White blood cell count and psychomotor cognitive performance in the elderly

• Published in: European journal of clinical investigation 2011-05, Vol.41 (5), p.513-520
• Main Authors: Kao, Tung-Wei, Chang, Yaw-Wen, Chou, Chih-Chieh, Hu, Jung, Yu, Yau-Hua, Kuo, Hsu-Ko
• Format: Article
• Language: English
• Subjects: Aged; Biological and medical sciences; Cognition; Cross-Sectional Studies; elderly; Female; General aspects; Humans; Leukocyte Count - statistics & numerical data; Male; Medical sciences; Psychomotor Performance; Regression Analysis; white blood cell
• ISSN: 0014-2972; 1365-2362
• DOI: 10.1111/j.1365-2362.2010.02438.x

Eur J Clin Invest 2011; 41 (5): 513–520 Background  White blood cell (WBC) count is associated with many inflammatory diseases such as cardiovascular disease, diabetes and hypertension. Research on the relationship of WBC count and cognition in the elderly is relatively sparse. This study examined the association between WBC count and cognitive performance in older adults. Methods  Data from the National Health and Nutrition Examination Survey (1999–2002) containing 1670 older adults were analysed. Every subject completed a household interview, examination of digit symbol substitution test (DSST) scores, WBC count measurement and a questionnaire regarding personal health. WBC count was restricted to the normal range and divided into quartiles, using a multiple hierarchical regression model to estimate the relationship between WBC counts and DSST scores. Quartile‐based analysis with an extended‐model approach was used for further covariates adjustment. Trends test examining the associations across increasing quartiles of WBC counts and DSST scores were also conducted. Results  In the multiple hierarchical regression model, the β coefficient, representing the change of DSST scores for each 1000 cells uL−1 increase in WBC count, was −0·097 (R2 = 0·343, P