The following is a summary of “Incidence, prevalence, and trends in polycystic ovary syndrome diagnosis: a United States population-based study from 2006 to 2019,” published in the JULY 2023 issue of Obstetrics and Gynecology by Yu, et al.

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among women of reproductive age in the United States. However, there is a lack of US incidence estimates, and the prevalence estimates vary widely. For a population-based US study, researchers sought to estimate the incidence, prevalence, and trends of polycystic ovary syndrome, considering factors such as age, race and ethnicity, and diagnosing provider type.

The retrospective cohort study used data from patients enrolled in Kaiser Permanente Washington from 2006 to 2019. Female members aged 16 to 40 years with at least 3 years of enrollment and at least 1 healthcare encounter during that time were eligible for inclusion. Patients with a history of oophorectomy or hysterectomy were excluded. PCOS cases were identified using the International Classification of Diseases diagnosis codes (ICD-9 256.4 or ICD-10 E28.2). Incidence rates were adjusted by age using direct standardization to the 2010 US census data. Temporal trends in incidence were assessed using weighted linear regression (overall) and Poisson regression (by age, race and ethnicity, and provider type). Prevalent cases were defined as patients with a PCOS diagnosis before the end of 2019. The validity of incident cases identified by ICD codes was verified through medical record review.

Among 177,527 eligible patients contributing 586,470 person-years, 2,491 incident PCOS cases were identified. The mean age at diagnosis was 26.9 years, and the mean body mass index was 31.6 kg/m². Overall incidence was 42.5 per 10,000 person-years, with similar rates over time. However, incidence increased among individuals aged 16 to 20 (31.0 to 51.9 per 10,000 person-years, P=0.01) and decreased among those aged 26 to 30 (82.8 to 45.0 per 10,000 person-years, P=0.02). A small decreasing temporal trend in incidence rates was observed among non-Hispanic White individuals (P=0.01). The incidence rates by diagnosing provider type remained relatively stable over time. In 2019, among 58,241 patients contributing person-time, 3,036 (5.2%) had a PCOS ICD diagnosis code. 

The prevalence was highest among the Hawaiian and Pacific Islander group (7.6%), followed by Native American and Hispanic groups. Medical record review classified 60% as definite or probable incidents, 14% as possible incidents, and 17% as prevalent PCOS. The overall positive predictive value of the PCOS ICD diagnosis code for identifying definite, probable, or possible incident PCOS was 76% (95% CI, 72%–79%).

The study observed stable rates of incident PCOS diagnoses in a nonselected female cohort in the United States over time. The incidence of PCOS was 4- to 5-fold greater than reported in the United Kingdom. The prevalence of PCOS (5.2%) was nearly double the published US estimates (2.9%) based on ICD codes. Race, ethnicity, and provider type did not significantly impact temporal rates. Incident diagnoses increased in younger age groups and decreased in older age groups, possibly due to changing practice patterns with increased awareness of PCOS’s impact on long-term health outcomes and improved prevention efforts. Additionally, increasing obesity rates may be a contributing factor to the earlier ages at diagnosis.

Source: ajog.org/article/S0002-9378(23)00241-7/fulltext