Interações entre sono e marcadores de padrões desfavoráveis de composição corporal ; Interactions between sleep and markers of unfavorable body composition

Background: Evidence suggests that patterns of body composition such as obesity, sarcopenia and sarcopenic obesity (SO) are associated with sleep changes beginning in middle age. Circadian hormonal oscillations also undergo significant transformations along aging and may affect body composition. However, investigations into the associations between sleep and body composition are still scarce. Objectives: To investigate, using three studies, the interactions between sleep and its disturbances with unfavorable patterns of body composition in adults. First, we evaluated the effects of a pharmacological agent on sleep and the hormonal axes involved in body metabolism in older men. Second, we analyzed the association between sleep and serum levels of 25-hydroxyvitamin D (25(OH)D), a possible mediator of muscle and lipid metabolism, in a sample from a clinical setting. Finally, we investigated associations of poor sleep markers and sleep disturbances with adverse body composition patterns in a population-based sample. Methods: In study 1, a double-blind, randomized, placebo-controlled, crossover clinical trial tested the effects of gabapentin 300mg on serum hormone levels and sleep parameters in healthy older men (>60 years). Nocturnal growth hormone (GH), testosterone, and cortisol serum measures were collected every 20 minutes. Polysomnography (PSG) measured the effects of the intervention on sleep structure and respiratory parameters. In study 2, PSG data and serum quantification of 25 (OH)D were analyzed in adults from a clinically evaluated sample. Logistic regression models assessed the cross-sectional associations between the risk of 25 (OH) D deficiency (<30 ng / mL) and indicators of poor sleep and sleep disorders. In study 3, in a population-based adult sample, sleep was evaluated by several methods, and electrical bioimpedance (BIA) evaluated body composition. Appendicular skeletal muscle mass (ASMM) adjusted for body mass index (BMI) morphologically defined sarcopenia (men <0.789; women ...