Background:
Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women at reproductive age, which is characterized by
obesity, hyperandrogenemia, and
insulin resistance (IR). This study aimed to investigate the
vitamin D status, and analyze the relationship between
vitamin D deficiency and metabolic risk factors in PCOS women in Shaanxi China. Methods: A cross-sectional study included 169 women diagnosed with PCOS and 114 control women without PCOS. The serum 25(
OH)D and metabolic markers were measured.
Vitamin D deficiency was defined as serum 25(
OH)D concentration less than 20 ng/mL. The primary outcome was the difference in
vitamin D status between the PCOS and control groups, the secondary outcomes were correlations between serum 25(
OH)D concentration and metabolic risk factors in women with PCOS. Results: The serum 25(
OH)D concentration was significantly lower in women with PCOS than in controls (P < 0.05), and the prevalence rates of 25(
OH)D deficiency and insufficiency were significantly higher in women with PCOS than in controls (P < 0.05). The serum 25(
OH)D concentration was significantly lower in PCOS women with
obesity or IR than in women without
obesity or IR (P < 0.05), and the prevalence of 25(
OH)D deficiency in PCOS women with
obesity or IR was significantly higher than in women without
obesity or IR (P < 0.05). Serum 25(
OH)D concentration was significantly negatively correlated with body mass index (BMI), waist-to-hip ratio (WHR), fasting
insulin, homeostasis model assessment of
insulin resistance (HOMA-IR), total
cholesterol,
low-density lipoprotein cholesterol (
LDL-C), and
high-sensitivity C-reactive protein (
hs-CRP) (P < 0.05). In comparison, serum 25(
OH)D concentration was significantly positively correlated with
high-density lipoprotein cholesterol (HDL-C) (P < 0.05). Increased BMI and WHR, high levels of fasting
insulin, HOMA-IR, total
cholesterol, LDL-C and
hs-CRP were regarded as risk factors, but high level of HDL-C was considered to be protective factor of
vitamin D deficiency in PCOS women. Conclusions:
Vitamin D deficiency is prevalent in PCOS women in Shaanxi China, especially in those with
obesity and IR. The serum 25(
OH)D level was correlated with metabolic risk factors in PCOS women. Multi-center randomized controlled trials with large sample sizes are needed to probe the metabolic effect of
vitamin D supplementation in PCOS women.