Brown adipose tissue thermogenesis in polycystic ovary syndrome

Summary Objective Polycystic ovary syndrome ( PCOS ) is associated with increased obesity with a greater propensity to weight gain and a lack of sustainable lifestyle interventions. Altered brown adipose tissue ( BAT ) thermogenesis is a potential contributor to obesity in PCOS . BAT activity and modulation have not been studied in PCOS . This observational study explored BAT thermogenesis and its associations in women with and without PCOS . Participants and methods Cutaneous temperature was recorded from supraclavicular (indicator of BAT activity) and upper arm regions using dataloggers (SubCue, Calgary, Canada) in a cross‐sectional substudy, nested within a randomized control trial, of community‐recruited premenopausal women with (n = 47, Rotterdam diagnostic criteria) and without (n = 11) PCOS . Results Complete temperature data were available in 44 PCOS (mean age: 30.0 ± 6.2, mean BMI : 29.3 ± 5.5) and 11 non‐ PCOS (mean age: 33.0 ± 7.0, mean BMI : 25 ± 3) women. Women with PCOS had lower supraclavicular skin temperature compared to controls overall (33.9 ± 0.7 vs 34.5 ± 1, P  < 0.05) and during sleep (34.5 ± 0.6 vs 35.2 ± 0.9, P  < 0.001). In the PCOS group, supraclavicular skin temperature overall and over sleep and waking hours correlated inversely with testosterone ( r  = −0.41 P  < 0.05, r  = −0.485 P  < 0.01 and r  = −0.450 P  < 0.01 respectively). Testosterone levels explained approximately 15%, 30% and 20% of the variability in supraclavicular skin temperature overall and over sleep and waking hours in women with PCOS , respectively. Conclusion Women with PCOS have lower BAT activity compared to controls. BAT thermogenesis is negatively associated with androgen levels in PCOS .