A roadmap to build a phenotypic metric of ageing: insights from the Baltimore Longitudinal Study of Aging.

Over the past three decades, considerable effort has been dedicated to quantifying the pace of ageing yet identifying the most essential metrics of ageing remains challenging due to lack of comprehensive measurements and heterogeneity of the ageing processes. Most of the previously proposed metrics of ageing have been emerged from cross-sectional associations with chronological age and predictive accuracy of mortality, thus lacking a conceptual model of functional or phenotypic domains. Further, such models may be biased by selective attrition and are unable to address underlying biological constructs contributing to functional markers of age-related decline. Using longitudinal data from the Baltimore Longitudinal Study of Aging (BLSA), we propose a conceptual framework to identify metrics of ageing that may capture the hierarchical and temporal relationships between functional ageing, phenotypic ageing and biological ageing based on four hypothesized domains: body composition, energy regulation, homeostatic mechanisms and neurodegeneration/neuroplasticity. We explored the longitudinal trajectories of key variables within these phenotypes using linear mixed-effects models and more than 10 years of data. Understanding the longitudinal trajectories across these domains in the BLSA provides a reference for researchers, informs future refinement of the phenotypic ageing framework and establishes a solid foundation for future models of biological ageing.

A prospective study of focal brain atrophy, mobility and fitness.

BACKGROUND: The parallel decline of mobility and cognition with ageing is explained in part by shared brain structural changes that are related to fitness. However, the temporal sequence between fitness, brain structural changes and mobility loss has not been fully evaluated. METHODS: Participants were from the Baltimore Longitudinal Study of Aging, aged 60 or older, initially free of cognitive and mobility impairments, with repeated measures of fitness (400-m time), mobility (6-m gait speed) and neuroimaging markers over 4 years (n = 332). Neuroimaging markers included volumes of total brain, ventricles, frontal, parietal, temporal and subcortical motor areas, and corpus callosum. Autoregressive models were used to examine the temporal sequence of each brain volume with mobility and fitness, adjusted for age, sex, race, body mass index, height, education, intracranial volume and APOE ɛ4 status. RESULTS: After adjustment, greater volumes of total brain and selected frontal, parietal and temporal areas, and corpus callosum were unidirectionally associated with future faster gait speed over and beyond cross-sectional and autoregressive associations. There were trends towards faster gait speed being associated with future greater hippocampus and precuneus. Higher fitness was unidirectionally associated with future greater parahippocampal gyrus and not with volumes in other areas. Smaller ventricle predicted future higher fitness. CONCLUSION: Specific regional brain volumes predict future mobility impairment. Impaired mobility is a risk factor for future atrophy of hippocampus and precuneus. Maintaining fitness preserves parahippocampal gyrus volume. Findings provide new insight into the complex and bidirectional relationship between the parallel decline of mobility and cognition often observed in older persons.

Contributions to lateral balance control in ambulatory older adults.

BACKGROUND: In older adults, impaired control of standing balance in the lateral direction is associated with the increased risk of falling. Assessing the factors that contribute to impaired standing balance control may identify areas to address to reduce falls risk. AIM: To investigate the contributions of physiological factors to standing lateral balance control. METHODS: Two hundred twenty-two participants from the Pittsburgh site of the Health, Aging and Body Composition Study had lateral balance control assessed using a clinical sensory integration balance test (standing on level and foam surface with eyes open and closed) and a lateral center of pressure tracking test using visual feedback. The center of pressure was recorded from a force platform. Multiple linear regression models examined contributors of lateral control of balance performance, including concurrently measured tests of lower extremity sensation, knee extensor strength, executive function, and clinical balance tests. Models were adjusted for age, body mass index, and sex. RESULTS: Larger lateral sway during the sensory integration test performed on foam was associated with longer repeated chair stands time. During the lateral center of pressure tracking task, the error in tracking increased at higher frequencies; greater error was associated with worse executive function. The relationship between sway performance and physical and cognitive function differed between women and men. DISCUSSION: Contributors to control of lateral balance were task-dependent. Lateral standing performance on an unstable surface may be more dependent upon general lower extremity strength, whereas visual tracking performance may be more dependent upon cognitive factors. CONCLUSIONS: Lateral balance control in ambulatory older adults is associated with deficits in strength and executive function.

Potential drug-drug and drug-disease interactions in well-functioning community-dwelling older adults.

WHAT IS KNOWN AND OBJECTIVE: There are few studies examining both drug-drug and drug-disease interactions in older adults. Therefore, the objective of this study was to describe the prevalence of potential drug-drug and drug-disease interactions and associated factors in community-dwelling older adults. METHODS: This cross-sectional study included 3055 adults aged 70-79 without mobility limitations at their baseline visit in the Health Aging and Body Composition Study conducted in the communities of Pittsburgh PA and Memphis TN, USA. The outcome factors were potential drug-drug and drug-disease interactions as per the application of explicit criteria drawn from a number of sources to self-reported prescription and non-prescription medication use. RESULTS: Over one-third of participants had at least one type of interaction. Approximately one quarter (25·1%) had evidence of had one or more drug-drug interactions. Nearly 10·7% of the participants had a drug-drug interaction that involved a non-prescription medication. % The most common drug-drug interaction was non-steroidal anti-inflammatory drugs (NSAIDs) affecting antihypertensives. Additionally, 16·0% had a potential drug-disease interaction with 3·7% participants having one involving non-prescription medications. The most common drug-disease interaction was aspirin/NSAID use in those with history of peptic ulcer disease without gastroprotection. Over one-third (34·0%) had at least one type of drug interaction. Each prescription medication increased the odds of having at least one type of drug interaction by 35-40% [drug-drug interaction adjusted odds ratio (AOR) = 1·35, 95% confidence interval (CI) = 1·27-1·42; drug-disease interaction AOR = 1·30; CI = 1·21-1·40; and both AOR = 1·45; CI = 1·34-1·57]. A prior hospitalization increased the odds of having at least one type of drug interaction by 49-84% compared with those not hospitalized (drug-drug interaction AOR = 1·49, 95% CI = 1·11-2·01; drug-disease interaction AOR = 1·69, CI = 1·15-2·49; and both AOR = 1·84, CI = 1·20-2·84). WHAT IS NEW AND CONCLUSION: Drug interactions are common among community-dwelling older adults and are associated with the number of medications and hospitalization in the previous year. Longitudinal studies are needed to evaluate the impact of drug interactions on health-related outcomes.

Apical periodontitis and incident cardiovascular events in the Baltimore Longitudinal Study of Ageing.

AIM: To evaluate whether the presence of apical periodontitis (AP), root canal treatment (RCT) and endodontic burden (EB) - as the sum of AP and RCT sites - were associated with long-term risk of incident cardiovascular events (CVE), including cardiovascular-related mortality, using data on participants in the Baltimore Longitudinal Study of Ageing (BLSA). METHODOLOGY: This retrospective cohort included 278 dentate participants in the BLSA with complete medical and dental examinations. Periodontal disease (PD) and missing teeth were recorded. The total number of AP and RCT sites was determined from panoramic radiographs. EB was calculated as the sum of AP and RCT sites. Oral inflammatory burden (OIB) was calculated combining PD and EB. The main outcome was incident CVE including angina, myocardial infarction and cardiovascular-related death. Participants were monitored for up to 44 years (mean = 17.4± 11.1 years) following dental examination. Relative risks (RRs) were calculated through Poisson regression models, estimating the relationship between AP, RCT, EB, PD, OIB and incident CVE. RESULTS: Mean age at baseline was 55.0 ±16.8 years and 51.4% were men. Sixty-two participants (22.3%) developed CVE. Bivariate analysis showed that PD, EB, number of teeth and OIB were associated with incident CVE. Multivariate models, adjusted for socio-demographic and medical variables, showed that age ≥60 years (RR = 3.07, 95% CI =1.68-5.62), hypertension (RR = 2.0, 95% CI = 1.16-3.46) and EB ≥3 (RR = 1.77, 95% CI = 1.04-3.02) were independently associated with incident CVE. The association between OIB and incident CVE was reduced to nonsignificance after adjustments (RR = 1.97, 95% CI = 0.83-4.70). CONCLUSIONS: EB in midlife was an independent predictor of CVE amongst community-dwelling participants in the BLSA. Prospective studies are required to evaluate cardiovascular risk reduction with the treatment of AP.

Sex-specific differences in progressive glucose intolerance and hip geometry: the Baltimore Longitudinal Study of Aging.

UNLABELLED: Fracture risk is increased in type 2 diabetes mellitus (T2DM). The effect of pre-diabetes and T2DM on bone macroarchitecture and strength has not been well investigated. In this study, we show that in women only, both pre-diabetes and T2DM are associated with decreased hip bending strength and mineralization which might lead to skeletal weakness. INTRODUCTION: Older men and women with T2DM are at increased risk for fracture despite normal bone mineral density (BMD). The discordance between bone quantity and skeletal fragility has driven investigation into additional determinants of fracture resistance in T2DM. Additionally, the effect of pre-diabetes on bone strength has not been well described. The aim of this study was to determine differences in bone macroarchitecture and strength, measured by hip geometry, in persons with normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and T2DM. METHODS: We performed cross-sectional analyses of older (age >55 years) men (n = 472) and women (n = 473) participating in the Baltimore Longitudinal Study of Aging (BLSA) classified as NGT, IGT, or T2DM based on oral glucose tolerance testing. Bone strength measures included the hip geometry parameters of section modulus (Z), cross-sectional area (CSA), and buckling ratio (BR). Sex-stratified analyses were conducted using adjusted stepwise regression models. RESULTS: In women, IGT and T2DM were negatively associated with hip geometry parameters including mineralization in cross section (CSA, ß -0.076 and -0.073, respectively; both p < 0.05) and hip bending strength (Z, ß -0.097 and -0.09, respectively; both p < 0.05); conversely, IGT and T2DM were associated with improved compressive strength (BR, ß -0.31 and -0.29, respectively; both p < 0.05). There was no significant association between glycemic status and hip geometry in men. CONCLUSIONS: In women only, both IGT and T2DM were inversely associated with bone macroarchitecture and measures of bone mineralization and bending strength. The same association between worsening glycemic status and bone strength was not observed in men. These data suggest a differential effect of sex on hip geometry with evolving glucose intolerance.

Association between vestibular function and rotational spatial orientation perception in older adults.

BACKGROUND: Spatial orientation is a complex process involving vestibular sensory input and possibly cognitive ability. Previous research demonstrated that rotational spatial orientation was worse for individuals with profound bilateral vestibular dysfunction. OBJECTIVE: Determine whether rotational and linear vestibular function were independently associated with large amplitude rotational spatial orientation perception in healthy aging. METHODS: Tests of rotational spatial orientation accuracy and vestibular function [vestibulo-ocular reflex (VOR), ocular and cervical vestibular evoked myogenic potentials (VEMP)] were administered to 272 healthy community-dwelling adults participating in the Baltimore Longitudinal Study of Aging. Using a mixed model multiple linear regression we regressed spatial orientation errors on lateral semicircular canal function, utricular function (ocular VEMP), and saccular function (cervical VEMP) in a single model controlling for rotation size, age, and sex. RESULTS: After adjusting for age, and sex, individuals with bilaterally low VOR gain (ß= 20.9, p = 0.014) and those with bilaterally absent utricular function (ß= 9.32, p = 0.017) made significantly larger spatial orientation errors relative to individuals with normal vestibular function. CONCLUSIONS: The current results demonstrate for the first time that either bilateral lateral semicircular canal dysfunction or bilateral utricular dysfunction are associated with worse rotational spatial orientation. We also demonstrated in a healthy aging cohort that increased age also contributes to spatial orientation ability.

Cognitive ability is associated with suspected reporting errors on food frequency questionnaires.

OBJECTIVE: To examine potential for bias in reported total energy intake on a Food Frequency Questionnaire (FFQ) among older adults. DESIGN: Longitudinal cohort study. SUBJECTS/SETTING: 2,706 Community-dwelling Black and White older adults, aged 70-79 years, enrolled in the Health, Aging, and Body Composition study. Multivariate logistic regression analyses were conducted with potential errors on reported total energy intake on the Food Frequency Questionnaire (FFQ) as the outcome variable and with cognitive ability, measured by the Modified Mini Mental State Exam (3MS) as the primary independent variable. The regression model controlled for site, race, gender, age, body size, and physical activity. Separate models were fit using 3MS as a continuous variable and for multiple 3MS cutpoints. All models revealed similar findings. RESULTS: Cognitive ability was inversely associated with potential errors in reporting total energy intake, whereby a five-point increase in 3MS scores was associated with a 14% decreased likelihood of reporting errors (Odds Ratio=0.86, 95% Confidence Interval: 0.77, 0.95). Additionally, compared to White women, White men were 2 times more likely, and Black women and Black men were 3 times more likely, to have errors in reporting total energy intake. CONCLUSION: This study provides evidence that for older adults, lower cognition scores are associated with increased potential errors in reporting total energy intake. APPLICATIONS: Dietary reporting from older adults may be inaccurate due to cognitive deficits. A brief assessment of cognitive function may assist clinicians in dietary evaluations and recommendation and may benefit studies using FFQ data where the measure of cognitive function could be utilized to stratify data analyses and conduct sensitivity analyses.

Vitamin B12 and Homocysteine Associations with Gait Speed in Older Adults: The Baltimore Longitudinal Study of Aging.

OBJECTIVES: This study aimed to assess the independent associations of serum levels of vitamin B12 and plasma concentrations of homocysteine with gait speed decline. DESIGN, SETTING, PARTICIPANTS: This study utilized longitudinal analysis of participants 50 years or older from The Baltimore Longitudinal Study of Aging, N=774. MEASUREMENTS: Gait speed (m/s) was assessed using the 6-meter usual pace test. Vitamin B12 and homocysteine concentrations were collected using standard clinical protocols. Linear mixed effects regression was stratified by baseline age category (50-69, 70-79, and ≥80 years old). RESULTS: Mean follow-up time for the total study sample was 5.4 ± 2.0 years. No association between vitamin B12 and gait speed decline over the follow-up time for any age group was found. Elevated homocysteine concentrations were associated with decline in gait speed after adjustment for covariates (50-69: ß= -0.005, p=.057; 70-79: ß= -0.013, p<.001, ≥80: ß= -0.007, p=.054). CONCLUSION: Homocysteine and vitamin B12 are inversely related, yet only homocysteine was associated with gait speed decline in this population of healthy older adults. Given these results, future research should be directed towards investigating the relationship in populations with greater variation in vitamin B12 concentrations and other mechanisms influencing homocysteine concentrations.

Muscle Quality, Strength, and Lower Extremity Physical Performance in the Baltimore Longitudinal Study of Aging.

BACKGROUND: Muscle quality is defined as the force generated by each volumetric unit of muscle tissue. No consensus exists on an optimal measure of muscle quality, impeding comparison across studies and implementation in clinical settings. It is unknown whether muscle quality measures that rely on complex and expensive tests, such as isokinetic dynamometry and computerized tomography correlate with lower extremity performance (LEP) any better than measures derived from simpler and less expensive tests, such as grip strength (Grip) and appendicular lean mass (ALM) assessed by DXA. Additionally, whether muscle quality is more strongly associated with LEP than strength has not been fully tested. OBJECTIVES: This study compares the concurrent validity of alternative measures of muscle quality and characterizes their relationship with LEP. We also whether muscle quality correlates more strongly with LEP than strength alone. DESIGN: Cross-sectional analysis. SETTING: Community. PARTICIPANTS: 365 men and 345 women 65 years of age and older in the Baltimore Longitudinal Study of Aging. MEASURES: Thigh cross-sectional area (TCSA), isokinetic and isometric knee extension strength (ID), BMI adjusted ALM (ALMBMI) from DXA, and Grip. Concurrent validity was assessed as the percent variance of different measures of LEP explained by each muscle quality measure. In addition, we compared LEP relationships between each measure of strength and its correspondent value of muscle quality. Confidence intervals for differences in percent variance were calculated by bootstrapping. RESULTS: Grip/ALMBMI explained as much variance as ID/TCSA across all LEP measures in women and most in men. Across all LEP measures, strength explained as much variance of LEP as muscle quality. CONCLUSIONS: Grip/ALMBMI and ID/TCSA measures had similar correlations with LEP. Muscle quality did not outperform strength. Although evaluating muscle quality may be useful to assess age-related mechanisms of change in muscle strength, measures of strength alone may suffice to understand the relationship between muscle and LEP.

Glycemia and cognitive function in older adults using glucose-lowering drugs.

OBJECTIVES: In experimental studies, both high and low levels of plasma glucose are associated with cognitive impairment. In populations, less is known about the relationship between glycemia and cognitive function, especially in persons using glucose-lowering drugs. DESIGN: A cross-sectional study of 378 high-functioning black and white men and women aged 70 to 79 participating in the Health, Aging, and Body Composition Study (Health ABC) who used glucose-lowering medications. Glycemic measures included fasting plasma glucose (FPG) and glycosylated hemoglobin (HbA1c). Cognitive function was assessed using the Modified Mini-Mental State Examination (3MS) and the Digit Symbol Substitution Test (DSS) at the same examination visit in which the glycemic measures were determined. SETTING: Memphis, Tennessee and Pittsburgh, Pennsylvania. RESULTS: We observed an "inverted-U" relationship (p =.0025 for 3MS, p=.0277 for DSS) between FPG (range 47 - 366 mg/dl) and performance on these two tests. The fasting plasma glucose levels associated with the highest score on the 3MS was 180 mg/dl and 135 mg/dl for the DSS. There was a monotonic inverse relationship between HbA1c and performance on 3MS and DSS without evidence of a threshold effect. CONCLUSION: Our findings suggest that older adults who are treated for diabetes may experience a small degree of cognitive impairment within the recommended fasting glucose levels, yet measures of long-term glycemic control support tight glycemic control. Given the high prevalence of diabetes and the common use of glucose-lowering drugs in older adults, further studies are needed to elucidate these relationships.

Effects of aromatase inhibition vs. testosterone in older men with low testosterone: randomized-controlled trial.

Aging in men is associated with loss of bone mass, impaired physical function and altered body composition. The objective of this proof-of-concept randomized, double-blind, placebo-controlled, parallel-group, single-center trial was to determine the relative effects of testosterone (T) and estradiol (E(2)) on bone mineral density, body composition, and physical performance in older men. The primary outcome was lumbar spine bone mineral density (BMD), and secondary outcomes were body composition, muscle strength, gait speed, and sex hormone concentrations. Forty three men (age range, 65-82 years; mean age 71 years) with low total T levels <350 ng/dL were randomized to one of three groups: 5 g transdermal testosterone gel (TT) (N = 16), anastrozole (AI) 1 mg (N = 14) or placebo daily (N = 13) for 12 months. Outcomes were assessed at baseline, 3, 6, and 12 months. Both TT and AI increased serum TT levels (>500 ng/dL, p < 0.05) compared to baseline; T values remained stable throughout the duration of the trial. At 12 months, TT improved the primary outcome of lumbar spine BMD (p < 0.01).Both interventions improved knee strength at 12 months compared to baseline (p < 0.05) while lean body mass significantly increased only in the AI group at 6 and 12 months (1.49 ± 0.38 kg, p < 0.01; 1.24 ± 0.39 kg, p < 0.05, respectively) compared to baseline. Interestingly, TT improved fast gait speed at 3 and 12 months (p < 0.01, p < 0.05, respectively). In summary, this proof-of-concept study confirms that aromatization of T is required for maintaining BMD in older men with low-T levels. The trial also uncovered the novel finding that aromatization of T is required for improvement in fast gait speed, an observation that needs to be verified in future studies.

Arterialized venous bicarbonate is associated with lower bone mineral density and an increased rate of bone loss in older men and women.

CONTEXT: Higher dietary net acid loads have been associated with increased bone resorption, reduced bone mineral density (BMD), and increased fracture risk. OBJECTIVE: The objective was to compare bicarbonate (HCO3) measured in arterialized venous blood samples to skeletal outcomes. DESIGN: Arterialized venous samples collected from participants in the Health, Aging and Body Composition (Health ABC) Study were compared to BMD and rate of bone loss. SETTING: The setting was a community-based observational cohort. PARTICIPANTS: A total of 2287 men and women age 74 ± 3 years participated. INTERVENTION: Arterialized venous blood was obtained at the year 3 study visit and analyzed for pH and pCO2. HCO3 was determined using the Henderson-Hasselbalch equation. MAIN OUTCOME MEASURE: BMD was measured at the hip by dual-energy x-ray absorptiometry at the year 1 (baseline) and year 3 study visits. RESULTS: Plasma HCO3 was positively associated with BMD at both year 1 (P = .001) and year 3 (P = .001) in models adjusted for age, race, sex, clinic site, smoking, weight, and estimated glomerular filtration rate. Plasma HCO3 was inversely associated with rate of bone loss at the total hip over the 2.1 ± 0.3 (mean ± SD) years between the two bone density measurements (P < .001). Across quartiles of plasma HCO3, the rate of change in BMD over the 2.1 years ranged from a loss of 0.72%/y in the lowest quartile to a gain of 0.15%/y in the highest quartile of HCO3. CONCLUSIONS: Arterialized plasma HCO3 was associated positively with cross-sectional BMD and inversely with the rate of bone loss, implying that systemic acid-base status is an important determinant of skeletal health during aging. Ongoing bone loss was linearly related to arterialized HCO3, even after adjustment for age and renal function. Further research in this area may have major public health implications because reducing dietary net acid load is possible through dietary intervention or through supplementation with alkaline potassium compounds.

Marked differences in antidepressant use by race in an elderly community sample: 1986-1996.

OBJECTIVE: Prescriptions of antidepressant medications have increased significantly over the past 15 years across the life cycle. One overall correlate of medication use in older adults is race, with African Americans using fewer medications than whites. Given the frequency of depressive symptoms among elderly populations, as well as the increased potential for adverse side effects from antidepressants, the relative contribution of race in the use of antidepressants is critical for determining well-designed studies. The authors analyzed data from a community-based cohort of elders followed for 10 years to determine the association of race to the use of antidepressants between 1986 and 1996, with control for known correlates of depression in late life. METHOD: Information on antidepressant use and demographic and health characteristics were obtained from a stratified, probability-based sample of 4,162 elders (equally distributed between African American and white community-dwelling subjects) in the Piedmont region of North Carolina during four in-person interviews spanning 10 years. Descriptive statistics were calculated. Logistic regression was used for the final models. RESULTS: A total of 4.6% of whites and 2.3% of African Americans used antidepressants in 1986. Approximately 14.3% of whites and 5.0% of African Americans used antidepressants in 1996. In controlled analyses, the prevalence odds ratio for antidepressant use in whites, compared to African Americans, was 1. 76 in 1986 and 3.77 in 1996. CONCLUSIONS: African American elders are much less likely to take antidepressants, and the difference in use increased over the 10 years of the survey.

Incidence and remission of insomnia among elderly adults: an epidemiologic study of 6,800 persons over three years.

To determine incidence and remission rates of insomnia in older adults and associated risk factors. Three-year longitudinal study, 1982-198--East Boston, MA; New Haven, CT; Iowa and Washington counties, IA. Participants were 6,899 men and women aged 65 years and older. Self-reported difficulty falling asleep or early morning arousal (insomnia), along with physician diagnosis of heart disease, stroke, cancer, diabetes, or hip-fracture, self-report of physical disability, depressive symptomatology, perceived health status, and use of medications ascertained at both baseline and three-year follow-up. Nearly 15% of the 4,956 participants without symptoms of insomnia at baseline reported chronic difficulty falling asleep or early morning arousal at follow-up, suggesting an annual incidence rate of approximately 5%. Incident insomnia was associated with depressed mood, respiratory symptoms, fair to poor perceived health, and physical disability. In multivariate analyses, these risk factors explained the higher incidence of insomnia among those with medical conditions such as heart disease, stroke, and diabetes. Other factors associated with an increased risk of insomnia included use of prescribed sedatives, and widowhood. Only 7% of the incident cases of insomnia occurred in the absence of associated risk factors. Of the nearly 2,000 survivors with chronic insomnia at baseline, almost half no longer reported symptoms upon follow-up and were more likely to report improved self-perceived health compared to those who continued to report symptoms. Chronic disease, depressed mood, physical disability, poor perceived health, widowhood, and use of sedatives are associated with development and remission of insomnia symptoms. Because the vast majority of incident cases of insomnia were among persons with one or more of these risk factors, these data do not support a model of incident insomnia caused by the aging process per se.

Sleep complaints among elderly persons: an epidemiologic study of three communities.

The frequencies of five common sleep complaints--trouble falling asleep, waking up, awaking too early, needing to nap and not feeling rested--were assessed in over 9,000 participants aged 65 years and older in the National Institute on Aging's multicentered study entitled "Established Populations for Epidemiologic Studies of the Elderly" (EPESE). Less than 20% of the participants in each community rarely or never had any complaints, whereas over half reported at least one of these complaints as occurring most of the time. Between 23% and 34% had symptoms of insomnia, and between 7% and 15% percent rarely or never felt rested after waking up in the morning. In multivariate analyses, sleep complaints were associated with an increasing number of respiratory symptoms, physical disabilities, nonprescription medications, depressive symptoms and poorer self-perceived health. Sleep disturbances, particularly among older persons, oftentimes may be secondary to coexisting diseases. Determining the prevalence of specific sleep disorders, independent of health status, will require the development of more sophisticated and objective measures of sleep disturbances.

Patient-proxy response comparability on measures of patient health and functional status.

The present study evaluates the response comparability between 361 elderly hip fracture patients admitted from the community to seven Baltimore area hospitals between 1984 and 1986 and interviewer selected proxies on items pertaining to patients' pre-fracture health and functional status. Agreement across items ranges from very poor to good and varies with respect to the health or functional area assessed. Proxies tend to overestimate patient disability relative to the patients themselves, especially with regard to capacity to perform instrumental activities of daily living. Although proxies who report the greatest contact with patients respond most comparably to the patients, when they do disagree, proxies with the greatest patient contact tend to overestimate patient disability. The authors suggest that attention to item construction and phrasing may improve response comparability.

Effect of age and severity of disability on short-term variation in walking speed: the Women's Health and Aging Study.

Standardized objective measures of human performance have been introduced in clinical and epidemiologic studies of older populations. Reliability of these measures has usually been estimated by comparing two measures obtained in the same person. However, no information is available on variability of multiple measures collected serially over short time intervals. This study uses data from the Weekly Disability Study, a component of the Women's Health and Aging Study, to describe fluctuations in physical performance over multiple, consecutive time intervals. Walking speed was measured weekly over a 6-month period in 99 older women affected by mild to severe disability. Overall, 2120 observations were explored using techniques developed for the analysis of repeated measures. Results showed that the correlations between observations in the same person were inversely related to their separation in time. The decay in the autocorrelation function was steeper in the least disabled. However, even with 20-week separations in assessments, correlations remained above 0.6 in all age and severity of disability subgroups. Changes over time in performance differed somewhat between disability subgroups, but the relative performance across subgroups remained stable over the entire course of the study. A clear learning effect was found only in those in the middle disability subgroup. Results support the utilization of repeated measures of physical performance in research that evaluates older persons over time.

The impact of insomnia on cognitive functioning in older adults.

OBJECTIVES: To examine whether self-reported symptoms of insomnia independently increase risk of cognitive decline in older adults. DESIGN: Longitudinal cohort study. SETTING: The four sites of the Established Populations for Epidemiologic Studies of the Elderly. PARTICIPANTS: Six thousand four hundred forty-four community-dwelling men and women age 65 and older who had no more than one error on the Short Portable Mental Status Questionnaire (SPMSQ) at baseline and an in-person interview at the third annual follow-up (FU3). MEASUREMENTS: Insomnia was defined as report of trouble falling asleep or waking up too early most of the time. Cognitive decline was defined as two or more errors on the SPMSQ at FU3. Logistic regression was used to determine risk of cognitive decline associated with insomnia, controlling for demographic, behavioral, and health-related factors. Analyses were stratified by sex and depressed mood. RESULTS: Among nondepressed men, those reporting symptoms of insomnia at both baseline and FU3 had an adjusted odds ratio (OR) of 1.49 (95% CI = 1.03-2.14) for cognitive decline, relative to those with no insomnia at FU3. Men with insomnia at FU3 only were not at increased risk (OR = 1.16, 95% CI = 0.82-1.65). These relationships were not found in women. Men and women with depressive symptoms at FU3 were at increased risk for cognitive decline independent of insomnia. CONCLUSION: Chronic insomnia independently predicts incident cognitive decline in older men. More sensitive measures of cognitive performance may identify more subtle declines and may confirm whether insomnia is associated with cognitive decline in women.

Equivalence of two screens of cognitive functioning: the Short Portable Mental Status Questionnaire and the Orientation-Memory-Concentration test.

OBJECTIVE: To determine the equivalence of two screens of cognitive functioning: the Short Portable Mental Status Questionnaire (SPMSQ) and the Orientation-Memory-Concentration (OMC) test. DESIGN: The design was cross-sectional and longitudinal. SETTING: Four rural and one urban county in the Piedmont region of North Carolina (n = 3210). PARTICIPANTS: A stratified random cluster sample (n = 3210) of people 68 years of age and older. MEASUREMENTS: SPMSQ and OMC at the fourth wave of the Duke Established Populations for Epidemiologic Studies of the Elderly (EPESE); disability, depression, and death measurements from the fourth through seventh waves of EPESE; demographic characteristics. RESULTS: On the SPMSQ and the OMC (r = .80), 15.3% and 38.4%, respectively, of those tested were rated cognitively impaired. Poorer scores were associated with older age, black race, and less education. These associations were attenuated on the dichotomized SPMSQ but not on the OMC. Both measures predicted disability and depressive symptomatology currently and 3 years hence and death. CONCLUSIONS: The SPMSQ and OMC, although highly correlated, are not equivalent. Association with race and education are greater for the OMC, whereas an association with age exists for both measures. The milder level of impairment identified by the OMC increases predictive capacity.