Vitamin D levels linked to metabolic syndrome in PCOS patients

The new study by authors from Poland found that Vitamin D 25(OH) showed a significant negative correlation with metabolic syndrome, BMI, WHR (weight-height ratio), waist circumference, FAI index and blood pressure.

The authors conclude: “Unfortunately, the crucial role of meaningful supplementation tends to be forgotten—the main idea behind our study is to consider it as a therapeutic approach rather than a form of daily self-care and engage patients to engage in the treatment process by offering them a form of medicine that is easy for them to access.”

PCOS​

PCOS, a diverse hormonal condition that impacts the way ovaries work, affects 8-13%​ of women in their reproductive years. It stands as a prominent factor in infertility and showcases signs of hyperandrogenism​ like hirsutism​, acne, and irregular menstrual cycles.

A previous study​ already established a connection between vitamin D deficiency and the development of metabolic syndrome, hypertension, insulin resistance, and obesity, all of which are frequently associated with PCOS.

Previous research​ concluded that vitamin D deficiency should be considered as an additional risk factor in the development of PCOS, and recommended that vitamin D supplementation for women from identified deficiency areas can reduce the risk of PCOS development.

However, the authors of the new study note, that given the inconclusive nature of existing research, there is a need to examine the impact of vitamin D on metabolic syndrome and hormonal balance in patients with PCOS.

The study ​

The study enrolled 120 women, aged 18 to 42 years, who were divided into two groups: one consisted of individuals diagnosed with PCOS, while the other comprised women with regular menstrual cycles and no signs of androgenisation, thereby excluding PCOS.

Each participant underwent a comprehensive evaluation, including medical history, physical examination (including gynecological examination), and anthropometric measurements such as height, weight, waist circumference, and hip circumference. 

In addition, various blood parameters were analysed in participants, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, TSH, free thyroxine (ft4), prolactin (PRL), total testosterone, DHEASO4, 17-hydroxyprogesterone (17-OHP), sex-hormone-binding globulin (SHBG), androstenedione, and 25(OH) vitamin D3 metabolite.

The resulting data indicate that vitamin D 25(OH) has a significant negative correlation with the metabolic syndrome, BMI, WHR, waist circumference, and FAI index. Vitamin D showed a positive correlation with SHBG.

The report states: "Our study on patients with polycystic ovary syndrome showed an association of vitamin D with two of the five diagnostic criteria for the metabolic syndrome—waist circumference and blood pressure. Furthermore, a negative correlation with the presence of the metabolic syndrome in these patients was shown (r = −0.30; p = 0.008). In the control group, vitamin D showed no correlations with any of the parameters determined."

They add that in a univariate logistic regression analysis of vitamin D, it was shown that a unit increase in vitamin D reduces the odds of the metabolic syndrome in patients with PCOS by 7%. What's more, in Akbari et al.​ and Mansournia et al.​ meta-analyses, they pointed to the beneficial effect of vitamin D supplementation on the reduction in inflammation parameters. 

The report concludes: “Therefore, it may seem reasonable to supplement these patients with vitamin D to reduce their risk of developing the metabolic syndrome and cardiovascular complications."

The study found no significant differences in serum vitamin D concentrations between patients with PCOS and the control group (p = 0.238). However, the data does reveal a significant proportion of patients with PCOS had insufficient or suboptimal levels of serum vitamin D, with D deficiency found in as many as 42.5% of the women in the PCOS group, while suboptimal concentrations were found in 35%.

The authors conclude: “According to our research, more than half of the patients with PCOS had a BMI > 25 kg/m2.”

“Most authors agree on the association of vitamin D deficiency with excess body weight​,” they noted.

A previous study ​determined body-fat content in PCOS patients through X-ray absorptiometry and demonstrated that serum 25(OH)D levels are closely related to body-fat percentage.

With this knowledge, the authors of the new study hypothesise: “Vitamin D, as a fat-soluble substance,​ is retained in adipose tissue, preventing its conversion to active metabolites.”

Journal: Nutrients

https://www.mdpi.com/2072-6643/15/13/2952#B11-nutrients-15-02952​

“Influence of Vitamin D on the Incidence of Metabolic Syndrome and Hormonal Balance in Patients with Polycystic Ovary Syndrome"

Authors: Katarzyna Lejman-Larysz, Anna Golara, Marta Baranowska, Mateusz Kozłowski, Paweł Guzik, Iwona Szydłowska, Jolanta Nawrocka-Rutkowska, Elżbieta Sowińska-Przepiera, Aneta Cymbaluk-Płoska and Agnieszka Brodowska.