Low-grade systemic inflammation is associated with functional disability in elderly people affected by dementia

The decline in basic and instrumental activities of daily living (BADLs and IADLs, respectively) is a well-established clinical hallmark of dementia. Growing evidence has shown that systemic subclinical inflammation may be related to functional impairment. We evaluated the possible association between low-grade systemic inflammation and functional disability in older individuals affected by dementia. We explored the association between high-sensitivity C-reactive protein (hs-CRP) levels and BADLs/IADLs in older individuals affected by late onset Alzheimer's disease (LOAD; n 110), "mixed" dementia (n 135), or mild cognitive impairment (MCI; n 258), and compared them with 75 normal Controls. Independent of age, gender, comorbidity, and other potential confounders, higher hs-CRP was significantly associated with poorer BADLs (loss ≥ 1 function) in people with LOAD (odds ratio [OR] 3.14, 95% confidence interval [CI], 1.33-7.33) and mixed dementia (OR 2.48, 95%CI 1.12-5.55), but not in those with MCI (OR 1.38, 95%CI 0.83-2.45) or Controls (OR 2.98, 95%CI 0.54-10.10). No association emerged between hs-CRP and IADLs in any of the sub-group. Our data suggest that systemic low-grade inflammation may contribute to functional disability in older patients with dementia.