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1.  Cognitive Function and Brain Structure in Persons With Type 2 Diabetes Mellitus After Intensive Lowering of Blood Pressure and Lipid Levels 
JAMA internal medicine  2014;174(3):324-333.
Persons with type 2 diabetes mellitus (T2DM) are at increased risk for decline in cognitive function, reduced brain volume, and increased white matter lesions in the brain. Poor control of blood pressure (BP) and lipid levels are risk factors for T2DM-related cognitive decline, but the effect of intensive treatment on brain function and structure is unknown.
To examine whether intensive therapy for hypertension and combination therapy with a statin plus a fibrate reduces the risk of decline in cognitive function and total brain volume (TBV) in patients with T2DM.
A North American multicenter clinical trial including 2977 participants without baseline clinical evidence of cognitive impairment or dementia and with hemoglobin A1c (HbA1c) levels less than 7.5% randomized to a systolic BP goal of less than 120 vs less than 140 mm Hg (n = 1439) or to a fibrate vs placebo in patients with low-density lipoprotein cholesterol levels less than 100 mg/dL (n = 1538). Participants were recruited from August 1, 2003, through October 31, 2005, with the final follow-up visit by June 30, 2009.
Cognition was assessed at baseline and 20 and 40 months. A subset of 503 participants underwent baseline and 40-month brain magnetic resonance imaging to assess for change in TBV and other structural measures of brain health.
Baseline mean HbA1c level was 8.3%; mean age, 62 years; and mean duration of T2DM, 10 years. At 40 months, no differences in cognitive function were found in the intensive BP-lowering trial or in the fibrate trial. At 40 months, TBV had declined more in the intensive vs standard BP-lowering group (difference, −4.4 [95% CI, −7.8 to −1.1] cm3; P = .01). Fibrate therapy had no effect on TBV compared with placebo.
In participants with long-standing T2DM and at high risk for cardiovascular events, intensive BP control and fibrate therapy in the presence of controlled low-density lipoprotein cholesterol levels did not produce a measurable effect on cognitive decline at 40 months of follow-up. Intensive BP control was associated with greater decline in TBV at 40 months relative to standard therapy.
TRIAL REGISTRATION Identifier: NCT00000620
PMCID: PMC4423790  PMID: 24493100
2.  Heritability and genetic association analysis of cognition in the Diabetes Heart Study 
Neurobiology of aging  2014;35(8):1958.e3-1958.e12.
Cognitive performance is an important component of healthy aging. Type 2 diabetes (T2D) is associated with negative outcomes for the brain and cognition, although causal mechanisms have not been definitely determined. Genetic risk factors warrant further consideration in this context. This study examined the heritability of cognitive function as assessed by (1) the Digit Symbol Substitution Task; (2) the Modified Mini-Mental State Examination; (3) the Stroop Task; (4) the Rey Auditory-Verbal Learning Task; and (5) the Controlled Oral Word Association Task for Phonemic and Semantic Fluency, in the family-based, T2D-enriched, Diabetes Heart Study sample (n = 550 participants from 257 families). The genetic basis of these cognitive measures was further evaluated by association analysis with candidate single-nucleotide polymorphisms (SNPs) and genome-wide SNP data. Measures of cognitive function were significantly heritable (ĥ2 = 0.28–0.62) following adjustment for age, gender, and education. A total of 31 SNPs (from 26 genes/regions) selected to form an a priori set of candidate SNPs showed limited evidence of association with cognitive function when applying conservative metrics of significance. Genome-wide assessment of both noncoding and coding variants revealed suggestive evidence of association for several coding variants including rs139509083 in CNST (p = 4.9 × 10−9), rs199968569 in PLAA (p = 4.9 × 10−9) and rs138487371 in PCDH8 (p = 3.7 × 10−8). The identification of a heritable component to cognitive performance in T2D suggests a role for genetic contributors to cognitive performance even in the presence of metabolic disease and other associated comorbidities and is supported by the identification of genetic association signals in functionally plausible candidates.
PMCID: PMC4418030  PMID: 24684796
Cognitive function; Heritability; Genetics; Type 2 diabetes
3.  Changes in Cognitive Function in a Randomized Trial of Physical Activity: Results of the Lifestyle Interventions and Independence for Elders Pilot Study 
Cognitive impairment is an important contributor to disability. Limited clinical trial evidence exists regarding the impact of physical exercise on cognitive function (CF). We report results of a pilot study to provide estimates of the relative impact of physical activity (PA) on 1-year changes in cognitive outcomes and to characterize relationships between changes in mobility disability and changes in cognition in older adults at increased risk for disability.
Sedentary persons (102) at increased risk for disability (aged 70–89 years) were randomized to moderate-intensity PA or health education. Participants were administered the Digit Symbol Substitution Test (DSST), Rey Auditory Verbal Learning Test (RAVLT), modified Stroop test, and Modified Mini-Mental State Examination at baseline and 1 year.
Group differences were not significant but improvements in cognitive scores were associated with improvements in physical function. Specifically, the DSST significantly correlated with change in the Short Physical Performance Battery score (r = .38, p = .0002), in chair stand score (r = .26, p = .012), in balance score (r = .21, p = .046), and in 400-m gait speed (r = .15, p = .147). Change recall on the RAVLT and in the Stroop test was also positively correlated with changes in chair stand and balance, respectively.
These results provide further support for the benefits of exercise on CF in older adults. An adequately powered clinical trial of PA involving older adults at increased risk for cognitive disability is needed to expand the indications for prescribing exercise for prevention of decline in brain function.
PMCID: PMC2679423  PMID: 19244157
Exercise; Cognition; Aging; Prevention; LIFE study
4.  Effects of Intensive Diet and Exercise on Knee Joint Loads, Inflammation, and Clinical Outcomes Among Overweight and Obese Adults With Knee Osteoarthritis 
JAMA  2013;310(12):1263-1273.
Knee osteoarthritis (OA), a common cause of chronic pain and disability, has biomechanical and inflammatory origins and is exacerbated by obesity.
To determine whether a ≥10% reduction in body weight induced by diet, with or without exercise, would improve mechanistic and clinical outcomes more than exercise alone.
Single-blind, 18-month, randomized clinical trial at Wake Forest University between July 2006 and April 2011. The diet and exercise interventions were center-based with options for the exercise groups to transition to a home-based program. Participants were 454 overweight and obese older community-dwelling adults (age ≥55 years with body mass index of 27–41) with pain and radiographic knee OA.
Intensive diet-induced weight loss plus exercise, intensive diet-induced weight loss, or exercise.
Mechanistic primary outcomes: knee joint compressive force and plasma IL-6 levels; secondary clinical outcomes: self-reported pain (range, 0–20), function (range, 0–68), mobility, and health-related quality of life (range, 0–100).
At 18 months, 399 participants (88%) completed the study. Compared with exercise participants, knee compressive forces were lower in diet participants and IL-6 levels were lower in diet and diet + exercise participants.
18-mo Outcomes, Mean (95% CI)Exercise(E)Diet (D)D + EDifference,E vs DDifference, Evs D+EWeight loss, kg−1.8(−5.7to1.8)−8.9(−12.4 to −5.3)−10.6(−14.1 to −7.1)Knee compressiveforces, N2687(2590 to 2784)2487(2393 to 2581)2543(2448 to 2637)200(55 to 345)a144(1 to 287)IL-6, pg/mL3.1(2.9 to 3.4)2.7(2.4 to 3.0)2.7(2.5 to 3.0)0.43(0.01 to 0.85)a0.39(−0.03 to 0.81)aPain4.7(4.2 to 5.1)4.8(4.3 to 5.2)3.6(3.2 to 4.1)−0.11(−0.81 to 0.59)1.02(0.33 to 1.71)aFunction18.4(16.9 to 19.9)17.4(15.9 to 18.9)14.1(12.6 to 15.6)0.98(−1.24 to 3.20)4.29(2.07 to 6.50)aSF-36 physical41.9(40.5 to 43.2)42.4(41.1 to 43.7)44.7(43.4 to 46.0)−0.55(−2.53 to 1.43)−2.81(−4.76 to −0.86)aaDifferences were significant.
Among overweight and obese adults with knee OA, after 18 months, participants in the diet + exercise and diet groups had more weight loss and greater reductions in IL-6 levels than those in the exercise group; those in the diet group had greater reductions in knee compressive force than those in the exercise group.
TRIAL REGISTRATION Identifier: NCT00381290
PMCID: PMC4450354  PMID: 24065013
5.  Markers of Cholesterol Transport are Associated with Amyloid Deposition in the Brain 
Neurobiology of aging  2013;35(4):802-807.
Cholesterol is implicated in the development of late onset Alzheimer’s disease (AD). We sought to determine the associations between beta amyloid (Aβ) plaque deposition in vivo using the Pittsburgh Compound B (PiB) and several indices of cholesterol homeostasis (i.e., total cholesterol, HDLc, LDLc, triglycerides, ApoE, clusterin, oxysterol metabolites of cholesterol and previously reported genes associated with late-onset AD) in 175 non-demented elderly subjects. High Aβ deposition was significantly associated with having a lower mini-mental state exams score (<27, p=0.04), high systolic blood pressure (p=0.04), APOE*4 (p<0.01), lower plasma ApoE levels (p=0.02) and variation in the ABCA7 gene (p=0.02) and EPHA1 genes (p=0.02). Cholesterol measures were not related to Aβ deposition in this cohort of non-demented elderly adults. However, plasma and genetic factors relating to cholesterol transport were associated with Aβ deposition in the brain. The better understanding of cholesterol transport mechanisms may lead to the design of potential targets for the prevention of Aβ deposition in the brain.
PMCID: PMC3896052  PMID: 24199960
6.  Effects of Randomization to Intensive Glucose Control on Adverse Events, Cardiovascular Disease, and Mortality in Older Versus Younger Adults in the ACCORD Trial 
Diabetes Care  2014;37(3):634-643.
We explore the effect of randomized treatment, comparing intensive to standard glucose-lowering strategies on major cardiovascular outcomes, death, and severe adverse events in older versus younger participants in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial.
Participants with type 2 diabetes (n = 10,251) with a mean age of 62 years, a median duration of diabetes of 10 years, and a median A1C of 8.1% (65 mmol/mol) were randomized to treatment strategies targeting either A1C <6.0% (42 mmol/mol) or 7.0–7.9% (53–63 mmol/mol) and followed for a mean of 3.7 years. Outcomes were analyzed within subgroups defined by baseline age (<65 vs. ≥65 years).
Older and younger ACCORD participants achieved similar intensive-arm A1C levels and between-arm A1C differences. Within the older subgroup, similar hazards of the cardiovascular primary outcome and total mortality were observed in the two arms. While there was no intervention effect on cardiovascular mortality in the older subgroup, there was an increased risk in the intensive arm for the younger subgroup (older hazard ratio [HR] = 0.97; younger HR = 1.71; P = 0.03). Regardless of intervention arm, the older subgroup experienced higher annualized rates of severe hypoglycemia (4.45% intensive and 1.36% standard) than the younger subgroup (2.45% intensive and 0.80% standard).
Intensive glucose lowering increased the risk of cardiovascular disease and total mortality in younger participants, whereas it had a neutral effect in older participants. The intensive to standard relative risk of severe hypoglycemia was similar in both age subgroups, with higher absolute rates in older participants within both treatment arms.
PMCID: PMC3931381  PMID: 24170759
7.  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.
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.
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.
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.
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 identifier NCT01072500.
PMCID: PMC4266388  PMID: 24866862
International journal of geriatric psychiatry  2013;28(12):10.1002/gps.3949.
Computer-administered assessment of cognitive function is being increasingly incorporated in clinical trials, however its performance in these settings has not been systematically evaluated.
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).
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.
Our results support the use of computer-based tools for assessing cognitive function in multicenter clinical trials of older individuals.
PMCID: PMC3775886  PMID: 23589390
Cognitive function; Clinical trial; Performance measures
9.  Risk of Hospitalized Gastrointestinal Bleeding in Persons Randomized to Diuretic, ACE-Inhibitor, or Calcium-Channel Blocker in ALLHAT 
Calcium channel-blockers (CCB) are an important class of medication useful in the treatment of hypertension. Several observational studies have suggested an association between CCB therapy and gastrointestinal hemorrhage. Using administrative databases, we re-examined in a post-hoc analysis whether the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) participants randomized to the calcium-channel blocker amlodipine had a greater risk of hospitalized gastrointestinal bleeding (a pre-specified outcome) compared to those randomized to the diuretic chlorthalidone or the ACE-inhibitor lisinopril. Participants randomized to chlorthalidone did not have a reduced risk for gastrointestinal bleeding hospitalizations compared to participants randomized to amlodipine (HR, 1.09, 95% CI 0.92-1.28). Those randomized to lisinopril were at increased risk of gastrointestinal bleeding compared those randomized to chlorthalidone (HR, 1.16; 95% CI, 1.00-1.36). In a post-hoc comparison, participants assigned lisinopril therapy had a higher risk of hospitalized gastrointestinal hemorrhage (HR,1.27, 95% CI 1.06-1.51) versus those assigned to amlodipine. In-study use of atenolol prior to first gastrointestinal hemorrhage was related to a lower incidence of GI bleeding (HR, 0.69; 95% CI, 0.57-0.83). In conclusion, hypertensive patients on amlodipine do not have an increased risk of GI bleeding hospitalizations compared to those on either chlorthalidone or lisinopril.
PMCID: PMC3844932  PMID: 24283598
10.  The influence of subclinical cardiovascular disease and related risk factors on cognition in type 2 diabetes mellitus: The DHS-Mind study 
We hypothesized that measures of coronary artery calcified plaque (CAC) collected at baseline from the Diabetes Heart Study (DHS) would explain associations between cognition and diabetes collected at follow-up approximately 7 years later. The DHS is a sibling study of cardiovascular disease (CVD) in a cohort with a high prevalence of type 2 diabetes (~80%). Associations between baseline CAC and cognitive performance were tested using generalized estimating equations and mixed effects models to adjust for familial relationships. Diabetes status was associated (p<0.05) with poorer performance on tests of verbal memory, processing speed, and semantic fluency adjusting for age, sex, education, and hypertension status. As hypothesized, including CAC in the statistical model attenuated this association. Additionally, CAC and fasting glucose predicted performance in tasks not associated with diabetes status in this study (Stroop Task, Phonemic Fluency). These results confirm work attributing the heterogeneity of cognitive outcomes in type 2 diabetes to subclinical risk factors that combine to affect different aspects of brain function. Importantly, these results imply that risk factor intervention should begin before comorbidities, particularly CVD, become clinically apparent.
PMCID: PMC3770734  PMID: 23659774
type 2 diabetes; cardiovascular disease; atherosclerosis; cognition
11.  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.
PMCID: PMC4154884  PMID: 25210447
exercise; physical activity; older adults; dementia
12.  The Demographic and Medical Correlates of Plasma Aβ40 and Aβ42 
Plasma amyloid beta-42 (Aβ42) and Aβ42/Aβ40 are increasingly recognized as biomarkers for dementia, with low levels indicating increased risk. Little is known about the demographic and medical correlates of plasma Aβ40 or Aβ42. In 997 community-dwelling, non-demented older adults from the Health, Aging and Body Composition Study, we determined the cross-sectional association between a wide range of demographic and medical variables with Aβ40 and Aβ42. In multivariate stepwise linear regression models, Aβ40 was significantly associated with race (β=−14.70, F=22.01, p<0.0001), age (β=1.34, F=6.39, p=0.01), creatinine (β=52.91, F=151.77, p<0.0001), and serum brain-derived neurotrophic factor (BDNF) (β=−0.0004, F=7.34, p=0.007); Aβ42 was significantly associated with race (β=−3.72, F=30.83, p<0.0001), sex (β=1.39, F=4.32, p=0.04), education (β=1.50, F=4.78, p=0.03), Apolipoprotein E (APOE) e4 allele status (β=−2.82, F=16.57, p<0.0001), and creatinine (β=9.32, F=120.09, p<0.0001). These correlates should be considered as potential confounders in future studies investigating plasma Aβ as a biomarker of dementia. Understanding fully how these correlates mediate or modify the association between plasma Aβ and dementia will be a fundamental step in determining the biological pathways through which plasma Aβ40 and Aβ42 are associated with dementia, and in determining their full potential as biomarkers.
PMCID: PMC3473156  PMID: 22732677
Plasma amyloid beta; dementia; cognitive decline; biomarker; epidemiology
13.  Low 25-Hydroxyvitamin D Predicts the Onset of Mobility Limitation and Disability in Community-Dwelling Older Adults: The Health ABC Study 
Although low 25-hydroxyvitamin D (25(OH)D) is prevalent among older adults and is associated with poor physical function, longitudinal studies examining vitamin D status and physical function are lacking. We examined the association between 25(OH)D, parathyroid hormone (PTH), and the onset of mobility limitation and disability over 6 years of follow-up in community-dwelling, initially well-functioning older adults participating in the Health, Aging and Body Composition study (n = 2,099).
Serum 25(OH)D and PTH were measured at the 12-month follow-up visit (1998–1999). Mobility limitation and disability (any/severe difficulty walking 1/4 mile or climbing 10 steps) was assessed semiannually over 6 years of follow-up. The association between 25(OH)D, PTH, and mobility limitation and disability was examined using Cox proportional hazard regression models adjusted for demographics, season, behavioral characteristics, and chronic conditions.
At baseline, 28.9% of the participants had 25(OH)D <50 nmol/L and 36.1% had 25(OH)D of 50 to <75 nmol/L. Participants with 25(OH)D <50 and 50 to <75 nmol/L were at greater risk of developing mobility limitation (HR (95% CI): 1.29 (1.04–1.61) and 1.27 (1.05–1.53), respectively) and mobility disability (HR (95% CI): 1.93 (1.32–2.81) and 1.30 (0.92–1.83), respectively) over 6 years of follow-up compared with participants with 25(OH)D ≥75 nmol/L. Elevated PTH, however, was not significantly associated with developing mobility limitation or disability.
Low 25(OH)D was associated with an increased risk of mobility limitation and disability in community-dwelling, initially well-functioning black and white older adults. Prevention or treatment of low 25(OH)D may provide a pathway for reducing the burden of mobility disability in older adults.
PMCID: PMC3598356  PMID: 22573914
25-hydroxyvitamin D; Mobility limitation; Vitamin D; Parathyroid hormone
14.  25-Hydroxyvitamin D Status and Change in Physical Performance and Strength in Older Adults 
American Journal of Epidemiology  2012;176(11):1025-1034.
Low 25-hydroxyvitamin D (25(OH)D) concentrations are common among older adults and are associated with poorer physical performance and strength, but results from longitudinal studies have been inconsistent. The 25(OH)D threshold for physical performance and strength was determined, and both cross-sectional and longitudinal associations between 25(OH)D and physical performance and strength were examined, in men and women aged 71–80 years from the Health, Aging, and Body Composition Study (n = 2,641). Baseline serum 25(OH)D was measured in 1998–1999, and physical performance and strength were measured at baseline and at 2- and 4-year follow-up. Piecewise regression models were used to determine 25(OH)D thresholds. Linear regression and mixed models were used to examine cross-sectional and longitudinal associations. The 25(OH)D thresholds were 70–80 nmol/L for physical performance and 55–70 nmol/L for strength. Participants with 25(OH)D <50 nmol/L had poorer physical performance at baseline and at 2- and 4-year follow-up than participants with 25(OH)D ≥75 nmol/L (P < 0.01). Although physical performance and strength declined over 4 years of follow-up (P < 0.0001), in general, the rate of decline was not associated with baseline 25(OH)D. Older adults with low 25(OH)D concentrations had poorer physical performance over 4 years of follow-up, but low 25(OH)D concentrations were not associated with a faster rate of decline in physical performance or strength.
PMCID: PMC3571245  PMID: 23118104
aged; 25-hydroxyvitamin D; muscle strength; physical performance
15.  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.
PMCID: PMC3826736  PMID: 24250789
16.  The Feasibility of Inpatient Geriatric Assessment for Older Adults Receiving Induction Chemotherapy for Acute Myelogenous Leukemia 
To test the feasibility and utility of a bedside geriatric assessment (GA) to detect impairment in multiple geriatric domains in older adults initiating chemotherapy for acute myelogenous leukemia (AML).
Prospective observational cohort study.
Single academic institution.
Individuals aged 60 and older with newly diagnosed AML and planned chemotherapy.
Bedside GA was performed during inpatient exmination for AML. GA measures included the modified Mini-Mental State Examination; Center for Epidemiologic Studies Depression Scale; Distress Thermometer, Pepper Assessment Tool for Disability (includes self- reported activities of daily living (ADLs), instrumental ADLs, and mobility questions); Short Physical Performance Battery (includes timed 4-m walk, chair stands, standing balance); grip strength, and Hematopoietic Cell Transplantation Comorbidity Index.
Of 54 participants (mean age 70.8 ± 6.4) eligible for this analysis, 92.6% completed the entire GA battery (mean time 44.0 ± 14 minutes). The following impairments were detected: cognitive impairment, 31.5%; depression, 38.9%; distress, 53.7%; impairment in ADLs, 48.2%; impaired physical performance, 53.7%; and comorbidity, 46.3%. Most were impaired in one (92.6%) or more (63%) functional domains. For the 38 participants rated as having good performance status according to standard oncologic assessment (Eastern Cooperative Oncology Performance Scale score ≤1), impairments in individual GA measures ranged from 23.7% to 50%. Significant variability in cognitive, emotional, and physical status was detected even after stratification according to tumor biology (cytogenetic risk group classification).
Inpatient GA was feasible and added new information to standard oncology assessment, which may be important for stratifying therapeutic risk in older adults with AML.
PMCID: PMC3782375  PMID: 22091497
geriatric assessment; acute myelogenous leukemia; cancer; functional status; elderly
17.  A Randomized Controlled Trial of Telephone-Delivered Cognitive-Behavioral Therapy for Late-life Anxiety Disorders 
Older adults face a number of barriers to receiving psychotherapy, such as a lack of transportation and access to providers. One way to overcome such barriers is to provide treatment by telephone. The purpose of this study was to examine the effects of cognitive behavioral therapy delivered by telephone (CBT-T) to older adults diagnosed with an anxiety disorder.
Randomized controlled trial.
Participants' homes.
Sixty participants ≥ 60 years of age with a diagnosis of Generalized Anxiety Disorder, Panic Disorder, or Anxiety Disorder Not Otherwise Specified.
CBT-T vs. information-only comparison.
Co-primary outcomes included worry (Penn State Worry Questionnaire) and general anxiety (State Trait Anxiety Inventory). Secondary outcomes included clinician-rated anxiety (Hamilton Anxiety Rating Scale), anxiety sensitivity (Anxiety Sensitivity Index), depressive symptoms (Beck Depression Inventory), quality of life (SF-36), and sleep (Insomnia Severity Index). Assessments were completed prior to randomization, immediately upon completion of treatment, and 6 months after completing treatment.
CBT-T was superior to information-only in reducing general anxiety (ES = 0.71), worry (ES = 0.61), anxiety sensitivity (ES = 0.85), and insomnia (ES = 0.82) at the post-treatment assessment; however, only the reductions in worry were maintained by the 6 month follow-up assessment (ES = 0.80).
These results suggest that CBT-T may be efficacious in reducing anxiety and worry in older adults, but additional sessions may be needed to maintain these effects.
PMCID: PMC3407971  PMID: 22828172
anxiety; cognitive-behavioral therapy; elderly; Generalized Anxiety Disorder; Panic Disorder; telephone-delivered psychotherapy
18.  Strength Training for Arthritis Trial (START): design and rationale 
Muscle loss and fat gain contribute to the disability, pain, and morbidity associated with knee osteoarthritis (OA), and thigh muscle weakness is an independent and modifiable risk factor for it. However, while all published treatment guidelines recommend muscle strengthening exercise to combat loss of muscle mass and strength in knee OA patients, previous strength training studies either used intensities or loads below recommended levels for healthy adults or were generally short, lasting only 6 to 24 weeks. The efficacy of high-intensity strength training in improving OA symptoms, slowing progression, and affecting the underlying mechanisms has not been examined due to the unsubstantiated belief that it might exacerbate symptoms. We hypothesize that in addition to short-term clinical benefits, combining greater duration with high-intensity strength training will alter thigh composition sufficiently to attain long-term reductions in knee-joint forces, lower pain levels, decrease inflammatory cytokines, and slow OA progression.
This is an assessor-blind, randomized controlled trial. The study population consists of 372 older (age ≥ 55 yrs) ambulatory, community-dwelling persons with: (1) mild-to-moderate medial tibiofemoral OA (Kellgren-Lawrence (KL) = 2 or 3); (2) knee neutral or varus aligned knee ( -2° valgus ≤ angle ≤ 10° varus); (3) 20 kg.m-2 ≥ BMI ≤ 45 kg.m-2; and (3) no participation in a formal strength-training program for more than 30 minutes per week within the past 6 months. Participants are randomized to one of 3 groups: high-intensity strength training (75-90% 1Repetition Maximum (1RM)); low-intensity strength training (30-40%1RM); or healthy living education. The primary clinical aim is to compare the interventions’ effects on knee pain, and the primary mechanistic aim is to compare their effects on knee-joint compressive forces during walking, a mechanism that affects the OA disease pathway. Secondary aims will compare the interventions’ effects on additional clinical measures of disease severity (e.g., function, mobility); disease progression measured by x-ray; thigh muscle and fat volume, measured by computed tomography (CT); components of thigh muscle function, including hip abductor strength and quadriceps strength, and power; additional measures of knee-joint loading; inflammatory and OA biomarkers; and health-related quality of life.
Test-retest reliability for the thigh CT scan was: total thigh volume, intra-class correlation coefficients (ICC) = 0.99; total fat volume, ICC = 0.99, and total muscle volume, ICC = 0.99. ICC for both isokinetic concentric knee flexion and extension strength was 0.93, and for hip-abductor concentric strength was 0.99. The reliability of our 1RM testing was: leg press, ICC = 0.95; leg curl, ICC = 0.99; and leg extension, ICC = 0.98. Results of this trial will provide critically needed guidance for clinicians in a variety of health professions who prescribe and oversee treatment and prevention of OA-related complications. Given the prevalence and impact of OA and the widespread availability of this intervention, assessing the efficacy of optimal strength training has the potential for immediate and vital clinical impact.
Trial registration, NCT01489462
PMCID: PMC3722013  PMID: 23855596
19.  Poor Cognitive Function and Risk of Severe Hypoglycemia in Type 2 Diabetes 
Diabetes Care  2012;35(4):787-793.
Self-management of type 2 diabetes including avoidance of hypoglycemia is complex, but the impact of cognition on safe self-management is not well understood. This study aimed to assess the effect of baseline cognitive function and cognitive decline on subsequent risk of severe hypoglycemia and to assess the effect of different glycemic strategies on these relationships.
Prospective cohort analysis of data from the ACCORD trial included 2,956 adults aged ≥55 years with type 2 diabetes and additional cardiovascular risk factors. Cognitive tests (Digit Symbol Substitution Test [DSST], Rey Auditory Verbal Learning Test, Stroop Test, and Mini Mental Status Examination) were conducted at baseline and 20 months. Study outcomes were incident confirmed severe hypoglycemia requiring medical assistance (HMA) and hypoglycemia requiring any assistance (HAA).
After a median 3.25-year follow-up, a 5-point-poorer baseline score on the DSST was predictive of a first episode of HMA (hazard ratio 1.13 [95% CI 1.08–1.18]). Analyses of the other cognitive tests and of HAA were consistent with the DSST results. Cognitive decline over 20 months increased the risk of subsequent hypoglycemia to a greater extent in those with lower baseline cognitive function (Pinteraction = 0.037). Randomization to an intensive versus standard glycemic strategy had no impact on the relationship between cognitive function and the risk of severe hypoglycemia.
Poor cognitive function increases the risk of severe hypoglycemia in patients with type 2 diabetes. Clinicians should consider cognitive function in assessing and guiding their patients regarding safe diabetes self-management regardless of their glycemic targets.
PMCID: PMC3308284  PMID: 22374637
20.  Effects of randomization to intensive glucose lowering on brain structure and function in type 2 diabetes ACCORD Memory in Diabetes Study 
Lancet Neurology  2011;10(11):969-977.
Persons with type 2 diabetes (T2D) are at risk for cognitive impairment and brain atrophy. The ACCORD Memory in Diabetes (MIND) Study investigated whether persons randomized to an intensive glycaemic therapeutic strategy targeting HbA1c to <6% had better cognitive function and a larger brain volume at 40 months than persons randomized to a standard strategy targeting HbA1c to 7%–7.9%.
ACCORD MIND was a double 2×2 factorial parallel group randomised trial conducted in 52 clinical sites in North America. Participants [age 55 – <80 years] with T2D, high HbA1c concentrations (>7.5%), and at high risk for cardiovascular events were randomised to treatment groups using a centralized web-based system. Clinic staff and participants were not blinded to treatment arm. The cognitive primary outcome, the Digit Symbol Substitution Test (DSST) score, was assessed at baseline, 20 and 40 months. Total brain volume (TBV), the primary brain structure outcome, was assessed with MRI at baseline and 40 months in a sub-set of 632 participants. All participants with follow-up data were included in the primary analyses. In February, 2008, increased mortality risk led to the termination of the intensive therapy and transition of those participants to standard glycaemic treatment.
Randomised patients (n=2977; mean age 62.3 years) were consecutively enrolled; the final analysis included 1358 intensive and 1416 standard arm participants with a 20 or 40 month DSST score. Of the 614 with a baseline MRI, 230 intensive and 273 standard therapy participants were included in the analysis. There was no treatment difference in the DSST score. The intensive group had a greater TBV than the standard group (difference, 4.62; 95% CI 2.0 to7.3 cm3; p=0.0007).
Although significant differences in TBV favored the intensive therapy, cognitive outcomes were not different. Combined with the unfavorable effects on other ACCORD outcomes, MIND findings do not support using intensive therapy to reduce the adverse effects of diabetes on the brain in patients similar to MIND participants. ( number, NCT00182910).
PMCID: PMC3333485  PMID: 21958949
21.  Subclinical Vascular Disease Burden and Risk for Death and Cardiovascular Events in Older Community Dwellers 
Individual measures and previous composite measures of subclinical vascular disease defined high risk for cardiovascular events, but did not detect low and modest risk. A different approach might better describe the spectrum from low to high risk.
Methods and Results.
In the Cardiovascular Health Study, 3,252 participants without history of clinical cardiovascular disease (M ± SD 74.3 years ± 5.1, 63% women, 17% African Americans) had noninvasive vascular assessments in 1992–1993. We assigned a score of 0, 1, or 2 (no, mild, or severe abnormalities) to ankle–arm index, electrocardiogram, and common carotid intima-media thickness, based on clinical cutoffs. A summary index (range 0–6, absent to severe disease) summed individual scores. Abdominal aortic ultrasound and brain magnetic resonance imaging were collected in a subsample. Mortality and incident cardiovascular events were identified through June 2008. Event and death rates increased across index grades. Comparing grades 1 to 5+ with absent disease, and adjusting for demographics, hazard ratios for cardiovascular events within 8 years ranged from 1.1 (95% confidence interval 0.8–1.6) to 4.7 (3.4–6.9) and, for mortality, from 1.5 (1.0–2.3) to 5.0 (3.3–7.7) (p for trend across grades <.001 for both outcomes). Adjustment for cardiovascular risk factors did not substantially change the associations. The index improved mortality risk classification over demographics and risk factors in participants who did not die during the follow-up. Including in the index the aortic ultrasound and the brain magnetic resonance imaging further improved risk classification.
Older adults with minimal subclinical vascular disease had low cardiovascular events risk and mortality. This approach might more fully account for vascular burden.
PMCID: PMC3202905  PMID: 21705627
Epidemiology; Aging; Atherosclerosis; Cardiovascular disease; Mortality
22.  Biomarkers of Renal Function and Cognitive Impairment in Patients With Diabetes 
Diabetes Care  2011;34(8):1827-1832.
Kidney disease is associated with cognitive impairment in studies of nondiabetic adults. We examined the cross-sectional relation between three measures of renal function and performance on four measures of cognitive function in the Action to Control Cardiovascular Risk in Diabetes Memory in Diabetes (ACCORD-MIND) study.
The relationships among estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 (n = 2,968), albumin/creatinine ratio (ACR) ≥30 μg/mg (n = 2,957), and cystatin C level >1.0 mg/L (n = 532) with tertile of performance on the Mini-Mental State Examination, Rey Auditory Verbal Learning Test (RAVLT), Digit Symbol Substitution Test (DSST), and Stroop Test of executive function were measured.
In adjusted logistic regression models, ACR ≥30 μg/mg was associated with performance in the lowest tertile, compared with the highest two tertiles, on the RAVLT (odds ratio 1.30, 95% CI 1.09–1.56, P = 0.006), equivalent to 3.6 years of aging, and on the DSST (1.47, 1.20–1.80, P = 0.001), equivalent to 3.7 years of aging. Cystatin C >1.0 mg/L was borderline associated with the lowest tertile on the DSST (1.81, 0.93–3.55, P = 0.08) and Stroop (1.78, 0.97–3.23, P = 0.06) in adjusted models. eGFR was not associated with any measure of cognitive performance.
In diabetic people with HbA1c >7.5% at high risk for cardiovascular disease, decreased cognitive function was associated with kidney disease as measured by ACR, a measure of microvascular endothelial pathology, and cystatin C, a marker of eGFR.
PMCID: PMC3142061  PMID: 21715519
23.  The Lifestyle Interventions and Independence for Elders Study: Design and Methods 
As the number of older adults in the United States rises, maintaining functional independence among older Americans has emerged as a major clinical and public health priority. Older people who lose mobility are less likely to remain in the community; demonstrate higher rates of morbidity, mortality, and hospitalizations; and experience a poorer quality of life. Several studies have shown that regular physical activity improves functional limitations and intermediate functional outcomes, but definitive evidence showing that major mobility disability can be prevented is lacking. A Phase 3 randomized controlled trial is needed to fill this evidence gap.
The Lifestyle Interventions and Independence for Elders (LIFE) Study is a Phase 3 multicenter randomized controlled trial designed to compare a supervised moderate-intensity physical activity program with a successful aging health education program in 1,600 sedentary older persons followed for an average of 2.7 years.
LIFE's primary outcome is major mobility disability, defined as the inability to walk 400 m. Secondary outcomes include cognitive function, serious fall injuries, persistent mobility disability, the combined outcome of major mobility disability or death, disability in activities of daily living, and cost-effectiveness.
Results of this study are expected to have important public health implications for the large and growing population of older sedentary men and women.
PMCID: PMC3193523  PMID: 21825283
Disability; Physical activity; Exercise; Geriatrics; Physical function
24.  The Relationship Between Cognitive Function and Physical Performance in Older Women: Results From the Women’s Health Initiative Memory Study 
Cognitive function and physical performance are associated, but the common sequence of cognitive and physical decline remains unclear.
In the Women’s Health Initiative Memory Study (WHIMS) clinical trial, we examined associations at baseline and over a 6-year follow-up period between the Modified Mini-Mental State (3MS) Examination and three physical performance measures (PPMs): gait speed (meters/second), chair stands (number of stands in 15 seconds), and grip strength (kilograms). Using mixed models, we examined the baseline 3MS as predictor of change in PPM, change in the 3MS as predictor of change in PPM, and baseline PPM as predictors of 3MS change.
Among 1,793 women (mean age = 70.3 years, 89% white, and mean 3MS score = 95.1), PPM were weakly correlated with 3MS—gait speed: r = .06, p = .02; chair stands: r = .09, p < .001; and grip strength: r = .10, p < .001. Baseline 3MS score was associated with subsequent PPM decline after adjustment for demographics, comorbid conditions, medications, and lifestyle factors. For every SD (4.2 points) higher 3MS score, 0.04 SD (0.04 m/s) less gait speed and 0.05 SD (0.29 kg) less grip strength decline is expected over 6 years (p ≤ .01 both). Changes in 3MS and PPM were associated, particularly with chair stands and grip strength (p < .003 both). Baseline PPMs were not associated with subsequent 3MS change.
Baseline global cognitive function and change in global cognitive function were associated with physical performance change, but baseline physical performance was not associated with cognitive change in this cohort. These analyses support the hypothesis that cognitive decline on average precedes or co-occurs with physical performance decline.
PMCID: PMC2822281  PMID: 19789197
Cognitive function; Physical performance; Cognition; Physical function
25.  Feasibility and Acceptability of Bibliotherapy and Telephone Sessions for the Treatment of Late-life Anxiety Disorders 
Clinical gerontologist  2010;33(1):62-68.
This article describes the development of Biblio and Telephone Therapy or BTT, a cognitive-behavioral treatment program for late-life anxiety disorders. Although studies have examined bibliotherapy for the treatment of late-life depression, none have studied it as a format for treating late-life anxiety. The application of this treatment to 4 older adults with Generalized Anxiety Disorder (GAD) and/or Panic Disorder (PD) is described and benefits, advantages and limitations are discussed.
PMCID: PMC2909126  PMID: 20661315

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