Vitamin D is a hormone produced in the skin via a non-enzymatic process involving ultraviolet light.It is well known that the physiology of aging makes older people particularly susceptible to... Show moreVitamin D is a hormone produced in the skin via a non-enzymatic process involving ultraviolet light.It is well known that the physiology of aging makes older people particularly susceptible to vitamin D deficiency and that, if untreated, it can have serious health consequences. This thesis deliberates on the topics of vitamin D supplementation in older people in light of the current guidelines and on the possible additional effects of ultraviolet light beyond vitamin D synthesis on nursing home residents. We present a cross-sectional study in nursing home residents aged 70 years and over designed to evaluate the efficacy of vitamin D supplementation in achieving vitamin D sufficiency. We also discuss the different supplementation strategies for nursing home residents and community dwelling persons aged 70 years and over based on a survey administered to general practitioners and elderly care physicians in the Netherlands.In the second part we concentrate on additional effects of ultraviolet light beyond vitamin D synthesis. We describe our systematic review of literature on the effect of ultraviolet light, when applied to the skin or eyes, on mood, depression and well-being. We present also our randomized controlled trial on the effect of ultraviolet radiation compared with oral vitamin D supplementation on the well-being of nursing home residents with dementia. Further we use the data of the RCT to carry out a post-hoc analysis to compare the effect of vitamin D alone compared with ultraviolet radiation on the blood pressure of old people with dementia. Show less
Background Observational studies have reported an inverse association between ultraviolet (UV) radiation and hypertension. The aim of this study was to assess differences in blood pressure changes... Show moreBackground Observational studies have reported an inverse association between ultraviolet (UV) radiation and hypertension. The aim of this study was to assess differences in blood pressure changes between persons with dementia receiving UV light versus vitamin D (VD) supplementation. Methods Post-hoc analysis of randomized controlled trial data concerning nursing home residents with dementia (N = 61; 41 women, mean age 84.8 years). The participants received half-body UV irradiation, twice weekly over 6 months, at one standard erythema dose (UV group, n = 22) or 5600 international units of cholecalciferol once a week (VD group, n = 39). Short-term effects were evaluated after 1 month and long-term effects after 3 and 6 months. Differences in blood pressure changes were assessed using linear mixed models. Results With the VD group as a reference, the estimated difference in mean change of systolic blood pressure was - 26.0 mmHg [95% confidence interval (CI) -39.9, - 12.1, p = .000] at 1 month, 4.5 mmHg (95% CI -6.8, 15.9, p = 0.432) at 3 months, and 0.1 (95% CI -14.1, 14.3, p = 0.83) at 6 months. The estimated difference in diastolic blood pressure was - 10.0 mmHg (95% CI -19.2, - 0.7, p = 0.035) at 1 month, 3.6 mmHg (95% CI -4.1, 11.2, p = 0.358) at 3 months, and 2.7 (95% CI -6.8, 12.1, p = 0.580) at 6 months. Conclusions UV light had only a short-term effect but not a long-term effect on blood pressure reduction compared to VD use in this sample of normotensive to mild hypertensive nursing home residents with dementia. Future studies will be needed to determine the effect of UV light in different samples of the population and especially in a population with hypertension. Show less
There are indications that ultraviolet B (UVB) exposure has beneficial effects on well-being through mechanisms other than vitamin D synthesis alone. We conducted a randomized controlled... Show moreThere are indications that ultraviolet B (UVB) exposure has beneficial effects on well-being through mechanisms other than vitamin D synthesis alone. We conducted a randomized controlled multicenter trial to compare the effects of UVB light and vitamin D supplementation (VD) in terms of the well-being of nursing home residents with dementia. Participants were randomly assigned to the intervention group (UVB group, n = 41; half-body UVB irradiation, twice weekly over 6 months, with 1 standard erythema dose (SED)) or to the control group (VD group, n = 37; 5600 International units (IU) cholecalciferol supplementation once a week). The main outcome was well-being, measured by the Cohen-Mansfield Agitation Inventory (CMAI) and the Cornell scale for depression in dementia at 0, 3, and 6 months. Secondary outcomes were QUALIDEM quality of life domains and biochemical parameters of bone homeostasis. Intention-to-treat analysis with linear mixed modeling showed no significant between-group differences on agitation (p = 0.431) or depressive symptoms (p = 0.982). At six months, the UVB group showed less restless/tense behavior compared to the VD group (mean difference of the mean change scores 2.2, 95% CI 0.8 to 3.6; p = 0.003 for group x time interaction) and lower serum 25(OH)D3 concentration (estimated mean difference - 21.9, 95% CI -32.6 to -11.2; p = 0.003 for group difference). The exposure of nursing home residents with dementia to UVB light showed no positive benefits in terms of wellbeing. UVB treatment may have a positive effect on the restless/tense behavior characteristic of advanced dementia but more research is needed to confirm this finding. Show less
