Influence of socio-demographic, clinical and functional factors on the severity of dementia

Dementia is one of the most relevant illnesses due to its functional impact on the elderly. The aim of the present study was to determine the influence of socio-demographic, clinical, cognitive and functional factors on the severity of dementia in elderly individuals. One hundred six elderly individuals with a diagnosis of dementia as determined by the DSM-IV/APA participated in the study. Cognition was assessed by the mini-mental state examination (MMSE); functional performance of basic and instrumental activities of daily living (BADLs and IADLs) was assessed by the Katz index (KI), Lawton-Brody index (LBI) and Pfeffer index (PI). The severity of dementia was established through the clinical dementia rating (CDR). In order to determine the influence of factors on the degree of dementia, ordinal regression analysis was performed. Age, MMSE, KI, LBI and PI scores had statistically significant associations to the severity of dementia. However, only the age (odds ratio (OR) = 0.197; confidence interval (CI) = 0.060-0.643) and performance in IADLs (LBI: OR = 1.237, CI = 1.077-1.422; PI: OR = 0.641, CI = 0.548-0.750) were maintained in the final ordinal regression model, R2 = 0.818. The results show that elderly individuals over 80 years of age and those with a more compromised performance in IADLs have a greater chance of exhibiting more severe degrees of dementia. These findings suggest that the ability to perform IADLs may be an important variable in differentiating degrees of the severity of dementia.