Insufficient vitamin D scenario is associated with poor sleep quality during the pandemic: a population-based study, COVIDInconfidentes

ABSTRACT

Introduction: Hypovitaminosis D is a global health problem that affects more than one billion people worldwide, and this prevalence is expected to have increased during a pandemic with social restriction measures. Vitamin D has been implicated in extraskeletal functions in many physiological mechanisms, including sleep. Objective: To evaluate the association of vitamin D scenario with sleep quality during the COVID-19 pandemic. Methods: Cross-sectional, populationbased study, between October and December 2020 in two medium-sized cities in Minas Gerais. Sleep was assessed by the Pittsburgh Sleep Quality Index (PSQI), with a global score from 0 to 21. Scores of 5-10 indicate poor sleep quality. We evaluated a possible scenario of vitamin D adequacy, considering the time of sun exposure and the consumption of food supplements that are sources of vitamin D. Thus, we classified the vitamin D scenario as sufficient when the average daily sun exposure was greater than or equal to 30 minutes/day or the individual reported consuming a food supplement that is a source of vitamin D. And insufficient individuals who expose themselves to the sun for less than 30 minutes/day or do not consume a food supplement that is a source of vitamin D. Multiple logistic regression was used to verify the association of insufficient vitamin D scenario with sleep quality. Results: Of the individuals evaluated, most were female (51.9%), black or brown (67.9%), with minimum high school education (56.5%), and family income below 5 minimum wages (60.4%). Regarding vitamin D, 35.0% had insufficient sun exposure (< 30min/day), 77.9% did not use vitamin D source supplements. Evaluating the vitamin D scenario, 27.1% were insufficient. The mean of PSQI score was 6.32 (95%CI 6.03-6.62) e 52.5% had poor quality. In multivariate analysis, adjusted for sex, age, and income, subjects with insufficient vitamin D had 1.41 times the chance of having poor sleep quality (OR=1.41;95% CI 1.01-1.98). Conclusion: Individuals with insufficient vitamin D scenario are more likely to have poor sleep quality during the pandemic of COVID-19. Thus, this study demonstrates the importance of evaluating the impact of the pandemic on health conditions like vitamin D, and how they relate to sleep.