HEART RATE VARIABILITY IN METABOLICALLY HEALTHY AND METABOLICALLY UNHEALTHY OBESE PREMENOPAUSAL WOMEN

Area of Science:

• Endocrinology
• Cardiology
• Autonomic Nervous System Research

Background:

• Metabolically healthy obese (MHO) individuals lack metabolic syndrome but the autonomic nervous system's role in their metabolic profile is understudied.
• Obesity is linked to metabolic dysfunction, and the autonomic nervous system (ANS) plays a key role in regulating physiological processes.

Purpose of the Study:

• To investigate heart rate variability (HRV) as a marker of autonomic nervous system (ANS) activity in metabolically healthy obese (MHO) versus metabolically unhealthy obese (MUO) premenopausal women.
• To determine if ANS activity differs between MHO and MUO women and how various metabolic health criteria influence these findings.

Main Methods:

• Analysis of heart rate variability (HRV) in 42 premenopausal women categorized as MHO or MUO.
• Metabolic profiles were assessed using Wildman, International Diabetes Federation (IDF), and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) criteria.
• Statistical adjustments were made for factors like systolic blood pressure, waist circumference, and HOMA-IR to analyze HRV parameters (e.g., RRNN, LF/HF, LF, SDNN, RMSSD, pNN50, HF, TP).

Main Results:

• No significant overall difference in HRV was observed between MHO and MUO women.
• Specific HRV parameters (RRNN, LF/HF) differed between groups when adjusted for systolic blood pressure (Wildman criteria).
• LF differed between groups when adjusted for waist circumference (IDF criteria), and several parameters (SDNN, RMSSD, pNN50, HF, TP) differed when adjusted for HOMA-IR.

Conclusions:

• The autonomic nervous system does not appear to be the primary driver of metabolic differences between MHO and MUO premenopausal women.
• Observed differences in HRV between MHO and MUO women are contingent upon the specific metabolic health criteria employed.
• Systolic blood pressure, HOMA-IR, and waist circumference significantly influence the HRV differences observed between MHO and MUO women.