Association of serum levels of vitamin D and vitamin D binding protein with mental health of overweight/obese women: A cross sectional study

Abstract

Mood disorders such as anxiety, depression, stresses, and low sleep quality are common among overweight/obese women. The relation of vitamin D and its blood carrier, vitamin D binding protein (VDBP), to mental health is still unknown. This study aimed to examine the relation of serum 25(OH)D and VDBP to mental health measures including depression, anxiety, stress and sleep quality of overweight/obese women. This cross-sectional study included a total of 265 overweight/obese women in Tehran, Iran, from 2016 to 2017. The 21-question version of the Depression Anxiety Stress Scales (DASS-21) and the Pittsburgh Sleep Quality Index (PSQI) were used to evaluate mental health and sleep quality of participants, respectively. Serum 25(OH)D was assessed using the radioimmunoassay method and VDBP was evaluated with the use of ELISA. Associations were tested by logistic regression analysis. In the crud analysis, higher serum 25(OH)D was marginally related to decreased odds of stress, but, women with higher VDBP levels had a marginal increased risk for depression. After adjustment for age, educational level, physical activity, body mass index and dietary energy intake, higher serum 25(OH)D was significantly related to a 42% decreased odds of stress (OR=0.58, 95%CI: 0.28-0.99, p=0.04), while, women with higher VDBP levels had an increased risk for depression (OR=1.74, 95%CI: 1.002-3.42, p=0.04). Serum vitamin D and VDBP were not significantly related to other indices of mental health. Higher serum vitamin D was related to decreased odds of stress but higher VDBP was related to increased odds of depression.