Sleep duration is associated with vitamin D deficiency in older women living in Macao, China: A pilot cross-sectional study

Abstract

Chinese women are known to have both a high prevalence of metabolic syndrome (MetS) and vitamin D deficiency (serum 25-hydroxyvitamin D (25OHD) <50 nmol/l). Associations between sleep duration and circulating 25OHD have recently been reported but, to our knowledge, these associations have not been studied in older Chinese populations. We thus investigated whether sleep duration was associated with vitamin D status in a population from Macao, China, and whether sleep duration modified the association between MetS and vitamin D deficiency. In 207 older (>55 years) Macanese, anthropometry, blood samples and validated questionnaires, including sleep duration and cardiovascular risk factors, were simultaneously collected. On multivariable categorical analyses, those women, not men, who had short sleep duration (�6 hours (h)) were at a 2-fold risk for vitamin D deficiency (both <50 nmol/L and <37 nmol/L; OR = 1.94, 95%CI 1.29-2.92; OR = 2.05, 95%CI 1.06-3.98, respectively) and those who had longer sleep duration (>8 h) were 3-fold more likely to have vitamin D deficiency (OR = 3.07, 95%CI 1.47-6.39; OR = 2.75, 95%CI 1.08-7.00, respectively) compared to those with normal sleep duration (6-8 h). Both women and men with MetS were 2-fold more likely to have vitamin D deficiency (women: OR = 2.04, 95%CI 1.31-3.17; OR = 2.15, 95%CI 1.11-4.17, respectively; men: OR = 2.01, 95%CI 1.23-3.28; OR = 2.04, 95%CI 1.00-4.29, respectively). Moreover, women with both short sleep duration and MetS had an increased risk of vitamin D deficiency (OR = 3.26, 95%CI 1.10-9.64). These associations were not found in those with longer sleep. Men with longer sleep and MetS had a 5-fold risk of vitamin D deficiency (OR = 5.22; 95%CI 2.70-10.12). This association was non-significant for men with shorter sleep. We conclude that both short and long sleep duration were associated with vitamin D deficiency in older Chinese women. Further research is needed in larger cohorts or with intervention studies to further examine the associations between reduced sleep, metabolic syndrome and vitamin D deficiency.

Associations of serum 25-hydroxyvitamin D and subjective sleep measures in an arctic population: Insights from the population-based Tromsø Study

“…Comparison with previous literature is complicated by the substantial variation in methodology, definition of outcomes and covariate adjustment across studies. A positive association between 25(OH)D and sleep duration, as found in some of our analyses, has been reported by others [ 15 , 16 , [18] , [19] , [20] , [21] , [22] , [23] ], although null findings have also been reported [ 40 , 41 ]. Moreover, a recent meta-analysis by Gao et al.…”

“…Higher concentrations of serum 25-hydroxyvitamin D (s-25(OH)D), the main circulating vitamin D metabolite, have been associated with longer and earlier night sleep [ 15 ]. Moreover, vitamin D deficiency has been associated with short sleep duration [ [16] , [17] , [18] , [19] , [20] , [21] , [22] , [23] ], poor self-reported sleep quality [ 24 , 25 ], and an increased risk of daytime sleepiness [ 26 , 27 ]. However, none of these previous studies have been performed in populations living in an Arctic area, in which the prevalence of both insufficient sleep duration and insomnia has been reported as worryingly high [ 28 ].…”

Vitamin D and sleep duration: a possible link

“…4 In contrast to our findings, Liu et al found that both long and short sleep duration was associated with vitamin D deficiency in older Chinese women. 5 Almost same findings were found by Choi et al who stated that differences in log-transformed vitamin D status between the sleep insufficient or excessive sleep groups and the normal range sleep groups were not significant. 6 Though Abboud et al did systematic review and included 19 studies where they got the other way round and found that vitamin D status is promising in improving sleep quality.…”

“…Recently, it has been proposed that vitamin D plays an important role in serotonin and melatonin regulation, which further indicates the relevance of vitamin D in mental health, especially the regulation of mood and sleep. 5 Vitamin D is an essential micronutrient during the growth and development of the human body, and 25hydroxyvitamin D [25(OH)D] is the most sensitive clinical marker for vitamin D status.…”

No improvement of sleep from vitamin D supplementation: insights from a randomized controlled trial

“…Several observational studies have reported an association between vitamin D deficiency and poor sleep health, including increased risk of short sleep duration [ [24] , [25] , [26] ], daytime sleepiness [ 27 , 28 ] and poor sleep quality [ 29 , 30 ]. Nevertheless, a causal link has been difficult to demonstrate, as results from randomized controlled trials (RCTs) are scarce.…”