Obesity is the major determinant of the abnormalities in blood pressure found in young women with the polycystic ovary syndrome.

CONTEXT: Obesity and insulin resistance predispose patients with the polycystic ovary syndrome (PCOS) to abnormalities in blood pressure regulation.
OBJECTIVE: Our objective was to evaluate the impact of obesity on the blood pressure profiles of PCOS patients. PATIENTS, SETTING, AND
DESIGN: Thirty-six PCOS patients and 20 healthy women participated in a case-control study at an academic hospital. MAIN OUTCOME MEASURES: We conducted ambulatory blood pressure monitoring and office blood pressure determinations.
RESULTS: Hypertension (defined as increased office blood pressure confirmed by ambulatory blood pressure monitoring or by masked hypertension) was present in 12 PCOS patients and eight controls (P = 0.618). No differences between patients and controls were found in office and ambulatory blood pressure monitoring values and heart rate, yet the nocturnal decrease in mean blood pressure was smaller in patients (P = 0.038). Obese women (13 patients and eight controls) had increased frequencies of office hypertension (29% compared with 3% in lean plus overweight women, P = 0.005), increased diastolic (P = 0.009) and mean (P = 0.015) office blood pressure values, and increased heart rate values during the daytime (P = 0.038), nighttime (P = 0.002), and 24-h (P = 0.009) periods, independently of having PCOS or not. The frequency of a nocturnal nondipper pattern was 62% in obese PCOS patients, compared with 26% in lean plus overweight PCOS patients (P = 0.036) and 25% in obese and in lean plus overweight controls.
CONCLUSIONS: Abnormalities in the regulation of blood pressure are common in young women with PCOS, yet, with the exception of the nondipper pattern, these abnormalities result from the frequent association of this syndrome with obesity.