In patients with polycystic ovary syndrome (PCOS) metabolic changes persisted and waist circumference increased over two decades of follow-up, although hormonal parameters improved, in a longitudinal study from Italy.

A total of 233 women with PCOS, aged 20-25 years, were recruited to the study in Palermo, of whom 193 were followed up five-yearly for 20 years. Diagnosis of PCOS was confirmed by the presence of at least two of the following: chronic anovulation, clinical or biochemical hyperandrogenism, and polycystic ovaries on ultrasound. The control group consisted of 35 healthy women in the same age range with normal body weight.

Compared with the baseline comparison group, women with PCOS had a significantly higher mean BMI, waist circumference and ovarian volume measured by ultrasound. Their LH:FSH ratios and serum testosterone were also significantly higher as were their fasting insulin and quantitative insulin sensitivity check index (QUICKI) — a measure of insulin resistance.

Over two decades BMI remained fairly static in women with PCOS although waist circumference increased slightly, becoming significant after 15 years, P < 0.05.

After 10 years androgen levels decreased significantly, P < 0.05. There was a small but non-significant drop in LH and LH:FSH ratios after 20 years and a significant reduction in ovarian volume, P < 0.01. The number of women with ovulatory cycles had increased from 52 to 85 (44%) by the end of the follow-up period and 18 women (8%) could no longer be diagnosed as having PCOS.

PCOS severity based on phenotypical features improved steadily over the years but QUICKI and fasting insulin levels did not decrease.

The outcomes in women treated with the combined oral contraceptive pill or the insulin sensitiser metformin were no different from those who did not receive treatment.

It is the clinical manifestations of PCOS (amenorrhoea, infertility, hirsutism) rather than its underlying metabolic anomalies that generally drive women to present for treatment.

PCOS is considered by some to be the ovarian manifestation of the metabolic syndrome and as such may be a marker for enhanced future risk of cardiovascular disease and diabetes. This study confirms this view.

The message I took from this paper is that although some of the manifestations of PCOS may abate with time the high risk metabolic abnormality underlying the condition (insulin resistance) does not.

Women with PCOS should be viewed as a group at enhanced risk of CHD and type 2 diabetes and should be identified for preventative interventions. My first step in managing these patients is to advise a low-carbohydrate/low-glycaemic index diet to address their hyperinsulinism and insulin resistance.

Dr Chris Barclay