Body Composition, Obesity Increase Odds of Developing PCOS

A new study leveraging observational and genetic data from more than 100,000 patients provides clinicians with an overview of the relationship between markers of body composition, including body fat and metabolic parameters, and risk of developing polycystic ovary syndrome (PCOS).

Presented at the European Congress of Endocrinology 2022, results of the study demonstrate increased BMI, body fat percentage, fasting insulin, and sex-hormone-binding globulin (SHBG), were all associated with an increased likelihood of developing PCOS.

"This study shows that obesity during childhood and teenage years are key factors in the development of PCOS. This opens a way to support women’s health by investing in nutritional and weight management programs for younger people. This also has the potential to prevent the condition’s consequences which include poorer quality of life, infertility, diabetes, and pregnancy complications. Future research should focus on developing new ways to help women affected by PCOS manage their weight”, said Laurence Dobbie, MBChB, of the Royal Liverpool University Hospital in the United Kingdom, in a statement from the European Society of Endocrinology.

A common endocrine condition impacting up to 10% of women of childbearing age, research surrounding risk factors for development of PCOS have come into the spotlight of endocrine research efforts in recent years. The current study, which was conducted by Dobbie and colleagues at the Royal Liverpool University Hospital in the United Kingdom, was launched with the intent of investigating whether obesity and diabetes markers were associated with an increased likelihood of PCOS development. To do so, investigators designed their study to include a Mendelian randomization analysis as well as a systematic review and meta-analysis of studies assessing the impact of overweight and obesity on development of PCOS.

For the purpose of analysis, investigators conducted a 2-sample Mendelian randomization study to determine the impact of body composition and metabolic parameters on odds of PCOS. This PCOS genome-wide association study meta-analysis data, which included 10,074 people with PCOS and 103,164 controls, were interrogated using the inverse-variance weight method. After a search of relevant databases, investigators had identified 71 studies for inclusion in their systematic review and 63 for the meta-analysis that assessed the role of overweight, obesity, and central obesity on odds of PCOS in adults and adolescents.

In their Mendelian randomization analysis, significant associations were observed between body composition metrics and odds of developing PCOS, with every SD increase in BMI, which correlated to a BMI increase of 4.8 kg/m2, odds of PCOS more than doubled (OR, 2.76 [95% CI, 2.27-3.35]). Similar trends were observed with risk of PCOS and SD increases for body fat percentage (OR, 3.05 [95% CI, 2.24 - 4.15]), whole-body fat mass (OR, 2.53 [95% CI, 2.04-3.14]), fasting insulin (OR, 6.98 [95% CI, 2.02-24.13]) and sex-hormone binding globulin (OR, 0.74 [95% CI, 0.64-0.87]). Of note single SD increases for body fat percentage, whole-body fat mass, fasting insulin, and SHBG were 8.5%, 9.6 kg, 0.79 pmol/L, and 28 nmol/L, respectively. Investigators pointed out results indicated genetically determined childhood body size also increased odds of PCOS after adjustment for adult body size (OR, 2.56 [95% CI, 1.57-4.20]).

In their meta-analysis, investigators found women with overweight (OR, 3.80 [95% 2.87-5.03]), women with obesity (OR, 4.99 [95% CI, 3.74-6.67]), and women with central obesity (OR, 2.93 [95% CI, 2.08-4.12]) all had increased likelihood of developing PCOS. Additionally, results suggested presence of overweight (OR, 5.32) or obesity (OR, 7.86) in adolescence was associated with greater odds of PCOS than overweight (OR, 3.57) or obesity (OR, 4.66) in adulthood.

This study, “Body Composition during Childhood, Adolescence and Adulthood influences the odds of developing Polycystic Ovary Syndrome: A Mendelian Randomization Study with a Systematic Review and Meta-analysis,” was presented at the European Congress of Endocrinology 2022 annual meeting.