Increased C-reactive protein is not associated with apathy: the Leiden 85-Plus Study

Background Apathy has recently been recognized as a distinct clinical syndrome although it is difficult to differentiate from late life depression. In old age, apathy as a syndrome in itself and depression may have different etiologies. Inflammatory markers have been associated with depression in the elderly, but the relation with apathy is unknown. Objective To assess the relation between C‐reactive protein (CRP) and apathy as a syndrome in itself, apart from depression, in subjects aged 85 and older. Methods All data come from the Leiden 85‐Plus Study, a prospective, population‐based study of 599 elderly subjects. CRP was measured at baseline. In all subjects with a Mini Mental State Examination (MMSE) ≥19 points (n = 500), apathy and depression were assessed annually from age 85 to 90 using the three apathy and twelve depression questions of the 15‐item Geriatric Depression Scale (GDS‐15). The association between CRP and apathy or depressive symptoms was assessed both at baseline and longitudinally. Results At baseline, no association was found between CRP‐concentration and apathy or depression. In subjects free of apathy and depression at baseline, subjects in the highest CRP‐tertile at baseline had significantly more increase in depressive symptoms but not in apathy symptoms during follow‐up. Conclusion Higher CRP concentrations increased the risk of depression but not apathy in a community‐based cohort of 85 years old subjects. This suggests that apathy and depression in old age have different etiologies. Copyright © 2009 John Wiley & Sons, Ltd.