Correlation between body mass index and visual reaction time among obese and non-obese young adults attending a tertiary care academic hospital: A cross-sectional study.

BACKGROUND: Reaction time is an important indicator of psychomotor performance and central nervous system efficiency. Obesity has been associated with various metabolic and cardiovascular complications; however, its relationship with basic psychomotor functions such as visual reaction time remains inadequately explored, particularly among young adults. AIM: To evaluate the correlation between body mass index (BMI) and visual reaction time (VRT) in young adults. MATERIALS AND METHODS: This prospective cross-sectional analytical study was conducted among 385 apparently healthy adults aged 18-35 years. Body mass index was calculated using standard anthropometric measurements, and participants were categorised into BMI groups based on WHO criteria. Visual reaction time was assessed using an audio-visual reaction time apparatus. Normality was assessed using the Shapiro-Wilk test, and Spearman's rank correlation was used for statistical analysis. RESULTS: A statistically significant positive correlation between BMI and visual reaction time was observed among obese participants (ρ = 0.314, p < 0.001). Obese individuals exhibited a median visual reaction time of 268 ms compared to 232 ms in normal-weight participants - a 36 ms (15.5%) prolongation. CONCLUSION: Higher BMI was associated with prolonged visual reaction time among obese young adults, suggesting early changes in psychomotor performance related to obesity. Visual reaction time may serve as a simple, non-invasive tool to detect subtle neurofunctional changes associated with increased adiposity.