Correlation between body mass index and autonomic function tests in medical students:  A cross-sectional observational study.

Dr. Amrutha  Kanagala; Dr. Ankur

doi:10.51168/sjhrafrica.v7i3.2380

Authors

Dr. Amrutha Kanagala Associate Professor, Department of Physiology, Mamata Medical College, Khammam, Telangana, India
Dr. Ankur Professor, Department of Physiology, Rohilkhand Medical College and Hospital, Bareilly, Uttar Pradesh, India

DOI:

https://doi.org/10.51168/sjhrafrica.v7i3.2380

Keywords:

Body mass index, Autonomic function tests, Medical students, Parasympathetic function, Blood pressure, Heart rate

Abstract

Background:

Overweight and obesity are increasingly common in young adults and are linked to early autonomic imbalance, a pathway that can precede later cardiometabolic disease.

Objectives:

To evaluate the association between body mass index (BMI) and standard autonomic function tests among medical students.

Methods:

This observational study was conducted in the Department of Physiology, Mamata Medical College, Khammam, Telangana, India, from January 2025 to December 2025. One hundred apparently healthy medical students underwent anthropometry, resting cardiovascular assessment, and autonomic function testing (deep breathing, Valsalva manoeuvre, and heart rate response to standing). Participants were classified as underweight, normal BMI, and overweight/obese. Group differences were tested using one-way analysis of variance, and BMI correlations were assessed using Pearson’s correlation.

Results:

Mean age was 21.3 ± 1.6 years, and mean BMI was 23.2 ± 3.6 kg/m²; 18% were underweight, 56% had normal BMI, and 26% were overweight/obese. Resting heart rate, systolic blood pressure, and diastolic blood pressure increased significantly across BMI categories [all p < 0.001]. Parasympathetic indices showed a significant decline with increasing BMI, including the E: I ratio, Valsalva ratio, and 30:15 ratio [all p < 0.001]. BMI correlated positively with resting heart rate, systolic blood pressure, and handgrip blood pressure response, and negatively with E: I ratio, Valsalva ratio, and 30:15 ratio [all p < 0.001].

Conclusion:

Higher BMI in medical students was associated with higher resting cardiovascular indices and lower parasympathetic reactivity on standard tests, suggesting early sympathovagal imbalance in overweight/obese participants.

Recommendations:

Routine BMI-based screening with brief autonomic assessment and targeted lifestyle counselling within medical colleges can support early risk reduction.

Author Biographies

Dr. Amrutha Kanagala, Associate Professor, Department of Physiology, Mamata Medical College, Khammam, Telangana, India

is an Associate Professor in the Department of Physiology at Mamata Medical College, Khammam, Telangana, India. She is actively involved in undergraduate and postgraduate teaching and contributes to competency-based medical education through academic mentoring and curriculum development. Her research interests span cardiovascular physiology, metabolic regulation, and applied clinical physiology, with a focus on translating basic physiological principles into clinical relevance. She has participated in institutional research projects and academic initiatives aimed at strengthening evidence-based medical education. ORCID iD: https://orcid.org/0009-0004-8413-2859

Dr. Ankur, Professor, Department of Physiology, Rohilkhand Medical College and Hospital, Bareilly, Uttar Pradesh, India

is a Professor in the Department of Physiology at Rohilkhand Medical College and Hospital, Bareilly, Uttar Pradesh, India. He has extensive experience in teaching physiology to undergraduate and postgraduate medical students and is actively engaged in academic administration and curriculum planning. His academic interests include cardiovascular and respiratory physiology, integrative human physiology, and medical education research. He has guided student research projects and contributes to institutional academic and faculty development activities, with a sustained focus on strengthening conceptual learning and clinical application of physiological principles.

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