Is total lymphocyte count related to nutritional markers in hospitalized older adults?

- Older patients are commonly malnourished during hospital stay, and a high prevalence of malnutrition is found in hospitalized patients aged more than 65 years.

- To investigate whether total lymphocyte count is related to other nutritional markers in hospitalized older adults.

- Hospitalized older adults (N=131) were recruited for a cross-sectional study. Their nutritional status was assessed by the Nutritional Risk Screening (NRS), anthropometry, and total lymphocyte count. The statistical analyses included the chi-square test, Fisher's exact test, and Mann-Whitney test. Spearman's linear correlation coefficient determined whether total lymphocyte count was correlated with the nutritional markers. Multiple linear regression determined the parameters associated with lymphocyte count. The significance level was set at 5%.

- According to the NRS, 41.2% of the patients were at nutritional risk, and 36% had mild or moderate depletion according to total lymphocyte count. Total lymphocyte count was weakly correlated with mid-upper arm circumference (r=0.20507); triceps skinfold thickness (r=0.29036), and length of hospital stay (r= -0.21518). Total lymphocyte count in different NRS categories differed significantly: older adults who were not at nutritional risk had higher mean and median total lymphocyte count (P=0.0245). Multiple regression analysis showed that higher lymphocyte counts were associated with higher triceps skinfold thicknesses and no nutritional risk according to the NRS.

- Total lymphocyte count was correlated with mid-upper arm circumference, triceps skinfold thickness, and nutritional risk according to the NRS. In multiple regression the combined factors that remained associated with lymphocyte count were NRS and triceps skinfold thickness. Therefore, total lymphocyte count may be considered a nutritional marker. Other studies should confirm these findings.