Loneliness prevention and the role of the Public Health system.

AIMS: To evaluate evidence on loneliness interventions that have been assessed and found effective, both for remediation and addressing fundamental causes of loneliness; to consider why population-level primary prevention strategies targeting fundamental causes are necessary, and determine areas for future research; and to outline an integrated approach to prevention considering roles for the Public Health system. METHOD: We conducted a review of systematic reviews to identify effective loneliness interventions and classified them in our Population-Prevention Matrix according to public health impact, amount of individual effort required, and level of prevention. We also highlighted emerging interventions that have yet to be formally evaluated. RESULTS: We identified a range of preventive or therapeutic approaches, and a dearth of population-level primary prevention interventions targeting fundamental causes of loneliness. Filling this gap will be essential in addressing the loneliness epidemic, and we provided emerging examples of population-level primary prevention interventions that may inform future efforts. CONCLUSION: Based on evidence to date, we suggest an integrated approach to prevention with significant roles for the US Public Health system, including its function as Chief Health Strategist to lead and guide multisystem approaches to loneliness prevention, with a particular focus on population-level primary prevention strategies.

Allostatic load and frailty in the women's health and aging studies.

BACKGROUND: Frailty involves decrements in many physiologic systems, is prevalent in older ages, and is characterized by increased vulnerability to disability and mortality. It is yet unclear how this geriatric syndrome relates to a preclinical cumulative marker of multisystem dysregulation. The purpose of this study was to evaluate whether allostatic load (AL) was associated with the geriatric syndrome of frailty in older community-dwelling women. METHODS: We examined the cross-sectional relationship between AL and a validated measure of frailty in the baseline examination of two complementary population-based cohort studies, the Women's Health and Aging studies (WHAS) I and II. This sample of 728 women had an age range of 70-79. We used ordinal logistic regression to estimate the relationship between AL and frailty controlling for covariates. RESULTS: About 10% of women were frail and 46% were prefrail. AL ranged from 0 to 8 with 91% of participants scoring between 0 and 4. Regression models showed that a unit increase in the AL score was associated with increasing levels of frailty (OR = 1.16, 95% CI = 1.04-1.28) controlling for race, age, education, smoking status, and comorbidities. CONCLUSION: This study suggests that frailty is associated with AL. The observed relationship provides some support for the hypothesis that accumulation of physiological dysregulation may be related to the loss of reserve characterized by frailty.

Low serum carotenoids are associated with a decline in walking speed in older women.

BACKGROUND AND OBJECTIVES: Walking speed is an important measure of physical performance that is predictive of disability and mortality. The relationship of dietary factors to changes in physical performance has not been well characterized in older adults. The aim was to determine whether total serum carotenoid concentrations, a marker for fruit and vegetable intake, and serum selenium are related to changes in walking speed in older women. SUBJECTS AND METHODS: The relationship between total serum carotenoids and selenium measured at baseline, 12, and 24 months follow-up and walking speed assessed at baseline and every six months for 36 months was examined in 687 moderately to severely disabled women, 65 years or older, living in the community. RESULTS: Mean total serum carotenoids were associated with mean walking speed over three years of follow-up (P = 0.0003) and rate of change of walking speed (P = 0.007) in multivariate linear regression models adjusting for age, body mass index, and chronic diseases. Mean serum selenium was associated with mean walking speed over three years of follow-up (P = 0.0003) but not with the rate of change of walking speed (P = 0.26). CONCLUSIONS: These findings suggest that a higher fruit and vegetable intake, as indicated by higher total serum carotenoid concentrations, may be protective against a decline in walking speed in older women.

Relationship of Physical Frailty to Phosphocreatine Recovery in Muscle after Mild Exercise Stress in the Oldest-Old Women.

BACKGROUND: Physical frailty is a clinical syndrome associated with aging and manifesting as slowness, weakness, reduced physical activity, weight loss, and/or exhaustion. Frail older adults often report that their major problem is "low energy", and there is indirect evidence to support the hypothesis that frailty is a syndrome of dysregulated energetics. We hypothesized that altered cellular energy production underlies compromised response to stressors in the frail. METHODS: We conducted a pilot study to assess muscle energetics in response to a mild isometric exercise challenge in women (n=30) ages 84-93 years. The frailty status was assessed by a validated physical frailty instrument. Localized phosphorus (P31) magnetic resonance spectroscopy with a 1.5T magnet was used to assess the kinetics of Phosphocreatine recovery in the tibialis anterior muscle following maximal isometric contraction for 30 seconds. RESULTS: Phosphocreatine recovery following exertion, age-adjusted, was slowest in the frail group (mean=189 sec; 95%CI: 150,228) compared to pre-frail (mean=152 sec; 95%CI: 107,197) and nonfrail subjects (mean=132 sec; 95%CI: 40,224). The pre-frail and frail groups had 20 sec (95%CI: -49,89) and 57 sec (95%CI: -31,147) slower phosphocreatine recovery, respectively, than the non-frail. This response was paralleled by dysregulation in glucose recovery in response to oral glucose tolerance test in women from the same study population. CONCLUSIONS: Impaired muscle energetics and energy metabolism might be implicated in the physical frailty syndrome.

Physical Frailty: ICFSR International Clinical Practice Guidelines for Identification and Management.

OBJECTIVE: The task force of the International Conference of Frailty and Sarcopenia Research (ICFSR) developed these clinical practice guidelines to overview the current evidence-base and to provide recommendations for the identification and management of frailty in older adults. METHODS: These recommendations were formed using the GRADE approach, which ranked the strength and certainty (quality) of the supporting evidence behind each recommendation. Where the evidence-base was limited or of low quality, Consensus Based Recommendations (CBRs) were formulated. The recommendations focus on the clinical and practical aspects of care for older people with frailty, and promote person-centred care. Recommendations for Screening and Assessment: The task force recommends that health practitioners case identify/screen all older adults for frailty using a validated instrument suitable for the specific setting or context (strong recommendation). Ideally, the screening instrument should exclude disability as part of the screening process. For individuals screened as positive for frailty, a more comprehensive clinical assessment should be performed to identify signs and underlying mechanisms of frailty (strong recommendation). Recommendations for Management: A comprehensive care plan for frailty should address polypharmacy (whether rational or nonrational), the management of sarcopenia, the treatable causes of weight loss, and the causes of exhaustion (depression, anaemia, hypotension, hypothyroidism, and B12 deficiency) (strong recommendation). All persons with frailty should receive social support as needed to address unmet needs and encourage adherence to a comprehensive care plan (strong recommendation). First-line therapy for the management of frailty should include a multi-component physical activity programme with a resistance-based training component (strong recommendation). Protein/caloric supplementation is recommended when weight loss or undernutrition are present (conditional recommendation). No recommendation was given for systematic additional therapies such as cognitive therapy, problem-solving therapy, vitamin D supplementation, and hormone-based treatment. Pharmacological treatment as presently available is not recommended therapy for the treatment of frailty.

Stimulus-response paradigm for characterizing the loss of resilience in homeostatic regulation associated with frailty.

Frailty is a state of health signified by an increased vulnerability to adverse health outcomes in the face of stressors (e.g. infection). There is emerging consensus that research on both the theory and measurement of frailty must focus on the dynamic interactions within and across systems underlying the frailty syndrome. In this paper, we propose a dynamical systems modeling approach, based on the stimulus-response experimental paradigm, to propel future advances in the study of frailty. Our proposal is novel in that it provides a quantitative framework to operationalize and test the core notion underlying frailty that it signifies a loss of resilience in homeostatic regulation. The proposed framework offers many important benefits, including (a) insights into whether and how homeostatic regulation differs between frail and non-frail older adults, (b) identification of critical regulatory systems, if they exist, that could function as sentinel systems for screening and early detection of frailty, (c) establishment of the value of provocative tests that can provide maximal information on the integrity of systems identified in (b), and (d) evaluation and unification of diverse empirical descriptions of frailty by providing a mathematical framework anchored in quantifying the loss of resilience, an essential property of frailty.

Markers of B-vitamin deficiency and frailty in older women.

OBJECTIVE: To evaluate the association between markers of vitamins B12, B6 and folate deficiency and the geriatric syndrome of frailty. DESIGN: Cross-sectional study of baseline measures from the combined Women's Health and Aging Studies. SETTING: Baltimore, Maryland. PARTICIPANTS: Seven hundred three community-dwelling women, aged 70-79. MEASUREMENTS: Frailty was defined by five-component screening criteria that include weight, grip strength, endurance, physical activity and walking speed measurements and modeled as binary and 3-level polytomous outcomes. Independent variables serum vitamin B6, vitamin B12, methylmalonic acid, total homocysteine, cystathionine and folate were modeled continuously and as abnormal versus normal. RESULTS: Serum biomarker levels varied significantly by race. All analyses were race-stratified and results are reported only for Caucasian women due to small African American sample size. In polytomous logistic regression models of 3-level frailty, Caucasian women with increasing MMA, defined either continuously or using a predefined threshold, had 40-60% greater odds of being prefrail (p-values < 0.07) and 1.66-2.33 times greater odds of being frail (p-values < 0.02) compared to nonfrails after adjustment for age, education, low serum carotenoids, alcohol intake, cardiovascular disease and renal impairment. Both binary and polytomous frailty models evaluating vitamin B12 as the main exposure estimated odds ratios that were similar in trend yet slightly less significant than the MMA results. CONCLUSIONS: These results suggest that vitamin B12 deficiency may contribute to the frailty syndrome in community-dwelling older women. Future studies are needed to explore these relationships longitudinally.

Soluble intracellular adhesion molecule-1 is associated with cardiovascular disease risk and mortality in older adults.

BACKGROUND: Intracellular adhesion molecule-1 (ICAM-1) regulates leukocyte-endothelial attachment, a process crucial to atherosclerosis. Circulating soluble ICAM-1 (sICAM-1) may serve as a marker of cardiovascular disease (CVD) progression. OBJECTIVES: We examined the association of sICAM-1 with measures of subclinical CVD and risk of incident CVD events and death in older men and women (age > or = 65 years) from the Cardiovascular Health Study. METHODS: Selected participants were free of clinical CVD at baseline. Non-exclusive incident case groups were angina (n = 534), myocardial infarction (n = 304), stroke (n = 327), and death (n = 842; CVD death = 310). A total 643 subjects were free of events during follow-up. RESULTS: sICAM-1 was positively associated with C-reactive protein, interleukin-6 and fibrinogen and measures of subclinical CVD in these older men and women. In Cox regression models adjusted for age, gender, and race, increasing levels of sICAM-1 were associated with increased risk of all cause mortality in men and women. Hazard ratios (95% confidence intervals) for a one standard deviation increase in sICAM-1 (89.7 ng mL(-1)) were 1.3 (1.1-1.4) in men and 1.2 (1.1-1.3) in women. sICAM-1 was associated with increased risk of CVD death in women (1.2; 1.0-1.5), but not men (1.1; 0.9-1.3). There were no associations of sICAM-1 with non-fatal CVD events. CONCLUSIONS: While sICAM-1 was associated with death in older men and women, there was a more marked association between sICAM-1 and CVD death in women.

A cross-sectional study of vitamin C and cognitive function in older adults: the differential effects of gender.

Previous studies have suggested that vitamin C status may be associated with cognitive function in community-dwelling populations. However, this has not been consistent across all studies due to methodological differences. This cross-sectional study assessed the association between vitamin C and cognitive function in 544 community-dwelling older adults aged 65 or older who participated in both the Cardiovascular Health Study (CHS) and the CLUE II study in 1989. Three percent of the subjects had low plasma vitamin C concentrations (< 40 mg/dL) and 15% had low total vitamin C intake (< 60 mg/day). Most participants (96.7 percent) had normal cognitive function. In the unadjusted analyses, the highest fifth of plasma vitamin C concentration was associated with better Digit Symbol Substitution Test (DSST) scores and marginally associated with Mini-Mental State Examination (MMSE) compared to the lowest fifth. Total vitamin C intake, measured by Block's food frequency questionnaire, was generally associated with higher MMSE scores, though it was not significant. Adjusting for numerous factors did not substantially change results. In a stratified analysis by gender, higher plasma concentrations or intake were associated with higher MMSE scores for men but not for women. These mixed results do not provide strong evidence of an association between vitamin C concentrations or intake and cognitive function.

Denture use, malnutrition, frailty, and mortality among older women living in the community.

BACKGROUND: The relationships between denture use, malnutrition, frailty, and mortality in older women have not been well characterized. OBJECTIVE: To determine whether women who use dentures and have difficulty chewing or swallowing are at higher risk of malnutrition, frailty, and mortality. DESIGN: Cross-sectional and longitudinal study of 826 women, aged 70-79, from the Women's Health and Aging Studies, two population-based longitudinal studies of community-dwelling women in Baltimore, Maryland. At enrollment, data on frailty and self-reported denture use and difficulty chewing or swallowing that limited the ability to eat was collected, and plasma vitamins A, D, E, B6, and B12, carotenoids, folate, and albumin were measured. RESULTS: 63.5% of women reported using dentures, of whom 11.6% reported difficulty chewing or swallowing food. Denture users with and without difficulty chewing or swallowing and those not using dentures had, respectively, geometric mean (95% Confidence Interval [C.I.]) total plasma carotenoid concentrations of 1.481 (1.302, 1.684), 1.616 (1.535, 1.700), and 1.840 (1.728, 1.958) micromol/L, respectively (P < 0.0001), and 25- hydroxyvitamin D of 50.90 (44.25, 58.55), 47.46 (45.15, 50.40), and 54.0 (50.9, 56.8) nmol/L (P < 0.0001). The proportion using dentures among non-frail, pre-frail, and frail women was 58%, 66%, and 73%, respectively (P = 0.018). Women who used dentures and reported difficulty chewing or swallowing had lower five-year survival (H.R. 1.43, 95% C.I. 1.05-1.97), after adjusting for potential confounders. CONCLUSIONS: Older women living in the community who use dentures and have difficulty chewing or swallowing have a higher risk of malnutrition, frailty, and mortality.

Cardiovascular disease, interleukin-6, and risk of mortality in older women: the women's health and aging study.

BACKGROUND: Systemic chronic inflammation has been found to be related to all-cause mortality risk in older persons. We investigated whether specific chronic conditions, particularly cardiovascular disease (CVD), affect the association between high interleukin (IL)-6 level and mortality in a sample of disabled older women. METHODS AND RESULTS: IL-6 serum level was measured at baseline in 620 women >/=65 years old. The presence and severity of medical conditions was ascertained by standard criteria that used multiple sources of information. The sample was surveyed over the 3-year follow-up. After adjustment for potential confounders, compared with those in the lowest tertile, women in the highest IL-6 tertile were at higher risk of all-cause mortality. The presence of CVD, however, strongly affected the risk of mortality associated with high IL-6. Among women with prevalent CVD, those with high IL-6 levels had >4-fold risk of death (RR 4.6; 95% CI 2.0 to 10.5) compared with women in the lowest tertile, whereas the relative risk associated with high IL-6 among those without CVD was much lower and not significant (RR 1.8; 95% CI 0.7 to 4.2). Adjustment for all chronic diseases and disease severity measures, including ankle-brachial index, forced expiratory volume, and exercise tolerance, did not change the results. CONCLUSIONS: IL-6 level is helpful in identifying a subgroup of older CVD patients with high risk of death over a period of 3 years. Systemic inflammation, as measured by IL-6, may be related to the clinical evolution of older patients with CVD.

IL-6 gene variation is not associated with increased serum levels of IL-6, muscle, weakness, or frailty in older women.

Elevated levels of the inflammatory cytokine IL-6 are associated with the development of disability, frailty, and mortality in older adults. These outcomes are likely mediated through inflammatory activity that alters hormones, skeletal muscle, and the immune system. Polymorphic variants in the IL-6 gene influence IL-6 expression. We hypothesized that IL-6 alleles associate with increased serum of IL-6, decreased muscle strength, and frailty, and tested this in the Women's Health and Aging cohorts. We genotyped 463 participants age 70-79, and identified three common IL-6 haplotype blocks for the Caucasian (n=363) and African American (n=100) subsets. Using linear and logistic regression, and adjusting for age, BMI, race, and osteoarthritis, we identified no significant or clinically meaningful relationship between any single IL-6 single nucleotide polymorphism (SNP) or any IL-6 haplotype and serum IL-6 level, grip, knee, or hip strength, or frailty. Given that the promoter SNP (rs1800795) has been reported to influence IL-6 levels and health outcomes, we performed a similar association study in the In Chianti population (n=266) and confirmed lack of association. These results suggest that IL-6 gene variation may not be an important factor in the determination of elevated IL-6 levels and related phenotypes found in older women.

Predicting the risk of mobility difficulty in older women with screening nomograms: the Women's Health and Aging Study II.

BACKGROUND: A major obstacle to screening for early mobility disability (ie, mobility difficulty), a major public health concern, is the lack of a method that identifies those who are at high risk. The goal of this study was to develop easy-to-use clinical nomograms for estimation of the probability of incident mobility difficulty. METHODS: We conducted a population-based prospective study using data from 266 high physically and cognitively functioning older women, aged 70 to 80 years, who were free of mobility disability at the baseline evaluation of the Women's Health and Aging Study II. The outcome measure was incident mobility disability within 18 months, defined as self-reported difficulty walking 0.8 km, climbing 10 steps, or transferring from or into a car or bus. Logistic regression and receiver operating characteristic curve analyses were used for evaluation of the optimal combination of self-reported and performance-based mobility measures. Bootstrap sampling and estimation was used for validation. RESULTS: Predictive nomograms were developed based on a final model that included 3 simple-to-obtain measures of preclinical disability: self-report of modification in mobility tasks without having difficulty with them, one-leg stance balance, and time to walk 1 m at a usual pace. Final model accuracy (as estimated by the area under the receiver operating characteristic curve) was 73% (SE = 0.04). Validation analysis confirmed the high accuracy of these nomograms. CONCLUSIONS: An original tool was developed for assessment of the risk of mobility difficulty in older women that can be used to assist physicians and researchers in deciding which women to target for preventive interventions.

Risk factors for falling in home-dwelling older women with stroke: the Women's Health and Aging Study.

BACKGROUND AND PURPOSE: Much of our knowledge of risk factors for falls comes from studies of the general population. The aim of this study was to estimate the risk of falling associated with commonly accepted and stroke-specific factors in a home-dwelling stroke population. METHODS: This study included an analysis of prospective fall reports in 124 women with confirmed stroke over 1 year. Variables relating to physical and mental health, history of falls, stroke symptoms, self-reported difficulties in activities of daily living, and physical performance tests were collected during home assessments. RESULTS: Risk factors for falling commonly reported in the general population, including performance tests of balance, incontinence, previous falls, and sedative/hypnotic medications, did not predict falls in multivariate analyses. Frequent balance problems while dressing were the strongest risk factor for falls (odds ratio, 7.0). Residual balance, dizziness, or spinning stroke symptoms were also a strong risk factor for falling (odds ratio, 5.2). Residual motor symptoms were not associated with an increased risk of falling. CONCLUSIONS: Interventions to reduce the frequency of balance problems during complex tasks may play a significant role in reducing falls in stroke. Clinicians should be aware of the increased risk of falling in women with residual balance, dizziness, or spinning stroke symptoms and recognize that risk assessments developed for use in the general population may not be appropriate for stroke patients.

Association of IGF-I levels with muscle strength and mobility in older women.

The functional consequences of the age-associated decline in IGF-I are unknown. We hypothesized that low IGF-I levels in older women would be associated with poor muscle strength and mobility. We assessed this question in a population representative of the full spectrum of health in the community, obtaining serum IGF-I levels from women aged 70-79 yr, enrolled in the Women's Health and Aging Study I or II. Cross-sectional analyses were performed using 617 women with IGF-I levels drawn within 90 d of measurement of outcomes. After adjustment for age, there was an association between IGF-I and knee extensor strength (P = 0.004), but not anthropometry or other strength measures. We found a positive relationship between IGF-I levels and walking speed for IGF-I levels below 50 microg/liter (P < 0.001), but no relationship above this threshold. A decline in IGF-I level was associated with self-reported difficulty in mobility tasks. All findings were attenuated after multivariate adjustment. In summary, in a study population including frail and healthy older women, low IGF-I levels were associated with poor knee extensor muscle strength, slow walking speed, and self-reported difficulty with mobility tasks. These findings suggest a role for IGF-I in disability as well as a potential target population for interventions to raise IGF-I levels.

Left ventricular mass in the elderly. The Cardiovascular Health Study.

Left ventricular (LV) mass, as estimated from M-mode echocardiography (echo), has previously been shown to be an independent predictor of incident cardiovascular disease morbidity and mortality. We evaluated the relationship at baseline of echo LV mass to relevant cardiovascular disease risk factors and other potential covariates in the Cardiovascular Health Study, multicenter study sponsored by the National Heart, Lung, and Blood Institute of 5201 men and women aged 65 years or older (mean, 73). Two-dimensionally directed M-mode echo LV mass measurements could be obtained in 1357 men and 2053 women (66% of this elderly cohort). Stepwise linear regression analyses of the relationship of echo LV mass to demographic and risk factor, physical activity, electrocardiographic, and prevalent disease variables resulted in a model that explained 37% of the variance for the entire cohort. In order of decreasing importance, factors positively associated with echo LV mass were body weight, male sex, systolic pressure, presence of congestive heart failure, present smoking, major and minor electrocardiographic abnormalities, treatment for hypertension, valvular heart disease, aortic regurgitation by color Doppler, and mitral regurgitation by color Doppler (in men) whereas diastolic pressure, bioresistance (a measure of adiposity), and high-density lipoprotein cholesterol were inversely related to echo LV mass. Although height and weight were both related to LV mass, height added nothing once weight was entered in multiple linear regression analyses. Furthermore, in the multiple regression models, diastolic pressure was inversely and systolic BP positively related to LV mass, with similar magnitudes for their coefficients. In consonance with these findings, pulse pressure was positively related to LV mass in bivariate analyses. Multiple linear regression analyses explained less of the variance for ventricular septal thickness (R2 = .13) and LV posterior wall thickness (R2 = .14) than for LV mass (R2 = .37) and LV diastolic dimension (R2 = .27). Intriguing findings in the elderly Cardiovascular Health Study cohort included the presence of pulse pressure as a positive correlate, and high-density lipoprotein cholesterol as an inverse correlate, of LV mass. Longitudinal studies in the Cardiovascular Health Study cohort will help to clarify the importance of demographic, risk factor, and other variables, and changes in these variables, in predicting changes in echo LV mass and its components as well as the prognostic significance of LV mass in the elderly.

Vitamin B(12) deficiency and depression in physically disabled older women: epidemiologic evidence from the Women's Health and Aging Study.

OBJECTIVE: It has been hypothesized that adequate concentrations of vitamin B(12) and folate are essential to maintain the integrity of the neurological systems involved in mood regulation, but epidemiologic evidence for such a link in the general population is unavailable. This study examined whether community-dwelling older women with metabolically significant vitamin B(12) or folate deficiency are particularly prone to depression. METHOD: Serum levels of vitamin B(12), folate, methylmalonic acid, and total homocysteine were assayed in 700 disabled, nondemented women aged 65 years and over living in the community. Depressive symptoms were measured by means of the Geriatric Depression Scale and categorized as no depression, mild depression, and severe depression. RESULTS: Serum homocysteine levels, serum folate levels, and the prevalences of folate deficiency and anemia were not associated with depression status. The depressed subjects, especially those with severe depression, had a significantly higher serum methylmalonic acid level and a nonsignificantly lower serum vitamin B(12) level than the nondepressed subjects. Metabolically significant vitamin B(12) deficiency was present in 14.9% of the 478 nondepressed subjects, 17. 0% of the 100 mildly depressed subjects, and 27.0% of the 122 severely depressed women. After adjustment for sociodemographic characteristics and health status, the subjects with vitamin B(12) deficiency were 2.05 times as likely to be severely depressed as were nondeficient subjects. CONCLUSIONS: In community-dwelling older women, metabolically significant vitamin B(12)deficiency is associated with a twofold risk of severe depression.

Vitamin D deficiency among older women with and without disability.

BACKGROUND: Vitamin D deficiency is associated with bone loss and bone fractures, and the identification of vulnerable populations is important to clinical practice and public health. OBJECTIVE: The objectives of this study were to determine the prevalence of vitamin D deficiency and to examine associated risk factors for vitamin D deficiency in older women. DESIGN: We measured serum concentrations of 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1, 25(OH)(2)D], intact parathyroid hormone (PTH), osteocalcin, and ionized calcium in women aged >/=65 y who were participating in the Women's Health and Aging Study I, an observational study of women representing the approximately one-third most disabled women living in the community, and women aged 70-80 y who were participating in the Women's Health and Aging Study II, an observational study of women among the two-thirds least disabled women living in the community in Baltimore. RESULTS: The women were classified into 4 domains of physical disability. Among 371 women with 0 or 1 domain of disability and 682 women with >/=2 domains of disability, 6.2% and 12.6%, respectively, had vitamin D deficiency [serum concentrations of 25(OH)D < 25 nmol/L]. In univariate analyses, risk factors for vitamin D deficiency included increasing age, black race, low educational level, high body mass index, high triceps skinfold thickness, increasing level of disability, winter season, and elevated creatinine concentration. In multivariate models, black race had a strong association with vitamin D deficiency when other risk factors were adjusted for. CONCLUSIONS: Vitamin D deficiency, a preventable disorder, is a common and important public health problem for older disabled women living in the community; black women are at higher risk than are white women.

Racial differences in prevalence of cobalamin and folate deficiencies in disabled elderly women.

BACKGROUND: Many previous investigations of cobalamin and folate status were performed in white populations. OBJECTIVE: Our objective was to determine whether there are racial differences in the prevalence of cobalamin and folate deficiency. DESIGN: The study was a cross-sectional comparison of baseline serum cobalamin, folate, methylmalonic acid (MMA), total homocysteine (tHcy), and creatinine concentrations, complete blood count, and vitamin supplementation in 550 white and 212 African American subjects from a cohort of physically disabled older women. RESULTS: The mean (+/-SD) serum MMA concentration was significantly higher in whites than in African Americans: 284 +/- 229 compared with 218 +/- 158 nmol/L (P = 0.0001). tHcy concentration was higher in African Americans than in whites: 12.4 +/- 7.0 compared with 10.9 +/- 4.6 micromol/L (P = 0.001). Serum cobalamin was lower in whites (P = 0.0002). Cobalamin deficiency (serum cobalamin <258 pmol/L and MMA >271 nmol/L) was more frequent in the white women (19% compared with 8%; P < 0.0003). Folate deficiency (serum folate <11.4 nmol/L, tHcy >13.9 micromol/L, and MMA <271 nmol/L) was more prevalent in African Americans than in whites (5% compared with 2%; P = 0.01). Multivitamin use was associated with lower tHcy but not with MMA concentrations. Regression models showed that age >85 y, African American race, serum creatinine >90 micromol/L, and high MMA concentration were all significantly correlated with higher tHcy. Creatinine > 90 micromol/L, white race, and folate concentration were positively associated with MMA concentration. CONCLUSIONS: Cobalamin deficiency with elevated serum MMA concentration is more prevalent in elderly white than in African American women and elevated serum tHcy and folate deficiency are more prevalent in elderly African American than in white women.