Vascular risk factors are a major contributor to cognitive impairment and degenerative dementia in India

Abstract

AbstractBackgroundThe burden of vascular contribution to cognitive impairment and dementia is high in low and middle‐income countries (LMIC) like India. It is crucial to determine burden of vascular contribution to dementia in India, to develop effective preventive and treatment strategies. The aim of the study was to determine the prevalence of vascular risk factors across the spectrum of cognitive impairment and dementia in a large dementia cohort in South India.MethodPatients with cognitive impairment and dementia from the dementia registries of two University referral hospitals in South India were included. All patients underwent clinical, cognitive and imaging study and standard criteria were used to diagnose MCI, AD, FTD, VaD and mixed dementia. Vascular risk factor profile was determined in patients, and the presence of hypertension, diabetes, cardiac disease, stroke, smoking and chronic alcoholism were noted.ResultOf a total 1811 patients with cognitive impairment, 180 (9.9%) patients were diagnosed to have MCI, 517 (28.5%) AD, 205 (11.3%) FTD, 844 (46.6%) had VaD & 64 (3.5%) had mixed dementia. Overall, hypertension was the most prevalent vascular risk factor (62.7%) followed by stroke (46.6%). 35.5% of patients had diabetes mellitus(DM), 15.2% had chronic alcoholism, 14.4% were smokers and 14.2% had history of cardiac disorders.Hypertension was most commonly encountered in patients with AD (76.4%), followed by mixed Dementia (68.75%), VaD (63.4%), MCI (44.4%) and FTD (39.5%).DM was present in a high proportion of all subtypes of cognitive impairment and dementia (24.4% to 46.8%). The proportion of patients with stroke was highest in VaD (82.1%), but was also associated with one‐fourth of patients with AD and 15% of patients with mixed dementia. Frequency of smoking, chronic alcoholism and cardiac disease was highest in mixed dementia and VaD.ConclusionOur results demonstrate that a large burden of vascular risk factors exist in all forms of cognitive impairment and dementia in the Indian context. Hypertension and diabetes were found to be commonly associated with neurodegenerative dementia, in addition to vascular and mixed dementia. This large burden of vascular contribution represents needs and an opportunity to implement strategies to reduce burden of dementia in India and other LMICs