Relation of Statin Use and Mortality in Community-dwelling Frail Older Patients with Coronary Artery Disease

Abstract Clinical decision-making for statin treatment in older patients with coronary artery disease (CAD) is under debate, particularly in community-dwelling frail individuals at high risk of death. In this retrospective observational study on 2,597 community-dwelling patients aged ≥65 years with a previous hospitalization for CAD, we estimated mortality risk assessed with the Multidimensional Prognostic Index (MPI), based on the Standardized Multidimensional Assessment Schedule for Adults and Aged Persons (SVaMA), used to determine accessibility to homecare services/nursing home admission in 2005-2013 in the Padova Health District, Veneto, Italy. Participants were categorized as having mild (MPI-SVaMA-1), moderate (MPI-SVaMA-2), and high (MPI-SVaMA-3) baseline mortality risk, and propensity score (PS)-adjusted hazard ratios (HRs) of three-year mortality were calculated according to statin treatment in these subgroups. Higher MPI-SVaMA scores were associated with lower rates of statin treatment and higher three-year mortality (MPI-SVaMA-1=23.4%; MPI-SVaMA-2=39.1%; MPI-SVaMA-3=76.2%). After adjusting for PS quintiles, statin treatment was associated with lower three-year mortality risk irrespective of MPI-SVaMA group [HRs (95% confidence intervals, CI):0.45 (0.37-0.55), 0.44 (0.36-0.53), and 0.28 (0.21-0.39) in MPI-SVaMA-1, -2, and -3 groups, respectively (interaction test p=0.202)]. Subgroup analyses showed that statin treatment was also beneficial irrespective of age [HRs (95% CI):0.38 (0.27-0.53), 0.45 (0.38-0.54), and 0.44 (0.37-0.54) in 65-74, 75-84, and ≥85 year-old groups, respectively (interaction test p=0.597)]. In conclusion, in community-dwelling frail older patients with CAD, statin treatment was significantly associated with reduced three-year mortality irrespective of age and multidimensional impairment, although the frailest patients were less likely to be treated with statins.