Male hormone excess linked to impaired glucose metabolism and physical fitness in women
In her doctoral study, medical licentiate Katri Tuorila found that women of reproductive age with elevated male hormone levels showed particularly abnormal glucose metabolism and reduced cardiorespiratory fitness, commonly referred to as endurance capacity.
“Based on our results, hyperandrogenemia, especially when accompanied by overweight, appears to be an independent risk factor for cardiovascular disease in women. A surprising finding, however, was its association with reduced cardiorespiratory fitness, as previous studies have shown that male hormones can enhance physical performance,” says Tuorila.
“We interpret this finding to mean that, over the long term, elevated androgen levels manifest as metabolic challenges during intense physical exertion, reflecting the increased cardiovascular risk seen in hyperandrogenic women. At the same time, we observed that hyperandrogenemia was linked to greater muscle strength, which aligns with previous research,” she adds.
Hyperandrogenemia affects around one in ten women of reproductive age. The most common cause is polycystic ovary syndrome (PCOS), which itself increases the risk of glucose metabolism disorders and cardiovascular disease. Excess male hormones also promote central obesity and reduce insulin sensitivity, further exacerbating metabolic problems.
The study was conducted as part of the Northern Finland Birth Cohort 1966, which included 5,889 women. Participants were followed at ages 31 and 46 through questionnaires and clinical examinations, with data complemented by national registries. Hyperandrogenemia was defined using total testosterone levels and the free androgen index. Hormone levels were measured using precise liquid chromatography-tandem mass spectrometry, and analyses were also conducted separately for women without a PCOS diagnosis.
Medical licentiate Katri Tuorila will defend her dissertation at the University of Oulu on Friday, 31 October.