New research from Apple and the Harvard T.H. Chan School of Public Health sheds light on the connection between polycystic ovarian syndrome (PCOS), heart disease, and menstrual cycles.
PCOS is one of the leading causes of infertility in the United States. However, the cause of the condition is still unknown.
Preliminary data from Apple's and the Harvard T.H. Chan School of Public Health's Women’s Health Study found women with PCOS are more likely to have a family history of the condition and are more likely to have a number of diseases, including Type 2 diabetes.
While PCOS impacts between 9% and 18% of women of reproductive age, historically patients with the condition have faced a delayed diagnosis.
"Despite the association between PCOS and heart-related conditions, historically, research studies about heart health have not included information about menstrual cycles," Dr. Shruthi Mahalingaiah of the Harvard T.H. Chan School of Public Health said in a statement.
"More broadly speaking, menstrual health is also significantly under-represented in the research space. Our study is filling a research gap by diving deeper into understanding how periods and menstrual cycles can be a window into overall health.
"The level of research being conducted by the Apple Women’s Health Study is important for having a better understanding of PCOS and its health impacts, including for people with PCOS and those that might have PCOS, but do not know.”
Study participants answered a medical history survey, which asked about their health, as well as family history and a reproductive history survey. The Women's Health Study, which includes a cohort of roughly 30,000 women, found 12% of participants in the study had PCOS. Participants tracked their periods and symptoms on the Cycle Tracking feature on their Apple iPhone or Apple Watch.
Individuals with the condition were more likely to have family members with the condition (23%) than their peers without PCOS.
Researchers found that women with PCOS were more likely to have irregular periods than their peers without the condition. In fact, the research shows that 49% of participants with the condition never had a regular menstrual cycle before using hormones, compared to 22% of participants without PCOS.
Participants with PCOS were also more likely to have certain health conditions. For example, women with the condition were three times more likely to have Type 2 diabetes and two times more likely to have high blood pressure and cholesterol.
Just over 60% of individuals with PCOS reported having obesity, compared to 34.4% of participants without the condition. The study found that 5.6% of participants with the condition had irregular heartbeat or arrhythmia, whereas 3.7% of participants without PCOS demonstrated irregularities.
A study from the Endocrine Society found PCOS research is less funded than other disorders with a similar degree of morbidity and a similar or lower mortality prevalence. Apple and Harvard's T.H. Chan School of Public Health are looking to use the Women's Health Study to collect more data on the condition.
"Moving forward from this preliminary analysis, we hope to create a larger foundational data set on PCOS, with self-tracked variables, and its connection with heart health, which can contribute to understanding the condition, developing treatments, and inspiring new areas of research across women’s health," Mahalingaiah said.
"Our hope is that by expanding the understanding of the public health burden of PCOS, we can create research models that can be applied to further scientific understanding of other health conditions and the burden of other diseases.”
The Apple Women’s Health Study - Harvard T.H. Chan School of Public Health was first announced in 2019. In March 2021, researchers released a preliminary data analysis of the study, which included metrics about common menstrual symptoms.
Apple has teamed up with a number of research institutions on health research in the past. The tech giant worked with Stanford University on the Apple Heart Study, and the University of Michigan on hearing health research.