Sex Differences in Hemodynamic and Autonomic Reactivity during Cold Pressor Test in Chronic Kidney Disease

Abstract

Introduction: Chronic kidney disease (CKD) is characterized by sympathetic nervous system (SNS) overactivity that contributes to increased cardiovascular risk. Hemodynamic reactivity during the cold pressor test (CPT) has been widely used to evaluate sympathetic neural control in patient populations, and increased neurocardiovascular reactivity to CPT has been shown to predict greater risk of future cardiovascular events. Prior studies have suggested that males with CKD have higher long-term cardiovascular disease risk compared to females with CKD; however, whether sex differences in neurocardiovascular responsivity during CPT exists within CKD remains unknown. Objectives: Our primary objective was to evaluate potential sex differences in hemodynamic and autonomic reactivity during CPT in patients with CKD. Hypothesis: Males with CKD have an augmented pressor and sympathetic response to sympathoexcitation induced by CPT compared with females with CKD. Methods: Patients with CKD (Stage III and IV) with stable renal function were included. Continuous beat to beat blood pressure (BP), heart rate (HR) and muscle sympathetic nerve activity (MSNA) by microneurography were measured at rest for 10 minutes and during CPT that consisted of immersion of the hand to the wrist in ice water (4–5 °C) for one minute, followed by a 5-min recovery period. Results: 25 participants with CKD were included (N= 14 male, N=11 female). There were no differences in baseline characteristics, resting hemodynamics or MSNA between male and female groups. Males with CKD had a steeper rate of increase and higher peak levels of diastolic BP (DBP, 101±3 vs 87±3; p=0.008) and mean arterial BP (MAP, 130±4 vs 112±5 mm Hg, p=0.023) during CPT compared to females with CKD, respectively. Conversely, females with CKD had a steeper rate of increase in HR during CPT compared to males. MSNA increased in both males and females during CPT; however, there was no difference in MSNA reactivity during CPT between groups. Conclusions: Males with CKD had greater BP reactivity during CPT compared to females with CKD, while females with CKD had greater HR reactivity during CPT compared to males. There was no difference in sympathetic reactivity between groups. Augmented BP reactivity during CPT in males with CKD may contribute to sex differences in cardiovascular disease risk in patients with CKD. Supported by NIH Grants R33AT010457 and R01HL135183. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.