[P4–558]: IMPACT OF ALZHEIMER's DISEASE DEVELOPMENT ON THE HEART: FOCUS ON INFLUENCE OF PHYSICAL AND MENTAL ACTIVITY AGAINST THE DELETERIOUS EFFECT OF SOCIAL ISOLATION AND PROTEIN MALNUTRITION

common analytic approach for accounting for spillover costs was to add informal caregiving time costs to patient costs (n1⁄432). Few studies included caregiver out-of-pocket costs in the analysis (n1⁄43). When spillover health effects were considered, most studies added informal caregivers’ QALYs to patient values (n1⁄410). Thirty three pairs of ICERs reported results with and without spillover effects. Incorporating spillover effects generally decreased ICERs (making them more favorable) (n1⁄416; 48%) or kept the intervention cost-saving (n1⁄413; 39%); and in fewer cases increased ICERs (n1⁄42; 6%) or produced no change (n1⁄42; 6%).Conclusions:Most dementia/AD CUAs incorporated spillover costs, often as time costs to a caregiver, but considered caregiver health impacts less often. Including spillover effects in analyses generally led to more favorable ICERs. The broader value of a dementia/AD intervention to society may be underestimated without considering these broader spillover effects.