Effects Of Age, Body Composition, And Inflammation On Cognitive Function In Females.

Abstract

PURPOSE: To investigate the correlation between individual parameters (age, body composition, and inflammation) and cognitive performance. METHOD: Fifty-six healthy women (age range: 20~60 yrs) were recruited and completed four cognitive tests, including attention, speedup test, Stroop tests (word, square, congruent, incongruent, and neutral conditions), and memory span test. All cognition tests were conducted in a counter-balanced order. Blood samples were collected to determine the ratio of neutrophil and lymphocyte (NLR) and the ratio of platelet and lymphocyte (PLR) which were considered as indicators of inflammation. The body composition was measured by using Dual Energy X-ray Absorptiometry. The correlation between age, body composition, inflammatory factors, and cognitive variables was analyzed by Pearson's correlation coefficient (r). P<0.05 was considered statistically significant. RESULTS: There were negative correlation between age and attention test (r=-0.47, p<0.005), Stroop tests (word: r=-0.65, p<0.001; square: r=-0.69, p<0.001; congruent: r=-0.61, p<0.001; incongruent: r=-0.70, p<0.001; neutral: r=-0.70, p<0.001). The results also showed that the higher the body fat % (BF%), the worse the cognitive test performance (attention test, r=0.46, p<0.005; Stroop's word tests, r=0.49, p<0.005; Stroop's square test, r=0.61, p<0.001; Stroop's congruent test, r=0.44, p<0.01; Stroop's incongruent, r=0.56, p<0.001; Stroop's neutral test, r=0.59, p<0.001). Similarly, the higher the body lean mass (BLM%), the better the cognitive test performance. There was positive correlation between age, NLR and PLR, but there was no significant correlation between inflammatory markers and cognitive performance. Furthermore, after controlled age, although the above net correlation was eliminated, the correlation between Stroop's square test and BF% (r=-0.343, p=0.035), square and BLM% (r=0.334, p=0.040), neutral test and BLM% (r=0.32, p=0.050) still exits. Besides, after controlled BF%, the age-related correlation effects are unchanged, and only the correlation between BLM% and the speed of answering represent significant (r=0.393, p<0.015). CONCLUSION: In addition to age, body fat is an important factor affecting cognitive performance. Supported by MOST 107-2410-H-845-018-MY3