Cognitive impairment, dementia and quality of life in patients and caregivers.

OBJECTIVE To study the impact of cognitive impairment and severity of dementia on the quality of life (QoL) of patients and their caregivers. DESIGN Descriptive cross-sectional study within the NAtional Dementia Economic Study. SETTING 231 general practices and 15 specialist clinics in Belgium. SUBJECTS 605 patients aged > or = 65 years: 106 referent subjects without cognitive impairment (R), 113 subjects with cognitive impairment and no dementia (CIND), 386 subjects with mild (83), mild/moderate (108), moderate (62) or severe (133) dementia (D1 to D4). OUTCOME MEASURES QoL of patients: COOP/WONCA charts, Katz's Activities of Daily Living (ADL) scale, Lawton's Instrumental Activities of Daily Living (IADL) scale. QoL of caregivers: COOP/WONCA charts, SF-36 questionnaire, short-form Beck Depression Inventory, Sense of Competence questionnaire (SCQ). MAIN RESULTS QoL of patients: For R, CIND and D1 to D4 patients, dependence for ADL reached 5%, 6%, 16%, 20%, 48% and 79%, respectively, and mean IADL scores were 5.6, 5.0, 3.4, 2.0, 0.6 and 0.1, respectively. QoL of caregivers: The main impact of caregiving was on mental health, with SF-36 MCS scores of 51.3, 47.7 and 45.4 for R, CIND and all D patients and respectively 32.6%, 31.3% and 42.5% depression prevalence. Sense of competence decreased with severity of patient's cognitive impairment. Caregivers of CIND patients always rated intermediate between R and D1 patients. Caregivers of D3 patients were the most affected ones. CONCLUSION The data suggest that improving the cognitive status of patients and providing assistance to caregivers would be complementary ways of action to support caregiving of patients living at home.