning constitute important components of a positive aging phenotype. Physical–Social Functioning was the strongest predictor of outcomes related to positive aging, including years of healthy living, years of independent living, and time to mortality.
doi:10.1093/gerona/gls117
PMCID: PMC3667695  PMID: 22518819
Positive aging; Phenotypes; Women's health; Healthy life span
23.  Liver fat and SHBG affect insulin resistance in midlife women: The Study of Women’s Health Across the Nation (SWAN) 
Obesity (Silver Spring, Md.)  2013;21(5):1031-1038.
The liver is an insulin-responsive organ that contributes significantly to both whole body insulin sensitivity and availability of sex steroids through the production of sex hormone binding globulin (SHBG). Our objective was to explore whether lower SHBG was associated with ectopic liver fat and mediated its effect on insulin resistance in The Study of Women’s Health Across the Nation (SWAN). A subset of midlife African American and Caucasian women from SWAN (n=208; 50.9±0.18 yrs; 71% Caucasian) had computed tomography scans to quantify visceral, subcutaneous and liver fat. Blood samples were collected and assayed for hormonal and metabolic markers. The cohort, while overweight, was generally healthy, and both liver fat and SHBG were unaffected by menopausal stage or race. Both higher liver fat and lower SHBG levels were significantly associated with higher insulin concentrations after adjustment for adiposity (r=−0.25, p<0.001 and r=−0.18, p=0.01). SHBG and liver fat had additive effects on insulin concentrations such that women with the lowest SHBG and the highest fat levels had the highest values (interaction p=0.09). The association between SHBG and insulin was more apparent among women with fattier livers. SHBG and liver fat appear to have independent effects on insulin levels as adjustment for each other did not diminish the strength of either association (p=0.023 and 0.001 respectively). These results confirmed the strong independent associations between increased liver fat and decreased SHBG with increased metabolic risk in midlife women. Further these data underscore the need for additional research into the role of liver fat in modifying SHBG’s influence on insulin levels.
doi:10.1002/oby.20077
PMCID: PMC3695405  PMID: 23784907
liver fat; sex hormone binding globulin; perimenopause; ectopic fat; insulin resistance
24.  Patterns of Weight Change Associated with Long-Term Weight Change and Cardiovascular Disease Risk Factors in the Look AHEAD Study 
Obesity (Silver Spring, Md.)  2012;20(10):2048-2056.
This paper provides an assessment of the associations that weight loss patterns during the first year of an intensive lifestyle intervention have with four year maintenance and health outcomes. Two components described patterns of weight change during the first year of intervention: one reflected the typical pattern of weight loss over the 12 months, but distinguished those who lost larger amounts across the monthly intervals from those who lost less. The second component reflected the weight change trajectory, and distinguished a pattern of initial weight loss followed by regain versus a more sustained pattern of weight loss 2,438 individuals aged 45–76 years with type 2 diabetes mellitus, who enrolled in the weight loss intervention of a randomized clinical trial, were assigned scores according to how their weight losses reflected these patterns. Relationships these scores had with weight losses and health outcomes (glycosolated hemoglobin – HbA1c; systolic blood pressure, HDL-cholesterol, and triglycerides) over four years were described. Both individuals who had larger month-to-month weight losses in year 1 and whose weight loss was more sustained during the first year had better maintenance of weight loss over four years, independent of characteristics traditionally linked to weight loss success (p<0.001). While relationships with year 4 weight loss were stronger, the pattern of larger monthly weight loss during year 1 was also independently predictive of year 4 levels of HbA1c, HDL-cholesterol, and systolic blood pressure.
doi:10.1038/oby.2012.33
PMCID: PMC3632374  PMID: 22327053
weight loss; type 2 diabetes mellitus; principal components analysis
25.  Validation of a cognitive assessment battery administered by telephone 
Background
While the gold standard method of cognitive assessment is a face-to-face administration, telephone-based assessments offer several advantages if they demonstrate reliability and validity.
Design
Observational study; 110 participants randomly assigned to receive two administrations of the same cognitive test battery 6 months apart in one of four combinations (1st administration/2nd administration): telephone/telephone; telephone/face-to-face; face-to-face/telephone; or face-to-face/face-to-face.
Setting
Academic medical center
Participants
110 non-demented women between the ages of 65 and 90 years.
Measures
The battery included tests of attention, verbal learning and memory, verbal fluency, executive function, working memory and global cognitive functioning plus self-report measures of perceived memory problems, depressive symptoms, sleep disturbance and health-related quality of life. Test-retest reliability, concurrent validity, relative bias associated with telephone administration, and change scores were evaluated.
Results
There were no statistically significant differences in scores on any of the cognitive tests or questionnaires between randomly assigned modes of administration at baseline indicating equivalence across modes. There was no significant bias for tests or questionnaires administered by telephone (ps>0.01). Nor was there a difference in mean change scores between administration modes except for the Category Fluency (p = 0.01) and the California Verbal Learning Test long delay-free recall (p < 0.01). Mean test-retest coefficients for the battery were not significantly different across groups though individual test-retest correlation coefficients were generally higher within mode than across mode.
Conclusions
Telephone administration of cognitive tests and questionnaires to older women is both reliable and valid. Use of telephone batteries can substantially reduce the economic cost and burden of cognitive assessments and increase enrollment, retention and data completeness thereby improving study validity.
doi:10.1111/j.1532-5415.2012.04111.x
PMCID: PMC3448122  PMID: 22985137
cognition; assessment; telephone; validation; tests

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