Abstract
                 Background: Overweight and obesity are known to be associated with major health risks. Their detrimental effects on  central nervous system (CNS) have begun to be appreciated too. The data for cranial nerve involvement and CNS conduction  delays, however, are still sparse. Aims and Objectives: The study intended to assess the extent of influence by recording  pattern reversal visual evoked potential (PRVEP) and brainstem auditory evoked potential (BAEP) in overweight and  obese individuals. Materials and Methods: PRVEP and BAEP were recorded in 85 individuals (30 obese, 30 overweight,  and 25 controls) in the age group of 18-70 years. Indian-specific body mass index (BMI) cutoff points (controls: BMI  <23, overweight: BMI 23-25, and obese: BMI >25) were used for classifying the individuals. PRVEP P100 latency and  N75-P100 amplitude and BAEP absolute and interpeak latencies were compared among the three groups using one-way  ANOVA and Tukey’s multiple comparison tests. P < 0.05 was considered statistically significant. Results: Statistically  significant prolongation of PRVEP P100 latency (P < 0.01), BAEP absolute latency of wave III and V (P < 0.0001), and  interpeak latencies I-III and I-V (P < 0.001) was obtained in obese and overweight individuals as compared to the controls  with no significant alteration in N75-P100 amplitude among the three groups (P > 0.05). Conclusion: Overweight and  obesity document derangements in visual evoked potentials and BAEPs, indicating CNS conduction delays with brainstem  as well as cerebral cortical involvement. The influence of raised BMI (BMI >23) can affect the clinical interpretation of  these tests.