White blood cell count is associated with some features of metabolic syndrome in a very old population

Although the association between white blood cell (WBC) counts and the risk of cardiovascular disease has been repeatedly described, its biological mechanism is still unclear. A significant correlation has been demonstrated in adults between WBC counts and some risk factors for coronary heart disease (CHD), including insulin resistance. The aims of this study were: 1) to investigate the association between WBC count and some risk factors for atherosclerosis in a sample of octo-nonagenarians; and 2) to test the hypothesis of an association between WBC count and "metabolic syndrome", a clinical condition mediated by insulin resistance.

The study involved 160 free-living healthy octo-nonagenarians participating in the Val Vibrata Aging Project, whose WBC count, and anthropometric and metabolic parameters were measured using standardised methods. WBC count correlated positively with the logarithm of triglyceride, apoprotein B and glucose levels, and negatively with high-density lipoprotein cholesterol: the subjects with low high-density lipoprotein and high triglyceride levels had higher WBC count than normal subjects. The WBC count were significantly higher in the subjects with four or more of six features of metabolic syndrome than in those with three or less.

The results of this study support the existence of a significant association between WBC count and some of the typical features of metabolic syndrome in very old subjects.