Correlation between four cognitive tests and body mass index in mentally healthy subjects

Bulgarian Medical Journal, 2024, 18(1), 38-42.

K. Akabalieva

Department of Psychiatry and Medical Psychology, Faculty of Medicine, Medical University – Sofia

Abstract. Aim: To investigate the correlation between 4 cognitive tests and body mass index (BMI) in mentally healthy subjects in general and by gender, and to assess this relationship when education factor is controlled. Subjects and Methods: The sample consisted of 72 mentally healthy subjects (25 men, 47 women), for whom BMI was calculated, and the subjects were evaluated with 4 cognitive tests: Trail making test A (TMT-A), Trail making test B (TMT-B), Digit symbol test (DST), Verbal fluency test (VFT). Results were analyzed with descriptive statistics, Pearson correlation analysis, and the partial correlation method to control the influence of one factor on the correlation between two variables. Results: The two cognitive tests TMT-A and DST have a statistically significant correlation with BMI, and TMT-B approaches statistical significance. Lower cognitive results are associated with higher BMI values. This relationship remained statistically significant for TMT-A and DST when subject education was controlled. Conclusions: Mentally healthy subjects with higher BMI values showed statistically significant worse scores on three of the four cognitive tests. Education is a factor that affects cognitive functions.

Key words: cognition, Trail making test A and B, Digit symbol test, Verbal fluency test, BMI

Address for correspondence: Katerina Akabalieva, MD, е-mail: katerina_akabalieva@yahoo.com