Vitamin D Deficiency Is Associated With Impaired Muscle Strength And Physical Performance In Community-Dwelling Older Adults: Findings From The English Longitudinal Study Of Ageing.

PURPOSE: Maintaining skeletal muscle function throughout life is a crucial component of successful ageing. Adequate vitamin D status may be important in preserving muscle function. We aimed to determine the association between impaired muscle function and serum vitamin D status in community-dwelling older adults. Falls were explored as a secondary aim. METHODS: Data were analyzed from adults aged ≥60 years, from Wave 6 of the English Longitudinal Study of Aging (ELSA). Handgrip strength (HGS) and the short physical performance battery (SPPB) were employed as measures of muscle strength and physical function, respectively. Serum 25-hydroxyvitamin D [25(OH)D] was assessed with concentration <30 nmol/L classed as vitamin D deficient. RESULTS: The study comprised 4157 community-dwelling adults with a mean age of 69.8 (SD 6.9). Overall, 30.6% had low HGS and 12.7% had low SPPB (≤6). Participants with the lowest serum 25(OH)D (<30 nmol/L) had the highest prevalence of impaired muscle strength and performance (40.4% and 25.2%) compared with participants with levels ≥50 nmol/L (21.6% and 7.9%). Consistent with this, vitamin D deficiency (<30 nmol/L) was a significant determinant of low HGS (OR 1.44 [1.22, 1.71], p<0.001) and poor physical performance (OR 1.65 [1.31, 2.09], p<0.001) in the logistic regression models. Older adults partaking in regular moderate physical activity had significantly lower odds of impaired muscle strength (OR 0.65 [0.58, 0.79]) and physical function (OR 0.30 [0.24, 0.38]), p <0.001, respectively. Single or multiple falls (15.8% and 10.5% in past year) were not associated with vitamin D status. CONCLUSION: Vitamin D deficiency was associated with impaired muscle strength and performance in a large study of community-dwelling older people. It is generally accepted that vitamin D deficiency at the <30 nmol/L cut-off should be reversed to prevent bone disease, a strategy that may also protect skeletal muscle function in ageing.

Caregiver Choice and Caregiver Outcomes: A Longitudinal Study of Irish Spousal Dementia Caregivers.

BACKGROUND: The perception of choice in becoming a caregiver may impact on caregiver psychological and physical health. We determined the proportion of spousal dementia caregivers who felt they had a choice, and examined whether lack of choice in taking up the caregiving role and the perceived degree of choice in caregiving predicted caregiver health and wellbeing and care-recipient placement in long-term care at 1-year follow-up. METHODS: We performed secondary analyses of data from DeStress, a longitudinal study of 251 spousal dementia caregivers in Ireland. We used multivariate logistic and linear regression analyses to examine whether lack of choice (a dichotomous item) and/or the perceived degree of choice (a 9-point scale) at baseline predicted caregiver health (number of chronic health conditions; self-reported health) and wellbeing (e.g., burden, anxiety, depression, stress, and positive aspects of caregiving) and care status (continued care at home or placement in long-term care) at follow-up. RESULTS: The vast majority of caregivers (82%) reported that they had no choice in taking up the caregiving role. Nevertheless, nearly three-quarters (74%) responded above the midpoint on the rating scale (Mean = 6.82, SD = 3.22; Median = 9; Mode = 9), indicating they provided care voluntarily. Caregivers who reported a greater degree of choice were more likely to still be providing care at home at follow-up and to identify benefits from providing care. Neither choice nor degree of choice predicted any other caregiver outcomes. CONCLUSION: For the vast majority of spousal dementia caregivers, taking up the caregiving role is not perceived as a choice; yet, most report performing this role voluntarily. Thus, facilitating greater choice may not necessarily diminish the key contribution family caregivers make to the care system. Although we found no evidence that caregiver choice predicted more positive caregiver health and wellbeing, the perception of choice is important in and of itself, and may benefit caregivers by facilitating the identification of positive aspects of care and be a factor in delaying care-recipient placement in long-term care. Future research should be especially mindful of how caregiver choice is assessed and how this may affect the resulting prevalence of choice.