Autonomic dysfunction and resting heart rate abnormalities as early cardiovascular signals in polycystic ovary syndrome (PCOS): a focused review

Polycystic ovary syndrome (PCOS) is a common endocrine–metabolic condition that carries a higher cardiovascular risk than currently reflected by traditional screening tools. Emerging evidence suggests that resting tachycardia and autonomic dysfunction may serve as early, non-invasive indicators of cardiovascular dysregulation in this population. This review synthesizes current data on resting heart rate (RHR), heart rate variability (HRV), and direct autonomic markers in women with PCOS, drawing from human studies published between 2000 and 2025. Across 32 eligible studies, most reported increased sympathetic activity, reduced parasympathetic tone, elevated RHR, and impaired HRV patterns observed even in normal-weight or metabolically mild PCOS phenotypes. These alterations correlate with endothelial dysfunction, arterial stiffness, and subclinical atherosclerosis, underscoring their cardiovascular relevance. Mechanistic insights highlight the contributions of insulin resistance, hyperandrogenism, inflammation, adipokine imbalance, chemoreflex sensitization, and altered cortisol metabolism to autonomic disruption. Despite consistent findings, methodological variability in HRV protocols and inadequate adjustment for major confounders limit definitive interpretation. RHR, due to its simplicity and accessibility, including through wearable devices, holds promise as a supportive early risk signal; however, it should not be used in isolation. Future studies must adopt standardized autonomic measurements, including diverse cohorts, and evaluate whether modifying autonomic markers translates into improved cardiometabolic outcomes. Integrating RHR and HRV with metabolic and endocrine markers may enhance early cardiovascular risk stratification in women with PCOS.