Relationship of homocysteine levels to quadriceps strength, gait speed, and late-life disability in older adults

BACKGROUND: Elevated homocysteine, causing tissue injury by such mechanisms as oxidative stress, endothelial damage, and protein homocysteinylation, is associated with multiple age-related problems including cardiovascular diseases, dementia, and osteoporotic fracture. Disability is one of the most common features in older adults. However, little is known about the role of homocysteine in physical disability among older adults. METHODS: Participants (>60 years, N = 1677) were from the National Health and Nutrition Examination Survey (NHANES) 1999-2002. Nineteen questionnaires in five major domains were administered to assess the level of difficulty in performing various tasks: activities of daily living (ADL), instrumental ADL (IADL), leisure and social activities (LSA), lower extremity mobility (LEM), and general physical activities (GPA). Peak quadriceps strength was obtained by using an isokinetic dynamometer. Habitual gait speed was obtained from a 20-foot timed walk. Homocysteine levels were measured by the Abbott homocysteine assay, an automated fluorescence polarization immunoassay (FPIA). RESULTS: Elevated homocysteine was associated with disability in ADL, IADL, LSA, and GPA after multivariate adjustment. The odds ratios (ORs) for disability in these domains comparing participants in the highest quartile of homocysteine to those in the lowest were 2.18 (95% confidence interval [CI], 1.32-3.59) for ADL; 1.62 (95% CI, 1.02-2.57) for IADL; 2.00 (95% CI, 1.14-3.51) for LSA; and 1.52 (95% CI, 1.05-2.21) for GPA. The strength of associations weakened somewhat after additional adjustment of quadriceps strength and/or gait speed, suggesting a mediating role of quadriceps strength and gait speed in the association between homocysteine and disability. Homocysteine had an inverse relationship to quadriceps strength and gait speed. Likewise, quadriceps strength seemed to mediate the inverse association between homocysteine and gait speed. CONCLUSIONS: Elevated homocysteine is associated with multiple domains of disability mediated in part by muscle strength and gait speed. The results suggest that homocysteine levels may be important indicators of performance status in older adults.     

Geriatric Impairments and Disability: The Cardiovascular Health Study

OBJECTIVES: To determine the relative importance of geriatric impairments (in muscle strength, physical capacity, cognition, vision, hearing, and psychological status) and chronic diseases in predicting subsequent functional disability in longitudinal analyses. DESIGN: Longitudinal data from the Cardiovascular Health Study were analyzed. Multivariable Cox hazards regression modeling was used to analyze associations between time‐dependent predictors and onset of disability in activities of daily living (ADLs) and mobility. SETTING: Four communities across the United States (Sacramento County, CA; Washington County, MD; Forsyth County, NC; and Allegheny County, PA). PARTICIPANTS: Five thousand eight hundred eighty‐eight elderly persons. MEASUREMENTS: Data were collected annually through in‐person examinations. RESULTS: ADL disability developed in 15% of participants and mobility disability in 30%. A single multivariable model was developed that included demographics, marital status, body mass index, and number of impairments and diseases. The hazard ratios (HRs) of having one, two, and three or more geriatric impairments (vs none) for the outcome of ADL disability were 2.12 (95% confidence interval (CI)=1.63–2.75), 4.25 (95% CI=3.30–5.48), and 7.87 (95% CI=6.10–10.17), respectively, and for having one, two, and three or more chronic diseases were 1.75 (95% CI=1.41–2.19), 2.45 (95% CI=1.95–3.07), and 3.26 (95% CI=2.53–4.19), respectively. Similarly, the HRs of having one, two, and three or more impairments for the outcome of mobility disability were 1.48 (95% CI=1.27–1.73), 2.08 (95% CI=1.77–2.45), and 3.70 (95% CI=3.09–4.42), respectively, and for having one, two, and three or more diseases were 2.06 (95% CI=1.76–2.40), 2.80 (95% CI=2.36–3.31), and 4.20 (95% CI=3.44–5.14), respectively. CONCLUSION: Number of geriatric impairments was more strongly associated than number of chronic diseases with subsequent ADL disability and nearly as strongly associated with the subsequent mobility disability.     

Health-protective and adverse effects of the apolipoprotein E epsilon2 allele in older men

OBJECTIVES: To reexamine a health‐protective role of the common apolipoprotein E (APOE) polymorphism focusing on connections between the APOE?2—containing genotypes and impairments in instrumental activities of daily living (IADLs) in older (≥65) men and women and to examine how diagnosed coronary heart disease (CHD), Alzheimer's disease, colorectal cancer, macular degeneration, and atherosclerosis may mediate these connections. DESIGN: Retrospective cross‐sectional study. SETTING: The unique disability‐focused data from a genetic subsample of the 1999 National Long Term Care Survey linked with Medicare service use files. PARTICIPANTS: One thousand seven hundred thirty‐three genotyped individuals interviewed regarding IADL disabilities. MEASUREMENTS: Indicators of IADL impairments, five geriatric disorders, and ?2‐containing genotypes. RESULTS: The ?2/3 genotype is a major contributor to adverse associations between the ?2 allele and IADL disability in men (odds ratio (OR)=3.09, 95% confidence interval (CI)=1.53–6.26), although it provides significant protective effects for CHD (OR=0.55, 95% CI=0.33–0.92), whereas CHD is adversely associated with IADL disability (OR=2.18, 95% CI=1.28–3.72). Adjustment for five diseases does not significantly alter the adverse association between ?2‐containing genotypes and disability. Protective effects of the ?2/3 genotype for CHD (OR=0.52, 95% CI=0.27–0.99) and deleterious effects for IADLs (OR=3.50, 95% CI=1.71–7.14) for men hold in multivariate models with both these factors included. No significant associations between the ?2‐containing genotypes and IADL are found in women. CONCLUSION: The ?2 allele can play a dual role in men, protecting them against some health disorders, while promoting others. Strong adverse relationships with disability suggest that ?2‐containing genotypes can be unfavorable factors for the health and well‐being of aging men.     

Linking C-reactive protein to late-life disability in the National Health and Nutrition Examination Survey (NHANES) 1999-2002

BACKGROUND: Chronic inflammation, measured by interleukin-6, predicts incident disability among elderly people. However, little is known about the relation of C-reactive protein (CRP) to disability. METHOD: Participants (>60 years old, N = 1680) were from the National Health and Nutrition Examination Survey 1999-2002. Disability in activities of daily living (ADL), instrumental activities of daily living (IADL), leisure and social activities (LSA), lower extremity mobility (LEM), and general physical activities (GPA) was obtained by self-report. Peak muscle power was the product of isokinetic peak leg torque and peak force velocity. Functional limitations were evaluated via habitual walking speed, which was obtained from a 20-foot timed walk. CRP levels were quantified by using latex-enhanced nephelometry. RESULTS: Elevated CRP levels were associated with disability in IADL, LSA, LEM, and GPA, independent of basic demographics, chronic medical diseases, health behaviors, as well as nutritional markers. The corresponding odds ratios of disability for each standard-deviation increase in natural-log-transformed CRP were 1.18 (95% confidence interval [CI], 1.02-1.35), 1.18 (95% CI, 1.00-1.39), 1.17 (95% CI, 1.03-1.33), and 1.17 (95% CI, 1.05-1.31), respectively. The relationship diminished after additional adjustment of leg power and/or walking speed, meaning that impairment in leg power and limitations in gait speed likely mediate the association between CRP and disability. CRP had an inverse relationship to leg power and walking speed. Likewise, additional adjustment for leg power substantially diminished the association between CRP and walking speed, suggesting a mediating effect of power between CRP and gait speed. CONCLUSIONS: Independent of chronic diseases, elevated CRP is associated with multiple domains of disability through mediation of muscle power, habitual gait speed, or both. Future research is needed to understand CRP as a risk factor for disability in older populations.     

Chronic inflammation, albuminuria, and functional disability in older adults with cardiovascular disease: the National Health and Nutrition Examination Survey, 1999-2008

ObjectiveAlthough C-reactive protein (CRP) and albuminuria are well-documented cardiovascular risk markers, the functional implications of these biomarkers and their combination on functional disability and metabolic risks in patients with cardiovascular disease (CVD) are unknown.MethodsData were from 1403 adults (≥60 years, mean 73.2 years) with CVD, ascertained by self-reported diagnosis of angina, coronary heart disease, congestive heart failure, myocardial infarction or stroke, in the National Health and Nutrition Examination Survey 1999–2008. Disability in activities of daily living (ADL), instrumental activities of daily living (IADL), leisure and social activities (LSA), general physical activities (GPA), and lower-extremity mobility (LEM) were obtained from self-reports. The urinary albumin-to-creatinine ratio (UACR) was calculated by dividing the urinary albumin value by the urinary creatinine concentration. CRP levels were quantified by latex-enhanced nephelometry.ResultsInflammation and albuminuria were associated with disability. In the full-adjusted models, odds ratios (ORs) (95% confidence intervals [CIs]) of disability in ADL, LSA, and LEM were 1.60 (1.13–2.28), 1.76 (1.22–2.55) and 2.31 (1.62–3.31), respectively, comparing participants in the highest CRP quartile to the lowest (p values for trend across CRP quartiles < 0.01). The corresponding ORs (95% CI) for disability in ADL, IADL, LSA, and LEM were 1.71 (1.20–2.45), 1.72 (1.21–2.45), 1.46 (1.01–2.12) and 2.50 (1.73–3.62), respectively, comparing participants in the highest UACR quartile to the lowest. We found combined association of inflammation and albuminuria with disability and with metabolic risks. Based on medians of both UACR and CRP, subjects with both higher levels of both markers had higher odds of disability and a more unfavorable metabolic profile than those with lower levels.ConclusionsElevated levels of CRP and UACR independently correlate with disability among older adults with CVD. There is a combined association of inflammation and albuminuria on multiple domains of disability and metabolic risks, suggesting the presence of elevated UACR may amplify the association of inflammation with disability and with metabolic risk in older adults living with CVD.     

Association of urgency symptoms with self-rated health, mood and functioning in an older population

BACKGROUND AND AIMS: Lower urinary tract symptoms (LUTS) with comorbidities are common in old age. The aim here was to investigate the associations of urgency symptoms with self-rated health, mood and functioning in a random older population adjusted for comorbid conditions. METHODS: A population-based cross-sectional survey was made involving 343 people (159 men and 184 women) aged 70 years and over. LUTS were categorized as symptoms with or without urgency. Perceived inconvenience from LUTS, self-rated health, mood, social activity and activities of daily living (ADL), instrumental activities of daily living (IADL) and mobility disability were the outcome measures. Ageand gender-adjusted and multivariate logistic regression models were constructed in order to examine the associations of urgency and non-urgency symptoms with the outcomes. The covariates were age, gender, and self-reported cardiovascular, musculoskeletal, neurological and other chronic diseases. RESULTS: Perceived inconvenience from urgency symptoms was more frequent than that from non-urgency symptoms (64% vs 20%, p<0.001). In the age- and gender-adjusted logistic regression models, LUTS with urgency were associated with poor self-rated health (OR [odds ratio] 2.35; 95% CI [confidence interval] 1.06-5.20), depressive mood (OR 7.29; 95% CI 2.91-18.30), ADL (OR 2.33; 95% CI 1.10-4.92), IADL (OR 2.16; 95% CI 1.19-3.92) and mobility disability (OR 2.44; 95% CI 1.37-4.36). LUTS without urgency were associated with depressive mood (OR 5.02; 95% CI 1.97-12.82) and mobility disability (OR 1.97; 95% CI 1.10-3.53). In the multivariate analyses in which comorbid conditions were added to the model, the associations of non-urgency and urgency symptoms persisted only with depressive mood (OR 4.00; 95% CI 1.52-10.53 and OR 6.16; 95% CI 2.39-15.84, respectively). CONCLUSION: Urgency symptoms are associated with poor self-rated health, depressive mood and disability in older people. There is an independent association between both urgency and non-urgency LUTS and depressive mood. A careful assessment of the mental state of older individuals with LUTS is warranted.     

Dementia as a predictor of functional disability: a four-year follow-up study

BACKGROUND: Prospective studies have shown that cognitive impairment is a strong and consistent risk factor of physical disability. However, cognitive impairment has been based on the result of a single screening tool. OBJECTIVE: To investigate the role of cognition in the subsequent incidence and decline of functional disability in basic activities of daily living (ADL) and instrumental activities of daily living (IADL) after a full assessment of dementia. METHODS: A group of 1,358 Japanese atomic bomb survivors aged 61 years or older who lived in the community or in institutions in Hiroshima City were followed for 4 years. During the baseline survey (1993-1995), subjects were administered a screening test for cognitive impairment. Those suspected of dementia underwent a series of cognitive tests (Hasegawa's dementia scale, Clinical Dementia Rating) and a neurological examination. The diagnosis of dementia was made according to DSM-III-R criteria. Study subjects were questioned about their reported ADL and their IADL. During the follow-up period, deaths were recorded and a follow-up survey (1997-1999) used to assess ADL and IADL performance. RESULTS: Dementia, even after adjustment for age, sex and history of stroke, was a strong predictor of functional disability, as indicated by ADL (odds ratio, OR = 14.0; confidence interval, CI = 5.4-36.3), IADL (OR = 10.1, CI = 2.2-46.4), and also by assessment of decline in ADL (OR = 9.8, CI = 4.2-22.8) or IADL status (OR = 3.9, CI = 1.8-8.3). CONCLUSION: Dementia is an important determinant of functional status. Deterioration in ADL is more significant than deterioration in IADL, suggesting that factors other than cognition, such as motivation or perceptual, sensory and motor abilities, may be important in IADL performance. This study confirms previous findings on risk factors that affect functional ability and extends our knowledge by examining several criteria of function that are important in the daily lives of elderly people.     

Cognitive function, habitual gait speed, and late-life disability in the National Health and Nutrition Examination Survey (NHANES) 1999-2002

BACKGROUND: Both cognitive function and gait speed are important correlates of disability. However, little is known about the combined effect of cognitive function and gait speed on multiple domains of disability as well as about the role of gait speed in the association between cognitive function and late-life disability. OBJECTIVE: To investigate (1) how cognition and habitual gait speed are related to late-life disability; (2) the role of habitual gait speed in the cognitiondisability association; and (3) the combined effect of cognitive function and habitual gait speed on late-life disability. METHOD: Participants (>60 years, n = 2,481) were from the National Health and Nutrition Examination Survey 1999-2002. Disability in activities of daily living (ADL), instrumental ADL (IADL), leisure and social activities (LSA), and lower extremity mobility (LEM) was obtained by self-report. Cognitive function was measured by a 2-min timed Digit Symbol Substitution Test (DSST), an executive function measure from the Wechsler Adult Intelligence Test. Habitual gait speed was obtained from a 20-foot timed walk. Multiple logistic regression was used to assess the association between cognitive function and disability. RESULTS: Cognitive function was associated with decreased likelihood for disability in each domain. The odds ratios (ORs) for disability in ADL, IADL, LSA, and LEM for each standard deviation (SD) increase in the DSST score were 0.47 (95% confidence interval [CI] = 0.34-0.64), 0.53 (95% CI = 0.42-0.67), 0.61 (95% CI = 0.47-0.79), and 0.73 (95% CI = 0.61-0.86), respectively, in the multi-variable models. After additional adjustment for habitual gait speed in the cognition-disability relationship, DSST score was no longer a significant correlate for LSA and LEM disability. The strength of the association between DSST score and disability in ADL/IADL was also diminished. The attenuated association between cognition and disability implies that limitation in gait speed likely mediates the association between cognitive function and disability. We found additive effects of cognition and habitual gait speed on late-life disability. The OR of disability in respective domains were lowest among participants with high-DSST score (high executive function) and with high gait speed. In contrast, the OR tended to be highest among participants with low-DSST score (low executive function) and low gait speed. CONCLUSION: Cognitive function was associated with multiple domains of disability. There was a joint effect of cognitive function and gait speed on late-life disability. This study also suggested that habitual gait speed partially mediated the inverse association between cognitive function and late-life disability, providing a mechanistic explanation in the context of disablement process.     

The combined effect of visual impairment and cognitive impairment on disability in older people

OBJECTIVES: To determine the risk of disability in individuals with coexisting visual and cognitive impairment and to compare the magnitude of risk associated with visual impairment, cognitive impairment, or the multimorbidity. DESIGN: Prospective cohort. SETTING: North Carolina. PARTICIPANTS: Three thousand eight hundred seventy-eight participants in the North Carolina Established Populations for the Epidemiologic Studies of the Elderly with nonmissing visual status, cognitive status, and disability status data at baseline MEASUREMENTS: Short Portable Mental Status Questionnaire (cognitive impairment defined as > or =4 errors), self reported visual acuity (visual impairment defined as inability to see well enough to recognize a friend across the street or to read newspaper print), demographic and health-related variables, disability status (activities of daily living (ADLs), instrumental activities of daily living (IADLs), mobility), death, and time to nursing home placement. RESULTS: Participants with coexisting visual and cognitive impairment were at greater risk of IADL disability (odds ratio (OR)=6.50, 95% confidence interval (CI)=4.34-9.75), mobility disability (OR=4.04, 95% CI=2.49-6.54), ADL disability (OR=2.84, 95% CI=1.87-4.32), and incident ADL disability (OR=3.66, 95%, CI=2.36-5.65). In each case, the estimated OR associated with the multimorbidity was greater than the estimated OR associated with visual or cognitive impairment alone, a pattern that was not observed for other adverse outcomes assessed. No significant interactions were observed between cognitive impairment and visual impairment as predictors of disability status. CONCLUSION: Individuals with coexisting visual impairment and cognitive impairment are at high risk of disability, with each condition contributing additively to disability risk. Further study is needed to improve functional trajectories in patients with this prevalent multimorbidity. When visual or cognitive impairment is present, efforts to maximize the other function may be beneficial.     

Chronic medical conditions as predictors of functional disability in an older population in Taiwan

Objective: As there is little understanding of disability processes in Taiwanese elders, the present study aimed to identify medical predictors of the incidence of activities of daily living (ADL) disability. Method: A total of 903 subjects were studied over a 4‐year period (1994–1998). The measurement instrument was the Chinese‐version Multidimensional Functional Assessment Questionnaire (CMFAQ). Only the subjects free of ADL disability at baseline were included in separate logistic regression models to predict disability in physical and instrumental ADL. Results: The hypothesised associations between chronic conditions and future functional disability were cross‐nationally confirmed. Arthritis, diabetes and hypertension were significantly predictive of the onset of physical ADL (PADL) disability; diabetes was the only medical predictor of instrumental ADL (IADL) disability. Age and educational level were significant predictors of PADL and IADL. Conclusions: Prevention programs for chronic disease need to pay more attention not only to the disabled population, but also to secondary prevention among those elders who have higher medical risk of developing disability.     

Depressive symptoms, chronic diseases, and physical disabilities as predictors of cognitive functioning trajectories in older Americans

OBJECTIVES: To determine the concurrent influence of depressive symptoms, medical conditions, and disabilities in activities of daily living (ADLs) on rates of decline in cognitive function of older Americans. DESIGN: Prospective cohort. SETTING: National population based. PARTICIPANTS: A national sample of 6,476 adults born before 1924. MEASUREMENTS: Differences in cognitive function trajectories were determined according to prevalence and incidence of depressive symptoms, chronic diseases, and ADL disabilities. Cognitive performance was tested five times between 1993 and 2002 using a multifaceted inventory examined as a global measure (range 0–35, standard deviation (SD) 6.0) and word recall (range 0–20, SD 3.8) analyzed separately. RESULTS: Baseline prevalence of depressive symptoms, stroke, and ADL limitations were independently and strongly associated with lower baseline cognition scores but did not predict future cognitive decline. Each incident depressive symptom was independently associated with a 0.06‐point lower (95% confidence interval (CI)=0.02–0.10) recall score, incident stroke with a 0.59‐point lower total score (95% CI=0.20–0.98), each new basic ADL limitation with a 0.07‐point lower recall score (95% CI=0.01–0.14) and a 0.16‐point lower total score (95% CI=0.07–0.25), and each incident instrumental ADL limitation with a 0.20‐point lower recall score (95% CI=0.10–0.30) and a 0.52‐point lower total score (95% CI=0.37–0.67). CONCLUSION: Prevalent and incident depressive symptoms, stroke, and ADL disabilities contribute independently to poorer cognitive functioning in older Americans but do not appear to influence rates of future cognitive decline. Prevention, early identification, and aggressive treatment of these conditions may ameliorate the burdens of cognitive impairment.     

ADL/ IADL dependencies and unmet healthcare needs in older persons: A nationwide survey

Purpose: To determine the impact of overall and component-wise activities for daily living (ADL) as well as instrumental activities of daily living (IADL) dependencies on unmet healthcare needs in older adults.Materials and Methods: Cross-sectional analyses were performed based on a National Survey of Older Koreans. A total of 10,082 participants aged ≥ 65 years were included. All data were collected through standardized, personal interviews with participants and their representatives. Logistic regression was used to analyse the risk of unmet healthcare needs, with or without adjustment.Results: Amongst all participants, 734 (7.2%) had ADL dependency. Participants with ADL dependency had lower income, education level, and perceived health status (p<0.001). The adjusted odds ratio (aOR) for the risk of unmet healthcare needs was 1.52 (95%, confidence interval [CI] 1.19–1.95) for ADL and 1.54 (95%, CI 1.28–1.86) for IADL. When men have ADL dependency, aOR of unmet healthcare needs was higher than that of women (aOR 1.89, 95% CI 1.15 - 3.11; aOR 1.65, 95% CI 1.15 - 2.36, respectively) and IADL showed the same trend. Any dependency on ADL or IADL was associated with higher risk of unmet healthcare needs, whether adjusted or not (p<0.001).Conclusions: Older adults with ADL or IADL dependency had higher risks of unmet healthcare needs than their independent counterparts. In addition to mobility problems, other components were related to unmet healthcare needs. Therefore, to reduce unmet healthcare needs, integration of health and social care that supports ADL or IADL dependency should be considered.     

Prediction of functional disability by depressive state among community‐dwelling elderly in Japan: A prospective cohort study

Aim: We carried out a prospective cohort study to evaluate the risk factors of functional disability by depressive state. Methods: A total of 783 men and women, aged 70 years and over, participated in this study. We followed the participants in terms of the onset of functional disability by using a public long‐term care insurance database. The Geriatric Depression Scale (GDS) was used to measure depressive state. Age, sex, history of chronic disease, living alone, fall experience, cognitive impairment, instrumental activities of daily living (IADL), the Motor Fitness Scale (MFS), frequency of going out and social support at baseline were used as the main covariates. The Cox regression analysis was used to examine the difference in functional disability stratified according to depressive state. Results: The incidence of functional disability was 38 persons in the non‐depression group and 42 persons in the depression group (RR 2.34; 95% CI 1.46–3.79). The results of the depression group showed a significant difference in cognitive impairment (HR 3.51; 95% CI 1.39–8.85), MFS (HR 5.60; 95% CI 1.32–23.81) and IADL (HR 3.37; 95% CI 1.65–6.85). The results of the non‐depression group showed a significant difference in MFS (HR 2.97; 95% CI 1.47–6.96), and frequency of going out (HR 3.21; 95% CI 1.47–6.96). Conclusions: In conclusion, risk factors for functional disability were found to differ on the basis of whether or not community‐dwelling elderly individuals experience depressive state. The type of support offered must be based on whether or not depressive state is present. Geriatr Gerontol Int 2012; ??: ??–?? .     

Effects of provider practice on functional independence in older adults

OBJECTIVES: To examine provider determinants of new-onset disability in basic activities of daily living (ADLs) in community-dwelling elderly. DESIGN: Observational study. SETTING: King County, Washington. PARTICIPANTS: A random sample of 800 health maintenance organization (HMO) enrollees aged 65 and older participating in a prospective longitudinal cohort study of dementia and normal aging and their 56 primary care providers formed the study population. MEASUREMENTS: Incident ADL disability, defined as any new onset of difficulty performing any of the basic ADLs at follow-up assessments, was examined in relation to provider characteristics and practice style using logistic regression and adjusting for case-mix, patient and provider factors associated with ADL disability, and clustering by provider. RESULTS: Neither provider experience taking care of large numbers of elderly patients nor having a certificate of added qualifications in geriatrics was associated with patient ADL disability at 2 or 4 years of follow-up (adjusted odds ratio (AOR) for experience=1.29, 95% confidence interval (CI)=0.81-2.05; AOR for added qualifications=0.72, 95% CI=0.38-1.39; results at 4 years analogous). A practice style embodying traditional geriatric principles of care was not associated with a reduced likelihood of ADL disability over 4 years of follow-up (AOR for prescribing no high-risk medications=0.56, 95% CI=0.16-1.94; AOR for managing geriatric syndromes=0.94, 95% CI=0.40-2.19; AOR for a team care approach=1.35, 95% CI=0.66-2.75). CONCLUSION: Taking care of a large number of elderly patients, obtaining a certificate of added qualifications in geriatrics, and practicing with a traditional geriatric orientation do not appear to influence the development of ADL disability in elder, community dwelling HMO enrollees.     

Clinical Diagnosis and Disability Among Community Dwellers Aged 75 and Over: The Sydney Older Persons Study

Objectives : Disability is an important predictor of health and community service utilisation. Understanding its pathogenesis has implications for planning of future health services. The aim of our study was to examine the contribution of systemic, psychiatric and neurodegenerative diseases to disability in an “old‐old” population. Methods : 647 men and women over the age of 75 participated in the Sydney Older Person's Study. Disability in activities of daily living (ADL), instrumental activities of daily living (IADL) and mobility was assessed using self report, informant and clinician assessments. Diagnoses of systemic, psychiatric, neurodegenerative diseases were made by clinicians. Individual disease contribution to disability was assessed using multiple regression analysis. Contribution to disability by the groups of systemic, neurodegenerative and psychiatric diagnoses was assessed, using hierarchical regression. Results : Neurodegenerative diseases were the major contributors to ADL impairment. Systemic and psychiatric diseases played a role in IADL and mobility impairment, as did the neurodegenerative diseases. Of the neurodegenerative diseases, dementia/cognitive impairment and Parkinsonism/gait slowing particularly contributed to disability. Self‐report under‐identified the role of the neurodegenerative diseases in disability. It also introduced a gender effect, that the clinical measures did not share to the same extent. Conclusions : Neurodegenerative diseases are important contributors to disability and assessments and diagnosis of neurodegenerative diseases should be included in disability assessments. Self report under‐identifies the importance of these conditions.     

The relation of peripheral arterial disease to leg force, gait speed, and functional dependence among older adults

BACKGROUND: Atherosclerotic peripheral arterial disease (PAD), common among older adults, is associated with poor low-extremity functioning. In considering functional status, varying domains exist, including activities of daily living (ADL), instrumental activities of daily living (IADL), low-extremity mobility (LEM), and leisure and/or social activities (LSA). However, little is known about how PAD is related to functional status beyond low-extremity functioning. METHODS: A total of 1798 participants 60 years old or older was selected from the population-based National Health and Nutrition Examination Survey 1999-2002 in the United States. ADL, IADL, LSA, LEM, and general physical activities (GPA) were obtained by self-report. Peak leg force was obtained from an isokinetic dynamometer. Habitual gait speed was obtained from a 20-foot timed walk. PAD was defined as an ankle-brachial blood pressure index <0.9 in either leg. RESULTS: After multivariable adjustment, the odds ratios (ORs) for dependence in IADL, LSA, and LEM comparing participants with PAD to those without were 1.60 (95% confidence interval [CI], 1.11-2.29), 1.63 (95% CI, 1.08-2.44), and 2.29 (95% CI, 1.64-3.18), respectively. Additional adjustment of peak leg force and/or habitual gait speed diminished the relations of PAD to dependence in IADL and LSA. PAD was associated with an 18.06 Newton reduction (p =.003) in peak leg force and a 0.05 m/s reduction (p =.002) in habitual gait speed. CONCLUSION: PAD was independently associated with multiple domains of functional dependence. The association between PAD and dependence in IADL and LSA was to a large extent mediated by leg force and gait speed.     

Incident physical disability in people with lower extremity peripheral arterial disease: the role of cardiovascular disease

OBJECTIVES: To evaluate the risk of incident physical disability and the decline in gait speed over a 6-year follow-up associated with a low ankle-arm index (AAI) in older adults.
DESIGN: Observational cohort study.
SETTING: Forsyth County, North Carolina; Sacramento County, California; Washington County, Maryland; and Allegheny County, Pennsylvania.
PARTICIPANTS: Four thousand seven hundred five older adults, 58% women and 17.6% black, participating in the Cardiovascular Health Study.
MEASUREMENTS: AAI was measured in 1992/93 (baseline). Self-reported mobility, activity of daily living (ADL), and instrumental activity of daily living (IADL) disability and gait speed were recorded at baseline and at 1-year intervals over 6 years of follow-up. Mobility disability was defined as any difficulty walking half a mile and ADL and IADL disability was defined as any difficulty with 11 specific ADL and IADL tasks. Individuals with mobility, ADL, or IADL disability at baseline were excluded from the respective incident disability analyses.
RESULTS: Lower baseline AAI values were associated with increased risk of mobility disability and ADL/IADL disability. Clinical cardiovascular disease (CVD), diabetes mellitus, and interim CVD events partially explained these associations for mobility disability and clinical CVD and diabetes mellitus partially explained these associations for ADL and IADL disability. Individuals with an AAI less than 0.9 had on average a mean decrease in gait speed of 0.02 m/s per year, or a decline of 0.12 m/s over the 6-year follow-up. Prevalent CVD partly explained this decrease but interim CVD events did not further attenuate it.
CONCLUSION: Low AAI serves as marker of future disability risk. Reduction of disability risk in patients with a low AAI should consider cardiovascular comorbidity and the prevention of additional disabling CVD events.     

Disability transitions in the oldest old in the general population. The Leiden 85-plus study

Transitions between disability states in older people occur frequently. This study investigated predictors of disability transitions in the oldest old and was performed in the Leiden 85-plus study, a population-based prospective cohort study among 597 participants aged 85 years. At baseline (age 85 years), data on sociodemographic characteristics and chronic diseases were obtained. Disabilities in basic activities of daily living (BADL) and instrumental activities of daily living (IADL) were measured annually for 5 years with the Groningen Activities Restriction Scale (GARS). Mortality data were obtained. A statistical multi-state model was used to assess the risks of transitions between no disabilities, IADL disability, BADL disability, and death. At baseline, 299 participants (50.0 %) were disabled in IADL only, and 155 participants (26.0 %) were disabled in both BADL and IADL. During 5-year follow-up, 374 participants (62.6 %) made >1 transition between disability states, mostly deterioration in disability. Males had a lower risk of deterioration [hazard ratio (HR), 0.75 (95 % CI, 0.58–0.96)] compared to females. No gender differences were observed for improvement [HR, 0.64 (95 % CI, 0.37–1.11)]. Participants with depressive symptoms were less likely to improve [HR, 0.50 (95 % CI, 0.28–0.87)]. Participants with depressive symptoms [HR, 1.46 (95 % CI, 1.12–1.91)], >1 chronic disease [HR, 1.60 (95 % CI, 1.27–2.01)], and with cognitive impairment [HR, 1.60 (95 % CI, 1.20–2.13)] had the highest risk of deteriorating. Disability is a dynamic process in the oldest old. Deterioration is more common than improvement. Older men are less likely to deteriorate than women. The presence of depressive symptoms, chronic disease, and cognitive impairment predicts deterioration.     

Pulmonary Function and Cognitive Decline in an Older Chinese Population in Singapore

Abstract

Introduction: Various cognitive deficits associated with reduced pulmonary function are reported in different studies, but the pattern of cognitive deficits across multiple domains and its associated everyday functional disability remain unclear. Methods: We analyzed neuropsychological functioning, cognitive impairment and accompanying disability in instrumental activities of daily living (IADL) associated with reduced pulmonary function in community-living middle-aged and older adults in Singapore. Performance on a comprehensive battery of neuropsychological tests, spirometry and cognitively demanding IADLs were assessed in the population-based Singapore Longitudinal Ageing Studies. Results: Consecutive 10% increase in forced expiratory volume in 1 s (FEV1) as percent of predicted was positively associated with 0.18 points increase in Mini-mental state examination (MMSE) and 0.04 points increase in executive function, independent of age, education and other variables. Subjects with moderate-to-severe airway obstruction showed significantly poorer MMSE score (p for linear trend = 0.001), and information processing speed (p for linear trend < 0.001). FEV1 (per 10% of predicted) was significantly associated with lower risk of cognitive impairment (OR = 0.92, 95% CI: 0.87-0.98, P = 0.005) and cognitive IADL disability (OR = 0.86,95% CI:0.79–0.93, P < 0.001). Pulmonary restriction was associated with greater risk of cognitive impairment (OR = 1.98, 95% CI: 1.26-3.11, P = 0.003) and cognitive IADL disability (OR = 2.43, 95% CI: 1.31-4.53, P = 0.005). Moderate-to-severe airway obstruction (OR = 2.04, 95% CI: 1.11–3.74, P = 0.022) was positively associated with cognitive IADL disability. Conclusion: The findings suggest a measurable but modest cognitive effect of low pulmonary function that was accompanied by corresponding disability in living activities. The effect on executive functioning should be further investigated in longitudinal studies.     

Abdominal fat distribution and functional limitations and disability in a biracial cohort: the Atherosclerosis Risk in Communities Study

OBJECTIVE: To examine the associations of abdominal fat and obesity with functional limitations and disability in late adulthood. DESIGN: Longitudinal, cohort study. PARTICIPANTS: African American and white men and women aged 45-64 y at baseline with measured waist circumference, waist-to-hip ratio (WHR), and body mass index (BMI) who participated in the Atherosclerosis Risk in Communities (ARIC) Study (n = 9416). OUTCOME MEASURES: Self-reported functional limitations, activities of daily living (ADLs), and instrumental activities of daily living (IADLs) at ages 52-75 y. RESULTS: Waist circumference, WHR, and BMI were positively associated with functional limitations and ADL and IADL impairment approximately 9 y later among African American and white men and women. For example, in African American women the odds ratios (95% CI) associated with a one standard deviation (s.d.) increment in waist circumference (13.3 cm) for severe functional limitations and ADL and IADL impairment were 2.36 (2.00-2.79), 1.41 (1.25-1.58), and 1.49 (1.34-1.66), respectively. In white women, the odds ratios (95% CI) were 2.66 (2.39-2.96), 1.60 (1.47-1.74), and 1.42 (1.31-1.53), respectively. Similar associations were found in men. A 1 s.d. increment in WHR (0.08 U) and BMI (5.06 kg/m2) produced similar results. The associations of waist circumference and WHR with functional limitations and ADL and IADL impairment were attenuated but, in general, remained statistically significant when BMI was added to the models. CONCLUSIONS: Maintaining a healthy body weight and avoiding increases in abdominal fat should be investigated for their potential to reduce the risk of functional limitations and disability in an aging population.