Informal Caregiver Time and Associated Cost in Patients with Alzheimer’S Disease in the United States (US): A Systematic Literature Review

OBJECTIVES: Alzheimer’s Disease (AD), a leading cause of dementia, is a progressive disease of the brain that results in significant social and economic costs to patients, caregivers, and society. The systematic literature review (SLR) aimed to identify studies conducted in the US evaluating the informal caregiver time and associated indirect costs (IC) in patients with AD.

METHODS: Embase^® and MEDLINE^® were searched for English language studies conducted in the US and published between Jan 2011 and Jan 2023, providing the informal caregiver time and associated IC. The SLR followed two review and quality control process as recommended by various HTAs.

RESULTS: Informal care is the time the caregiver spends on basic and instrumental Activities of Daily Living, supervision of AD patient, and lost production by the caregiver. The cost of informal care is considered an indirect cost. Of the five included studies, the median informal care time was 4.78 hours/day (range 0.97-10.82). The work productivity loss increased with AD severity and ranged between one day (mild AD) to 9.30 days (severe AD). Informal caregiver cost was reported as the main contributor to the total societal cost (>50%) incurred by community-dwelling AD patients, which increased with disease severity, i.e., highest in severe AD (£1,168 of £1,837, 63.5%) and lowest in mild AD group (£630 of £1,204, 52.3%). Similarly, a statistically significant increase in indirect informal care cost was observed with advanced severity, i.e., AD patients with mild dementia reported higher indirect costs than AD patients with mild cognitive impairment ($1,912 vs. $865, p<0.001).

CONCLUSIONS: Informal care provided by family and friends of elderly AD patients is unpaid and usually underestimated. The current research highlights the impact of informal care and its associated cost on the total societal burden of AD, which is immense and subsequently increases with AD severity.