Screening for Vitamin D Deficiency in Black Americans: Comparison of Total, Free, Bioavailable 25 Hydroxy Vitamin D Levels with Parathyroid Hormone Levels and Bone Mineral Density.

OBJECTIVES: There is debate surrounding the adequacy of total and free 25 hydroxy vitamin D [25(OH)D] levels in black Americans who have inherently high bone mineral density [BMD] and low serum concentration of vitamin D binding proteins [VDBP]. DESIGN: Retrospective analysis of serum samples and BMD analyses from the African American Health Study [AAHS] cohort. SETTING: The AAHS is a population-based longitudinal study initiated to examine issues of disability and frailty among urban-dwelling black Americans in the city of Saint Louis, Missouri. PARTICIPANTS: 122 men and 206 women, age 60.2 ± 4.3 years. INTERVENTION: Retrospective analysis. MEASUREMENTS: Total 25(OH)D, VDBP, PTH, and BMD of the lumbar spine and hip by dual energy x-ray photometry (DXA). Free and bioavailable vitamin D levels were calculated using serum concentrations and affinity constants for the VDBP (Gc1F and Gc1S) phenotypes. RESULTS: Serum total 25(OH)D levels were 14.6 ± 8.9 ng/mL (36 ± 22 nmol/L). Vitamin D insufficiency was estimated by compensatory elevations of PTH above the normal range (> 65 pg/mL). PTH levels were within the normal reference range in > 95% of the samples at total 25(OH)D levels ≥ 20 ng/mL (≥50 nmol/L). There was no difference in the correlation of the reciprocal relationship of vitamin D vs parathyroid hormone between the VDBP phenotypes. Receiver operating characteristic curve analyses indicated that serum total 25(OH)D discriminated sufficiency from insufficiency at least as well as the calculated levels of the free and bioavailable vitamin D. Very low levels of total 25(OH)D (≤ 8 ng/mL, ≤20 nmol/L) were associated with decreased BMD (p=0.02), but higher levels of 25(OH)D did not show statistical differences in BMD. CONCLUSION: Total 25(OH)D levels of ≤ 8ng/mL (≤20 nmol/L) are associated with clinically significant changes in BMD, whereas total 25(OH)D levels ≥ 20 ng/mL (≥50 nmol/L) suppressed PTH and were not associated with deficiencies in BMD. Lower levels of 25(OH)D may be acceptable for bone health in black than in white Americans.

Frailty, Diabetes, and Mortality in Middle-Aged African Americans.

BACKGROUND: Older adult frail diabetics have high mortality risk, but data are limited regarding frail late middle-aged diabetics, especially for African-Americans. The aim of this study is to examine the association of diabetes with health outcomes and frailty in the African American Health (AAH) study. METHODS: AAH is a population-based longitudinal cohort study. Participants were African Americans (N=998) ages 49 to 65 years at baseline. Cross-sectional comparisons for diabetes included disability, function, physical performance, cytokines, and frailty. Frailty measures included the International Academy of Nutrition and Aging [FRAIL] frailty scale, Study of Osteoporotic Fractures [SOF] frailty scale, Cardiovascular Health Study [CHS] frailty scale, and Frailty Index [FI]). Longitudinal associations for diabetes included new ADLs ≥ 1 and mortality at 9-year follow-up. RESULTS: Diabetics were more likely to be frail using any of the 4 frailty scales than were non-diabetics. Frail diabetics, compared to nonfrail diabetics, reported significantly increased falls in last 1 year, higher IADLs and higher LBFLs. They demonstrated worse performance on the SPPB, one-leg stand, and grip strength; and higher Tumor Necrosis Factor receptors (sTNFR1 and sTNFR2). Mortality and 1 or more new ADLs also were increased among frail compared to nonfrail diabetics when followed for 9 years. CONCLUSIONS: Frailty in middle-aged African American persons with diabetes is associated with having more disability and functional limitations, worse physical performance, and higher cytokines (sTNFR1 and sTNFR2 only). Middle-aged African Americans with diabetes have an increased risk of mortality and frail diabetics have an even higher risk of death, compared to nonfrail diabetics.

Fruit and Vegetable Intake and Physical Activity as Predictors of Disability Risk Factors in African-American Middle-Aged Individuals.

OBJECTIVE: To investigate fruit and vegetable intake (FVI) and different dimensions of physical activity (PA) as predictors of change in disabilities and other known precursors of progressive disability in a population-based sample of African Americans. DESIGN: Longitudinal investigation of the independent associations of reported FVI and PA with six-year changes in disabilities and other known precursors of progressive disability. SETTING: Longitudinal study of a population-representative cohort of late middle-aged African Americans. PARTICIPANTS: 432 cohort participants with complete information on all measures. Measurements and Analytic Approach: During wave 8 (2008), FVI was measured using 2005 Behavioral Risk Factor Surveillance System questions and PA dimensions using the Yale Physical Activity Survey (YPAS). Disability measures included basic activities of daily living (ADLs) and instrumental ADLs (IADLs); other precursors included measured gait speed, grip strength, and short physical performance battery (SPPB) and reported lower body functional limitations (LBFLs) and FRAIL scale; these were measured at wave 4 (2004) and wave 10 (2010). Residual-change score linear regression was used to identify FVI and PA factors that were independently associated with six-year changes in disability and other precursors. RESULTS: The study cohort was less active than the YPAS-development group. Longitudinally, leisurely walking was independently associated with better ADL, IADL, grip strength, SPPB, LBFL, and frailty outcomes; standing with better IADL and SPPB; intake of vegetables other than carrots, salads, or potatoes with better grip strength and frailty; and fruit juice intake with worse grip strength and frailty. CONCLUSIONS: In this relatively inactive cohort, leisurely walking was associated with multiple beneficial outcomes. Benefits were also seen with vegetables other than potato intake, and fruit juice intake was associated with detrimental effects. This study highlights the importance of finding strategies to help this population increase PA (especially leisurely walking) and intake of whole fruits and vegetables.

FRAIL-NH Predicts Outcomes in Long Term Care.

BACKGROUND/OBJECTIVES: To investigate the predictive validity of the short, simple FRAIL-NH frailty screening tool in the long term care population and to then compare the predictive validity with the frailty index (FI) for 6-month adverse health outcomes. DESIGN: Retrospective study using the Minimum Data Set (MDS) 3.0 and chart review from June-December 2014. SETTING: Two Long Term Care Facilities in Saint Louis, MO. PARTICIPANTS: 270 patients ages ≥ 65 years old residing in long term care. MEASUREMENTS: Frailty was measured using the FRAIL-NH and Frailty Index (FI) criteria. Adverse outcomes measured at 6-month follow-up included falls, hospitalizations, and hospice enrollment/mortality. RESULTS: Based on screening tool used frailty prevalence was 48.7% for FRAIL-NH and 30.3% for FI. The FRAIL-NH pre-frail (Adjusted Odds Ratio [AOR]=2.62; 95% Confidence Interval [CI]=1.25-5.54; p=0.11) classification was associated with 6 month risk of falling and mortality/hospice enrollment was associated with the frail classification, AOR=3.96 (1.44-10.87, p=0.007). Combining the pre-frail and frail categories both measures predicted 6 month mortality with the FRAIL-NH being the strongest predictor (AOR=3.36; 95%CI=1.26-8.98; p=0.016) and the FI was a more modest predictor with an AOR of 2.28; 95%CI=1.01-5.15; p=0.047. When directly comparing the FRAIL-NH to the FI, the FRAIL-NH pre-frail were at increased risk of falling, AOR=2.42 (1.11-5.92, p=0.027) and the FRAIL-NH frail were at increased risk of hospice enrollment/death, OR=3.25 (1.04- 10.86) p=0.044. CONCLUSION: In comparison to the FI, the FRAIL-NH preformed just as well at screening for frailty and was a slightly better predictor of adverse outcomes. The FRAIL-NH is a brief, easy-to-administer frailty screening tool appropriate for long term care patients and predicts increased risk of falls in the pre-frail and mortality/hospice enrollment in the frail.