Restricted physical activity commonly occurs following acute musculoskeletal pain in older adults and may influence long-term outcomes. We sought to examine the relationship between restricted physical activity after motor vehicle collision (MVC) and the development of persistent pain.
We examined data from a prospective study of adults ≥65 years of age presenting to the emergency department (ED) after MVC without life-threatening injuries. Restricted physical activity 6 weeks after MVC was defined in three different ways: 1) by a ≥25 point decrease in Physical Activity Scale in the Elderly (PASE) score, 2) by the answer “yes” to the question, “during the past two weeks, have you stayed in bed for at least half a day?”, and 3) by the answer “yes” to the question, “during the past two weeks, have you cut down on your usual activities as compared to before the accident?” We examined relationships between each definition of restricted activity and pain severity, pain interference, and functional capacity at 6 months with adjustment for confounders.
Within the study sample (N = 164), adjusted average pain severity scores at 6 months did not differ between patients with and without restricted physical activity based on decreased PASE score (2.54 vs. 2.07, p = 0.32). In contrast, clinically and statistically important differences in adjusted average pain severity at 6 months were observed for patients who reported spending half a day in bed vs. those who did not (3.56 vs. 1.91, p < 0.01). In adjusted analyses, both decreased PASE score and cutting down on activity were associated with functional capacity at 6 months, but only decreased PASE score was associated with increased ADL difficulty at 6 months (0.70 vs. -0.01, p = 0.02).
Among older adults experiencing MVC, those reporting bed rest or reduced activity 6 weeks after the collision reported higher pain and pain interference scores at 6 months. More research is needed to determine if interventions to promote activity can improve outcomes after MVC in older adults.
Aged; Motor Activity; Emergency medicine; Pain; Geriatrics; Traffic accidents
Understanding the mechanisms that contribute to walking speed decline can provide needed insight for developing targeted interventions to reduce the rate and likelihood of decline.
Examine the association between gait characteristics and walking speed decline in older adults.
Participants in the Baltimore Longitudinal Study of Aging aged 60 to 89 were evaluated in the gait laboratory which used a three dimensional motion capture system and force platforms to assess cadence, stride length, stride width, percent of gait cycle in double stance, anterior-posterior mechanical work expenditure (MWE), and medial-lateral MWE. Usual walking speed was assessed over 6 meters at baseline and follow-up. Gait characteristics associated with meaningful decline (decline ≥ 0.05 m/s/y) in walking speed were evaluated by logistic regression adjusted for age, sex, race, height, weight, initial walking speed and follow-up time.
Among 362 participants, the average age was 72.4 (SD=8.1) years, 51% were female, 27% were black and 23% were identified has having meaningful decline in usual walking speed with an average follow-up time of 3.2 (1.1) years. In the fully adjusted model, faster cadence [ORadj=0.65 95% CI (0.43,0.97)] and longer strides [ORadj=0.87 95% CI (0.83,0.91)] were associated with lower odds of decline. However age [ORadj=1.04 95% CI (0.99,1.10)] was not associated with decline when controlling for gait characteristics and other demographics.
A sizable proportion of healthy older adults experienced walking speed decline over an average of 3 years. Longer stride and faster cadence were protective against meaningful decline in usual walking speed.
Results from numerous studies suggest protective effects of the Mediterranean diet for cardiovascular disease, cancer, and mortality. Evidence for an association with a decreased risk of cognitive decline is less consistent and studies are limited by a lack of diversity in their populations.
We followed 2,326 older adults (38.2% black, 51.3% female, aged 70–79 at baseline) over 8 years in a prospective cohort study in the United States (Health, Aging and Body Composition study). To measure adherence to a Mediterranean diet, we calculated race-specific tertiles of the MedDiet score (range: 0–55) using baseline food frequency questionnaires. Cognitive decline was assessed using repeated Modified Mini Mental State Examination scores over the study. We used linear mixed models to assess the association between MedDiet score and trajectory of cognitive decline.
Among blacks, participants with high MedDiet scores had a significantly lower mean rate of decline on the Modified Mini Mental State Examination score compared with participants with lower MedDiet scores (middle and bottom tertiles). The mean difference in points per year was 0.22 (95% confidence interval: 0.05–0.39; p = .01) after adjustment for age, sex, education, body mass index, current smoking, physical activity, depression, diabetes, total energy intake, and socioeconomic status. No association between MedDiet scores and change in Modified Mini Mental State Examination score was seen among white participants (p = .14).
Stronger adherence to the Mediterranean diet may reduce the rate of cognitive decline among black, but not white older adults. Further studies in diverse populations are needed to confirm this association and pinpoint mechanisms that may explain these results.
Epidemiology; Nutrition; Cognitive aging; Alzheimers; Cognition.
A brief, inexpensive screening test for sarcopenia would be helpful for clinicians and their patients. To screen for persons with sarcopenia, we developed a simple five‐item questionnaire (SARC‐F) based on cardinal features or consequences of sarcopenia.
We investigated the utility of SARC‐F in the African American Health (AAH) study, Baltimore Longitudinal Study of Aging (BLSA), and National Health and Nutrition Examination Survey (NHANES). Internal consistency reliability for SARC‐F was determined using Cronbach's alpha. We evaluated SARC‐F factorial validity using principal components analysis and criterion validity by examining its association with exam‐based indicators of sarcopenia. Construct validity was examined using cross‐sectional and longitudinal differences among those with high (≥4) vs. low (<4) SARC‐F scores for mortality and health outcomes.
SARC‐F exhibited good internal consistency reliability and factorial, criterion, and construct validity. AAH participants with SARC‐F scores ≥ 4 had more Instrumental Activity of Daily Living (IADL) deficits, slower chair stand times, lower grip strength, lower short physical performance battery scores, and a higher likelihood of recent hospitalization and of having a gait speed of <0.8 m/s. SARC‐F scores ≥ 4 in AAH also were associated with 6 year IADL deficits, slower chair stand times, lower short physical performance battery scores, having a gait speed of <0.8 m/s, being hospitalized recently, and mortality. SARC‐F scores ≥ 4 in the BLSA cohort were associated with having more IADL deficits and lower grip strength (both hands) in cross‐sectional comparisons and with IADL deficits, lower grip strength (both hands), and mortality at follow‐up. NHANES participants with SARC‐F scores ≥ 4 had slower 20 ft walk times, had lower peak force knee extensor strength, and were more likely to have been hospitalized recently in cross‐sectional analyses.
The SARC‐F proved internally consistent and valid for detecting persons at risk for adverse outcomes from sarcopenia in AAH, BLSA, and NHANES.
Sarcopenia; Screening; Mobility; Function
Whether ApolipoproteinE (APOE) E4 allele status which is associated with an increased risk of cognitive decline is also associated with hearing impairment is unknown.
We studied 1833 men and women enrolled in the Health, Aging and Body Composition study. Regression models adjusted for demographic and cardiovascular risk factors were used to assess the cross-sectional association of APOE-E4 status with individual pure tone hearing thresholds and the 4-frequency pure tone average (0.5 kHz–4kHz) in the better hearing ear.
Compared to participants with no APOE-E4 alleles, participants with one allele had better thresholds at 4.0kHz (β= −2.72dB, p = 0.013) and 8.0 kHz (β= −3.05kHz, p = 0.006), and participants with two alleles had better hearing thresholds at 1.0kHz (β= −8.56dB, p=0.021).
Our results suggest that APOE-E4 allele status may be marginally associated with better hearing thresholds in older adults.
Apolipoprotein E; hearing thresholds; hearing loss; cognition; aging; dementia
With aging, customary gait patterns change and energetic efficiency declines, but the relationship between these alterations is not well understood. If gait characteristics that develop with aging explain part of the decline in energetic efficiency that occur in most aging individuals, then efforts to modify these characteristics could delay or prevent mobility limitation. This study characterizes gait patterns in older persons with and without knee pain and tests the hypothesis that changes in gait characteristics due to knee pain are associated with increased energetic cost of walking in older adults. Study participants were 364 men and 170 women aged 60 to 96 years enrolled in the Baltimore Longitudinal Study of Aging (BLSA), of whom 86 had prevalent knee pain. Gait patterns were assessed at participant self-selected usual pace in the gait laboratory, and the energetic cost of walking was assessed by indirect calorimetry during self-selected usual pace walking over 2.5 min in a tiled corridor using a portable equipment. Participants with knee pain were less energetically efficient than those without pain (oxygen consumption 0.97 vs. 0.88 ml/(10 m · 100 kg); p = 0.002) and had slower gait speed and smaller range of motion (ROM) at the hip and knee joints (p < 0.05, for all). Slower gait speed and lower knee ROM in participants with knee pain and longer double support time and higher ankle ROM in participants without knee pain were associated with lower energetic efficiency (p < 0.05, for all). Slower gait speed and lower knee ROM were correlates of knee pain and were found to mediate the association between age and oxygen consumption. Although knee pain is associated with a higher energetic cost of walking, gait characteristics associated with energetic efficiency differ by pain status which suggests that compensatory strategies both in the presence and absence of pain may impact gait efficiency.
Oxygen consumption; Knee pain; Energy efficiency in gait; Compensatory effort
Lower rates of cancer in the oldest old and in nursing home populations may reflect the increasing prevalence of frailty and a diminished capacity to sustain cancer cell growth and proliferation. This study aimed to determine cancer incidence in the frail relative to non-frail community resident older adults.
MATERIALS AND METHODS
Data come from 3,969 participants free of diagnosed cancer at the sixth follow up from three sites of the Established Populations for Epidemiologic Studies of the Elderly (EPESE), a population-based cohort study. Frailty status was determined from physical performance testing and self reported dependency in activities of daily living. Cancer incidence over the four subsequent years was identified through linkage with Medicare claims data. Logistic regression was used to estimate the odds of cancer incidence with respect to frailty status in multiple models with progressive adjustment for covariates.
Of the 3,969 participants, 1,340 (33·8%) were identified as frail. Cancer incidence at 4 years was lower in frail participants overall (OR 0·64; 95% CI 0·46–0·89) and frail men in particular (OR 0·54; 95% CI 0·33–0·87). Incidence was lower in women (3.7%) than men (8.8%), but was not lower in frail women compared with non-frail women (OR 0·77; 95% CI 0·48 –1·23).
Frailty status was associated with decreased cancer incidence, particularly in men, and suggests that mechanisms related to the pathogenesis of frailty may also play a role in inhibiting tumorigenesis. Why this would be more apparent in men than women remains to be clarified.
frailty; cancer; incidence; cellular senescence; microenvironment; elderly
Hearing impairment (HI) is highly prevalent in older adults and is associated with social isolation, depression, and risk of dementia. Whether HI is associated with broader downstream outcomes is unclear. We undertook this study to determine whether audiometric HI is associated with mortality in older adults.
Prospective observational data from 1,958 adults ≥70 years of age from the Health, Aging, and Body Composition Study were analyzed using Cox proportional hazards regression. Participants were followed for 8 years after audiometric examination. Mortality was adjudicated by obtaining death certificates. Hearing was defined as the pure-tone average of hearing thresholds in decibels re: hearing level (dB HL) at frequencies from 0.5 to 4kHz. HI was defined as pure-tone average >25 dB HL in the better ear.
Of the 1,146 participants with HI, 492 (42.9%) died compared with 255 (31.4%) of the 812 with normal hearing (odds ratio = 1.64, 95% CI: 1.36–1.98). After adjustment for demographics and cardiovascular risk factors, HI was associated with a 20% increased mortality risk compared with normal hearing (hazard ratio = 1.20, 95% CI: 1.03–1.41). Confirmatory analyses treating HI as a continuous predictor yielded similar results, demonstrating a nonlinear increase in mortality risk with increasing HI (hazard ratio = 1.14, 95% CI: 1.00–1.29 per 10 dB of threshold elevation up to 35 dB HL).
HI in older adults is associated with increased mortality, independent of demographics and cardiovascular risk factors. Further research is necessary to understand the basis of this association and whether these pathways might be amenable to hearing rehabilitation.
Epidemiology; Longevity; Outcomes; Public health; Successful aging.
Multimorbidity increases with aging, but risk factors beyond age are unknown.
To investigate the association of inflammatory and anabolic hormonal biomarkers with presence and prospective development of multimorbidity.
Nine-year longitudinal study of 1018 participants aged 60 years or older (InCHIANTI Study). Multimorbidity was evaluated at baseline and follow-up visits as number of diagnosed diseases from a predefined list of 15 candidate chronic conditions, defined according to standard clinical criteria. Linear mixed models were used to test cross-sectional and longitudinal associations between candidate biomarkers and multimorbidity.
At baseline, multimorbidity was significantly higher in older participants (p < .001) and higher IL-6, IL-1ra, TNF-α receptor II (TNFAR2), and lower dehydroepiandrosterone sulfate were associated with higher number of diseases, independent of age, sex, body mass index, and education. The rate of longitudinal increase in number of chronic diseases was significantly steeper in participants who were older at baseline (p < .001). In addition, higher baseline IL-6 and steeper increase of IL-6 levels were significantly and independently associated with a steeper increase in multimorbidity over time (p < .001 and p = .003, respectively). Sensitivity analyses, performed using 15 different models obtained by removing each of 15 conditions included in the original list of candidate diseases, confirmed that results were not driven by any specific condition.
Accumulation of chronic diseases accelerates at older ages and in persons with higher baseline levels and steeper increase over time of IL-6. High IL-6 and increase in IL-6 may serve as early warning sign to better target interventions aimed at reducing the burden of multimorbidity.
Multimorbidity; Inflammation; Interleukin-6; Aging; Chronic diseases.
To examine the association between multiple measures of visual impairment and incident mobility limitations in older adults.
Prospective observational cohort study
Memphis, Tennessee and Pittsburgh, Pennsylvania
1,862 Health, Aging and Body Composition study participants aged 70 to 79 years without mobility limitations at the Year 3 visit.
Vision was measured at the Year 3 visit and visual impairment was defined as: 1) distance visual acuity worse than 20/40, 2) contrast sensitivity <1.55 logContrast, and 3) stereoacuity >85 seconds of arc. Incident persistent walking and stair climbing limitation was defined as two consecutive 6-month reports of any difficulty walking ¼ mile or walking up 10 steps after 1, 3, and 5 years of follow-up.
At Year 3 (baseline for these analyses), 7.4%, 27.2% and 29.2% had impaired visual acuity, contrast sensitivity, and stereoacuity, respectively. At all follow-up times, the incidence of walking and stair climbing limitations was higher in participants with visual acuity, contrast sensitivity, or stereoacuity impairment. After 5 years, impaired contrast sensitivity and stereoacuity were independently associated with a greater risk of walking limitation (HRcontrast sensitivity=1.3; 95% CI: 1.1–1.7; HRstereoacuity=1.3; 95% CI: 1.1–1.6), and stair climbing limitation (HRcontrast sensitivity=1.4; 95% CI: 1.1–1.8; HRstereoacuity=1.3; 95% CI: 1.1–1.7). Having both impaired contrast sensitivity and stereoacuity was associated with an increased risk of mobility limitations (HRwalking limitations = 2.0; 95% CI: 1.6–2.5; HRstair limitations=2.1; 95% CI: 1.6–2.8).
Findings suggest that multiple aspects of visual impairment may contribute to mobility limitations in older adults. Addressing more than one component of vision may be needed to reduce the impact of vision impairment on functional decline.
Visual impairment; mobility; physical functioning
Peripheral nerve impairments are highly prevalent in older adults and are associated with poor lower-extremity function. Whether sensorimotor nerve function predicts incident mobility disability has not been determined. We assessed the relationship between sensorimotor nerve function and incident mobility disability over 10 years.
Prospective cohort study with longitudinal analysis.
Two U.S. clinical sites.
Population-based sample of community-dwelling older adults with no mobility disability at 2000/01 exam (N = 1680; mean ± SD: age = 76.5 ± 2.9, BMI = 27.1 ± 4.6; 50.2% women, 36.6% black and 10.7% with diabetes).
Motor nerve conduction amplitude (poor: <1 mV) and velocity (poor: <40 m/s) were measured on the deep peroneal nerve. Sensory nerve function was measured using 10-g and 1.4-g monofilaments and vibration detection threshold at the toe. Lower-extremity symptoms included numbness or tingling and sudden stabbing, burning, pain or aches. Incident mobility disability assessed semiannually over 8.5 years (IQR: 4.5–9.6) was defined as two consecutive self-reports of a lot of difficulty or inability to walk ¼ mile or climb 10 steps.
Nerve impairments were detected in 55% of participants and 30% developed mobility disability. Worse motor amplitude (HR = 1.29 per SD, 95% CI: 1.16–1.44), vibration detection threshold (HR = 1.13 per SD, 95% CI: 1.04–1.23), symptoms (HR = 1.65, 95% CI: 1.36–2.17), 2 motor (HR = 2.10, 95% CI: 1.43–3.09), 2 sensory (HR = 1.91, 95% CI: 1.37–2.68), and ≥3 nerve impairments (HR = 2.33, 95% CI: 1.54–3.53) predicted incident mobility disability, after adjustment. Quadriceps strength mediated relationships between certain nerve impairments and mobility disability, although most remained significant.
Poor sensorimotor nerve function independently predicted mobility disability. Future work should investigate modifiable risk factors and interventions like strength training for preventing disability and improving function in older adults with poor nerve function.
Peripheral nerve function; disability; older adults; longitudinal analysis; muscle strength
We aimed to examine trajectories of inflammatory markers and cognitive decline over 10 years. Cox proportional hazards models were used to examine the association between interleukin-6 (IL-6) and C-reactive protein (CRP) trajectory components (slope, variability, and baseline level) and cognitive decline among 1,323 adults, age 70 to 79 years in the Health, Aging and Body Composition Study. We tested for interactions by sex and apolipoprotein E (APOE) genotype. In models adjusted for multiple covariates and comorbidities, extreme CRP variability was significantly associated with cognitive decline (HR 1.6, 95% CI: 1.1-2.3). This association was modified by sex and APOE e4 (p<0.001 for both), such that the association remained among women (HR=1.8; 95% CI: 1.1, 3.0) and among those with no APOE e4 allele (HR=1.6; 95% CI: 1.1, 2.5). There were no significant associations between slope or baseline level of CRP and cognitive decline, nor between IL-6 and cognitive decline. We believe CRP variability likely reflects poor control of or greater changes in vascular or metabolic disease over time, which in turn is associated with cognitive decline.
Inflammatory markers; cognitive decline; C-reactive protein; Interleukin-6
A positive association between cardiorespiratory fitness (CRF) and white matter integrity has been consistently reported in older adults. However, it is unknown whether this association exists in adults over 80 with a range of chronic disease conditions and low physical activity participation, which can influence both CRF and brain health. This study examined whether higher CRF was associated with greater microstructural integrity of gray and white matter in areas related to memory and information processing in adults over 80 and examined moderating effects of chronic diseases and physical activity. CRF was measured as time to walk 400m as quickly as possible with concurrent 3Telsa diffusion tensor imaging in 164 participants (57.1%female, 40.3%black). Fractional anisotropy (FA) was computed for cingulum, uncinate and superior longitudinal fasciculi. Mean diffusivity (MD) was computed for dorsolateral prefrontal cortex, hippocampus, parahippocampus, and entorhinal cortex. Moderating effects were tested using hierarchical regression models. Higher CRF was associated with higher FA in cingulum and lower MD in hippocampus and entorhinal cortex (β, sex-adjusted p: −0.182, 0.019; 0.165, 0.035; and 0.220, 0.006, respectively). Hypertension attenuated the association with MD in entorhinal cortex. Moderating effects of chronic diseases and physical activity in walking and climbing stairs on these associations were not significant. The association of higher CRF with greater microstructural integrity in selected subcortical areas appears robust, even among very old adults with a range of chronic diseases. Intervention studies should investigate whether increasing CRF can preserve memory and information processing by improving microstructure and potential effects of hypertension management.
Cardiorespiratory Fitness; Diffusion Tensor Imaging; Microstructural Integrity; Very Old Adults; Neuroepidemiology
Although it is generally accepted that anticholinergic use may lead to a fall, results from studies assessing the association between anticholinergic use and falls are mixed. In addition, direct evidence of an association between use of anticholinergic medications and recurrent falls among community-dwelling elders is not available.
To assess the association between anticholinergic use across multiple anticholinergic subclasses, including over-the-counter medications, and recurrent falls.
This was a longitudinal analysis of 2948 participants, with data collected via interview at year 1 from the Health, Aging and Body Composition study and followed through year 7 (1997–2004). Self-reported use of anticholinergic medication was identified at years 1, 2, 3, 5, and 6 as defined by the list from the 2015 American Geriatrics Society Beers Criteria. Dosage and duration were also examined. The main outcome was recurrent falls (≥2) in an ensuing 12-month period from each medication data collection.
Using multivariable generalized estimating equation models, controlling for demographic, health status/behaviors, and access-to-care factors, a 34% increase in likelihood of recurrent falls in anticholinergic users (adjusted odds ratio = 1.34; 95% CI = 0.93–1.93) was observed, but the results were not statistically significant; similar results were found with higher doses and longer duration of use.
Increased point estimates suggest an association of anticholinergic use with recurrent falls, but the associations did not reach statistical significance. Future studies are needed for more definitive evidence and to examine other measures of anticholinergic burden and associations with more intermediate adverse effects such as cognitive function.
cholinergic antagonist; accidental falls; older adults; pharmacoepidemiology
There is no gold standard to assess potential anticholinergic burden of medications.
To evaluate concordance among five commonly used anticholinergic scales.
Cross-sectional secondary analysis.
Pittsburgh, PA, and Memphis, TN.
3,055 community-dwelling older adults aged 70–79 with baseline medication data from the Health, Aging, and Body Composition study.
Any use, weighted scores, and total standardized daily dosage were calculated using five anticholinergic measures (i.e., Anticholinergic Cognitive Burden [ACB] Scale, Anticholinergic Drug Scale [ADS], Anticholinergic Risk Scale [ARS], Drug Burden Index anticholinergic component [DBI-ACh], and Summated Anticholinergic Medications Scale [SAMS]). Concordance was evaluated with kappa statistics and Spearman rank correlations.
Any anticholinergic use in rank order was 51% for the ACB, 43% for the ADS, 29% for the DBI-ACh, 23% for the ARS, and 16% for the SAMS. Kappa statistics for all pairwise use comparisons ranged from 0.33 to 0.68. Similarly, concordance as measured by weighted kappa statistics ranged from 0.54 to 0.70 among the three scales not incorporating dosage (ADS, ARS, and ACB). Spearman rank correlation between the DBI-ACh and SAMS was 0.50.
Only low to moderate concordance was found among the five anticholinergic scales. Future research is needed to examine how these differences in measurement impact their predictive validity with respect to clinically relevant outcomes, such as cognitive impairment.
cholinergic antagonists; aged; drug utilization
Non-steroidal anti-inflammatory drug (NSAID) use is a major risk factor for peptic ulcer disease (PUD) in older adults; thus, a gastroprotective agent is recommended in high-risk patients. This study of older daily NSAID users examined whether gastroprotective agent underuse decreased over time.
Health, Aging and Body Composition study.
Daily users of an NSAID (prescription and over-the-counter [OTC]) at the 2002–03 (pre-period; n=404) and 2006–07 (post-period; n=172) visits. The sample had a mean (standard deviation [±SD]) age of 78.2 [±2.7] years and 81.9 [±2.7] years at the visits, respectively. The majority were white, women and with ≥12 years of education.
Underusers were defined as: (1) persons taking non-selective NSAIDs at risk of PUD (due to current warfarin or glucocorticoid use, or history of PUD) and not using a proton pump inhibitor, or (2) COX-2 selective NSAID users taking aspirin at risk of PUD (i.e., having at least one risk factor) and not using a proton pump inhibitor.
Daily NSAID use decreased from 17.6% to 11.3% (p<0.001), and gastroprotective agent underuse decreased from 23.5% and 15.1% (p=0.008) over time. Controlling for important covariates, having prescription insurance was somewhat protective from underuse in the pre-period (adjusted odds ratio [AOR] 0.78, 95% confidence interval [CI] 0.46–1.34; p=0.37), but more so and significantly in the post-period (AOR 0.41, 95% CI 0.18–0.93; p=0.03). Over time, having prescription insurance was more protective in the post versus pre-period (i.e., less gastroprotective agent underuse; adjusted ratio of OR 0.53, 95% CI 0.22–1.29; p=0.16), but this increased protection was not statistically significant.
Among high-risk older daily NSAID users, having prescription insurance and adequate gastroprotective use was more common in the post than in the pre-period.
NSAID; older adults; gastroprotection
Age-related declines in physical activity are commonly observed in human and animal populations, but their physiological bases are not fully understood. We hypothesize that a lack of available energy contributes to low levels of activity in older persons.
Cross-sectional analyses of relationships between physical activity level and energy availability were performed in 602 community-dwelling volunteers aged 45 to 91 yrs from the Baltimore Longitudinal Study of Aging (BLSA). Energy expenditure was measured at rest and during a maximal 400-meter walk for calculation of “available energy.” Overall and vigorous physical activity levels were assessed using standardized questionnaires. General linear regression models were used to assess the relationships between available energy and general and vigorous physical activity, and stratified analyses were used to analyze the possible differential association between available energy and physical activity across high and low (peak sustained walking VO2 <18.3 ml O2/kg/min) levels of aerobic fitness.
Low available energy was associated with low levels of total physical activity (β = 64.678, p = .015) and vigorous activity (β = 9.123, p < .0001). The direct relationship between available energy and physical activity was particularly strong in persons categorized as having low aerobic fitness between available energy and physical activity with both total (β = 119.783, p = .022) and vigorous activity (β = 10.246, p = .015) and was independent of body composition and age.
Findings from this study support the hypothesis that available energy promotes the maintenance of physical activity in older persons. The findings also run counter to the perception that age-related declines in physical activity are primarily societally or behaviorally driven.
Physical Activity; Energy; Aging; Aerobic Fitness
Although the beneficial effects of physical activity (PA) on memory and executive function are well established in older adults, little is known about the relationship between PA and brain microstructure and the contributions of physical functional limitations and chronic diseases. This study examined whether higher PA would be longitudinally associated with greater microstructural integrity in memory- and executive function-related networks and whether these associations would be independent of physical function and chronic diseases.
Diffusion tensor imaging was obtained in 2006–2008 in 276 participants (mean age = 83.0 years, 58.7% female, 41.3% black) with PA (sedentary, lifestyle active, and exercise active) measured in 1997–1998. Gait speed, cognition, depressive symptoms, cardiovascular and pulmonary diseases, hypertension, stroke, and diabetes were measured at both time points. Mean diffusivity and fractional anisotropy were computed from normal-appearing gray and white matter in frontoparietal and subcortical networks. Moderating effects of physical function and chronic diseases were tested using hierarchical regression models.
Compared with the sedentary, the exercise active group had lower mean diffusivity in the medial temporal lobe and the cingulate cortex (β, p values: −.405, .023 and −.497, .006, respectively), independent of age, sex, and race. Associations remained independent of other variables, although they were attenuated after adjustment for diabetes. Associations between PA and other neuroimaging markers were not significant.
Being exercise active predicts greater memory-related microstructural integrity in older adults. Future studies in older adults with diabetes are warranted to examine the neuroprotective effect of PA in these networks.
Brain aging; Physical activity; Neuroimaging; Epidemiology.
Health risks associated with subclinical hypothyroidism in older adults are unclear.
To compare the functional mobility of seventy-year-olds by thyroid function categorized by thyroid stimulating hormone (TSH) level as euthyroid (0.4 mU/L< TSH <4.5 mU/L) or having mild (4.5 mU/L≥ TSH <7.0 mU/L) or moderate subclinical hypothyroidism (7.0 mU/L≤ TSH ≤20.0 mU/L with normal FT4) cross-sectionally and over two years.
Design, Setting, and Participants
2,290 community residents participating in the Year 2 clinic visit (July 1998-June 1999) of the Health, Aging and Body Composition study with measured TSH, capacity to walk 20 meters unaided and not taking thyroid medication or having TSH levels consistent with hyper- or hypothyroidism.
Main Outcome Measures
Self-reported and performance-based measures of mobility (usual and rapid gait speed and endurance walking ability) assessed at study baseline (Year 2) and two years later.
In age- and sex-adjusted analyses the mild subclinical hypothyroid group demonstrated better mobility – faster usual and rapid gait speed (1.20 vs. 1.15 m/s and 1.65 vs. 1.56 m/s; p<.001) and higher percent with good cardiorespiratory fitness and reported walking ease (39.2 vs. 28.0 and 44.7 vs. 36.5; p<.001). After two years, persons with mild subclinical hypothyroidism experienced similar decline as the euthyroid, but maintained their mobility advantage. Persons with moderate subclinical hypothyroidism had similar mobility and decline as the euthyroid group.
Generally well-functioning seventy-year-olds with subclinical hypothyroidism do not demonstrate increased risk of mobility problems and those with mild elevations in TSH show a slight functional advantage.
A new body adiposity index (BAI = (hip circumference)/((height)1.5) − 18) has been developed and validated in adult populations. We aimed to assess the validity of BAI in an older population. We compared the concordance correlation coefficient between BAI, body mass index (BMI), and percent body fat (fat%; by dual-energy X-ray absorptiometry) in an older population (n = 954) participating in the Baltimore Longitudinal Study of Aging. BAI was more strongly correlated with fat% than BMI (r of .7 vs .6 for BAI vs BMI and fat%, respectively, p < .01) and exhibited a smaller mean difference from fat% (−5.2 vs −7.6 for BAI vs BMI and fat%, respectively, p < .01) indicating better agreement. In men, however, BMI was in better agreement with fat% (r of .6 vs .7 for BAI vs BMI and fat%, respectively, p < .01) with a smaller mean difference from fat% (−3.0 vs −2.2 for BAI vs BMI and fat%, respectively, p < .01). Finally, BAI did not accurately predict fat% in people with a fat% below 15%. BAI provides valid estimation of body adiposity in an older adult population; however, BMI may be a better index for older men. Finally, BAI is not accurate in people with extremely low or high body fat percentages.
Body adiposity; BMI; Older population.
To identify clinical measures that aid detection of impending severe mobility difficulty in older women.
Cross-sectional and longitudinal cohort study.
Urban community in Baltimore, Maryland.
One thousand two community-dwelling, moderate to severely disabled women aged 65 and older in the Women’s Health and Aging Study I.
Self-report and performance measures representing six domains necessary for mobility: central and peripheral nervous systems, muscles, bones and joints, perception, and energy. Severe mobility difficulty was defined as usual gait of 0.5 m/s or less, any reported difficulty walking across a small room, or dependence on a walking aid during a 4-m walking test.
Four hundred sixty-seven out of 984 (47%) had severe mobility difficulty at baseline, and 104/474 (22%) developed it within 12 months. Baseline mobility difficulty was correlated with poor vision, knee pain, feelings of helplessness, inability to stand with feet side by side for 10 seconds, difficulty keeping balance while dressing or walking, inability to rise from a chair five times, and cognitive impairment. Of these, knee pain (odds ratio (OR) = 1.74, 95% confidence interval (CI) = 1.05–2.89), helplessness (OR = 1.87, 95% CI = 1.10–3.24), poor vision (OR = 2.03, 95% CI = 1.06–3.89), inability to rise from a chair five times (OR = 2.50, 95% CI = 1.15–5.41), and cognitive impairment (OR = 4.75, 95% CI = 1.67–13.48) predicted incident severe mobility difficulty within 12 months, independent of age.
Five simple measures may aid identification of disabled older women at high risk of severe mobility difficulty. Further studies should determine generalizability to men and higher-functioning individuals.
aging; mobility difficulty; clinical assessment
In spite of evidence that physical activity has beneficial effects on health and age-related functional decline, there is a scarcity of detailed and accurate information on objectively measured daily activity and patterns of such activity in older adults.
Participants in the Baltimore Longitudinal Study of Aging (n = 611, 50% male, mean age 67, range 32–93) wore the Actiheart portable activity monitor for 7 days in the free-living environment. The association between activity and age was modeled using a continuous log-linear regression of activity counts on age with sex, body mass index, employment status, functional performance, and comorbid conditions as covariates.
In the fully adjusted model, continuous analyses demonstrated that overall physical activity counts were 1.3% lower for each year increase in age. Although there were no differences among morning levels of activity, there was significantly lower afternoon and evening activity in older individuals (p < .01). After adjusting for age, poor functional performance, nonworking status, and higher body mass index were independently associated with less physical activity (p < .001).
The use of accelerometers to characterize minute-by-minute intensity, cumulative physical activity counts, and daily activity patterns provides detailed data not gathered by traditional subjective methods, particularly at low levels of activity. The findings of a 1.3% decrease per year in activity from mid-to-late life, and the corresponding drop in afternoon and evening activity, provide new information that may be useful when targeting future interventions. Further, this methodology addresses essential gaps in understanding activity patterns and trends in more sedentary sectors of the population.
Epidemiology; Functional performance; Physical activity; Public health.
To examine associations between weight change, body composition, risk of mobility disability and mortality in older adults.
Prospective, longitudinal, population-based cohort.
The Health ABC Study.
Women (n=1044) and men (n=931) aged 70-79.
Weight,lean and fat mass from DXA measured annually over 5 years. Weight was defined as stable (n=664, referent group), loss (n=662), gain (n=321) or cycling (gain and loss, n=328) using change of 5% from year to year or from year 1 to 6. Mobility disability (two consecutive reports of difficulty walking one-quarter mile or climbing 10 steps) and mortality were determined for 8 years subsequent to the weight change period. Associations were analyzed with cox proportional hazards regression adjusted for covariates.
During follow-up, 313 women and 375 men developed mobility disability,322 women and 378 men were deceased. There was no risk of mobility disability or mortality with weight gain. Weight loss and weight cycling were associated with mobility disability in women:hazard ratio (HR)=1.88 (95% confidence interval (CI)=1.40-2.53),HR=1.59 (95% CI=1.11-2.29) and weight loss was associated in men:HR=1.30 (95% CI=1.01-1.69).Weight loss and weight cycling were associated with mortality risk in women:HR=1.47 (95% CI=1.07-2.01), HR=1.62 (95% CI=1.15-2.30) and in men:HR=1.41 (95% CI=1.09-1.83),HR=1.50 (95% CI=1.08-2.08). Adjustment for lean and fat mass and change in lean and fat mass from year 1 to 6 attenuated relationships between weight loss and mobility disability in men, and weight loss and mortality in men and women.
Weight cycling and weight loss predict impendingmobility disability and mortality in old age, underscoring the prognostic importance of weight history.
Aging; obesity; physical function; body composition; muscle loss
Low literacy is common among the elderly and possibly more reflective of educational attainment than years of school completed. We examined the association between literacy and risk of likely dementia in older adults.
Participants were 2,458 black and white elders (aged 71–82) from the Health, Aging and Body Composition study, who completed the Rapid Estimate of Adult Literacy in Medicine and were followed for 8 years. Participants were free of dementia at baseline; incidence of likely dementia was defined by hospital records, prescription for dementia medication, or decline in Modified Mini-Mental State Examination score. We conducted Cox proportional hazard models to evaluate the association between literacy and incidence of likely dementia. Demographics, education, income, comorbidities, lifestyle variables, and apolipoprotein E (APOE) ε4 status were included in adjusted analyses.
Twenty-three percent of participants had limited literacy (<9th-grade level). Limited literacy, as opposed to adequate literacy (≥9th-grade level), was associated with greater incidence of likely dementia (25.5% vs17.0%; unadjusted hazard ratio [HR] = 1.75, 95% confidence interval 1.44–2.13); this association remained significant after adjustment. There was a trend for an interaction between literacy and APOE ε4 status (p = .07); the association between limited literacy and greater incidence of likely dementia was strong among ε4 noncarriers (unadjusted HR = 1.85) but nonsignificant among ε4 carriers (unadjusted HR = 1.25).
Limited literacy is an important risk factor for likely dementia, especially among APOE ε4-negative older adults, and may prove fruitful to target in interventions aimed at reducing dementia risk.
Cognitive aging; Risk factors; Epidemiology.