Abstract
Obesity is a multifactorial disease reflecting the interplay of biological and social factors. Lower socioeconomic status (SES), food insecurity, and poor sleep quality are risks factors for obesity; yet, our understanding of the physiological mechanisms behind overweightness is limited. Leptin, a hormone which modulates hunger, could be a potential mechanism because resistance can develop and lead to energy imbalances. Leptin levels tend to be elevated by low quality sleep; although etevidence shows lower SES people sleep poorly, there is a gap in the literature quantifying the relationship between leptin and SES. Hence, the objective of this research is to examine the influence of both sleep quality and SES on plasma leptin levels in a population undergoing rapid social change – the Yakut of northeastern Siberia. Survey (household assets, sleep quality) and biometric (anthropometry and plasma samples) data from 210 Yakut adults were used to test three hypotheses: (1) lower SES people experience lower quality sleep, 2) lower quality sleep correlates with higher leptin levels and 3) lower SES is correlated with higher leptin levels. We used principle component analysis to build a wealth scale and sleep quality score and ran a regression for each hypothesis, controlling for sleep duration, fatness, sex and age. Although we found no correlation between sleep quality and leptin levels or SES and leptin levels, lower SES people experienced significantly lower quality sleep relative to their higher SES peers (p<0.05). Our results indicate that SES could play a significant role in impacting sleep, an important physiological process. Future research should explore how lower quality sleep influences health outcomes, particularly mental health and levels of other hormones like insulin.