Polycystic ovary syndrome (PCOS) is one of the most common female endocrine disorders. PCOS is a complex endocrine and gynecological disorder thought to be genetic. PCOS is found in approximately 5% of women of reproductive age. It is a leading cause of female infertility and certainly the most frequent endocrine problem in women of reproductive age. I have written about PCOS before.
- Review: Vitamin D and polycystic ovary syndrome. Posted on May 28, 2012 by John Cannell, MD
- RCT: Heart health and polycystic ovarian syndrome. Posted on June 11, 2012 by John Cannell, MD
The principal features of PCOS are lack of ovulation resulting in irregular periods, few or no periods, infertility, and ovaries with multiple cysts. Women with PCOS also have excessive male hormone levels resulting in acne and hairiness. They also have insulin resistance, are often obese with type 2 diabetes, hypertension, and high cholesterol. The symptoms vary greatly among affected women. Diazoxide (Proglycem), an anti-hypertensive that also decreases insulin secretion, is often used to treat PCOS.
Dr John Nestler and colleagues of the Medical College of Virginia recently tested vitamin D levels on eight women with PCOS, before and after treating them with diazoxide 100 mg three times per day for 12 days.
Nestler JE, Reilly ER, Cheang KI, Bachmann LM, Downs RW Jr. A pilot study: effects of decreasing serum insulin with diazoxide on vitamin d levels in obese women with polycystic ovary syndrome. Trans Am Clin Climatol Assoc. 2012;123:209-20.
At baseline, the 8 women with PCOS had significantly lower 25(OH)D than did the 9 controls (P =0.012). The prevalence of vitamin D deficiency, defined as a serum 25(OH)D level < 20 ng/mL, was 100% in the PCOS group versus 55.6% in the 9 members of the control group. The prevalence of severe vitamin D deficiency, defined as a serum 25(OH)D level < 10ng/mL, was 87.5% in the PCOS group versus 22.2% in the control group. Vitamin D binding protein and activated vitamin D levels did not differ significantly between the two groups at baseline.
After 12 days of diazoxide treatment, the 25(OH)D levels of the women with PCOS went from a mean of about 7.5 ng/ml to 10.5 ng/ml. However, the 25(OH)D levels of the 9 control women fell from 15 ng/ml to 10 ng/ml. In the PCOS women on diazoxide, the serum testosterone and the serum insulin fell significantly.
As their number are quite small, only a few conclusions about diazoxide treatment can be gathered by this paper. It is helpful in treating PCOS by lowering insulin and testosterone levels.
Does diazoxide also raise vitamin D levels? The paper found it did but the levels of the control group fell for unknown reasons (the season of the year of the study was not disclosed), so no significant differences between groups were noted. Perhaps diazoxide also raises vitamin D levels and that may be one of its mechanisms of action, much like the statins.