Trends in PCOS diagnoses

Trends in PCOS diagnoses | Image Credit: © SewcreamStudio - © SewcreamStudio - stock.adobe.com.

According to a recent study published in the American Journal of Obstetrics & Gynecology, the incidence of polycystic ovary syndrome (PCOS) diagnoses among young US women has increased over time.

PCOS is the endocrine disorder most often experienced by reproductive women, presenting as ovulatory dysfunction, hyperandrogenism, and characteristic polycystic ovarian morphology. Associated negative outcomes include obesity, infertility, insulin resistance, and increased risk of, “cardiometabolic dysfunction and untoward long-term health sequelae.”

About 1 in 7 US women are impacted by PCOS, causing over $8 billion in health care costs per year. Despite these consequences, up to 75% of individuals with PCOS are not diagnosed clinically, indicating a lack of accurate population-based estimates. Variations in estimates are seen worldwide based on study methodologies, years and population studies, diagnostic criteria, and case identification.

To determine the incidence of prevalence of PCOS in US women and assess patterns over time, investigators conducted a study with data from an integrated health care delivery system called Kaiser Permanente Washington (KPWA). An estimated 700,000 individuals were included in the system as of January 2020.

Data on health plan enrollment, health care utilization, diagnoses, demographics, pharmacy dispensing, procedures, laboratory, and radiology results of members enrolled in KPWA from January 2006 to January 2019 was collected. Participants were female individuals aged 12 to 40 years between 2006 and 2019.

Patients with 3 or more years enrolled in KPWA and at least 1 health encounter during that time were included. Exclusion criteria included history of hysterectomy, oophorectomy, congenital or late-onset adrenal hyperplasia, benign neoplasm of the pituitary gland, adrenogenital disorder, Cushing syndrome, and hyperprolactinemia.

Age groups included 16 to 20 years, 21 to 25 years, 26 to 30 years, 31 to 35 years, and 36 to 40 years. Race and ethnicity data was also collected to determine health inequities based on race. Additional data included the type of provider who assigned the PCOS diagnosis, parity, premature menarche, and family history of PCOS.

A PCOS diagnosis based on the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code or ICD-10 code during an in-person visit was the primary outcome of the analysis. Incident cases were those diagnosed during the study period, while prevalent cases were all diagnoses before the end of 2019.

Two trained medical record abstractors reviewed the medical records of patients. Patients were categorized as definite, probable, or possible incident PCOS, prevalent PCOS, not PCOS, or unable to be classified. The 2003 Rotterdam criteria was used to determine incident PCOS case status.

There were 177,527 participants in the final analysis, contributing 586,470 person-years. Patients with an incident PCOS diagnosis were aged an average 23.6 years and had a mean body mass index (BMI) of 31.6 kg/m^2, while those without an incident PCOS diagnosis were aged an average 26 years and had a mean BMI of 26.3 kg/m^2.

Individuals with incident PCOS were more often non-Hispanic White, Pacific Islander, and Native American, and were more likely to have a family history of PCOS and be nulliparous. Participants were aged a mean 26.9 years at diagnosis.

Overall, there were 2491 cases of incident PCOS among the study population, for an incidence rate of 42.5 per 10,000 person-years. The incidence rate per 10,000 person years decreased from 50.5 in 2006 to 45.8 in 2019 among individuals aged 16 to 40 years.

A significant increase was found among individuals aged 16 to 20 years, while a decrease was found among individuals aged 26 to 30 years. However, incidence rates were greatest among patients aged 26 to 30 years, with similar rates observed across race and ethnicity groups.

In 2019, PCOS had an overall prevalence of 5.2%. The prevalence of PCOS was 7.6% in Pacific Islander individuals, 6.9% in Native American individuals, and 6.8% in Hispanic individuals. Pacific Islander individuals aged 31 to 35 years and Native American individuals aged 36 to 40 years had the highest rates of PCOS.

Of diagnosed PCOS cases, 60% were probable or definite, 14% possible, 17% prevalent, 7% not PCOS, and 2% not classifiable. Frequent health care use was seen in individuals diagnosed with PCOS, with high rates of outpatient visits before and after diagnosis.

Overall, increased rates of PCOS incidence were found among younger individuals. Investigators recommended health care professionals use these findings to adequate resources to individuals with PCOS.

Reference

Yu O, Christ JP, Schulze-Rath R. Incidence, prevalence, and trends in polycystic ovary syndrome diagnosis: a United States population-based study from 2006 to 2019. American Journal of Obstetrics & Gynecology. 2023;229(1). doi:10.1016/j.ajog.2023.04.010