Age and efficacy of remote ischemic conditioning in acute ischemic stroke

Abstract Aims A post hoc analysis of RICAMIS trial to evaluate functional outcomes in relation to patient age. Methods Patients in RICAMIS were divided into six age groups. The primary outcome was excellent functional outcome at 90 days, defined as modified Rankin Scale (mRS) score of 0–1. Compared with patients receiving usual care alone, we investigated the association of remote ischemic conditioning (RIC) effect with functional outcomes in each group and the interaction between RIC effect and age. Results Of 1776 patients, 498 were assigned to <60 years, 326 to 60 to <65 years, 325 to 65 to <70 years, 278 to 70 to <75 years, 206 to 75 to <80 years, and 143 to ≥80 years. Higher proportions of primary outcome were found associated with RIC in <60 years group (72.6% vs. 64.8%; adjusted risk difference [RD], 6.8%; 95% CI, −1.6% to 15.1%; p = 0.11), 60 to <65 years group (70.7% vs. 67.1%; adjusted RD, 3.1%; 95% CI, −7.2% to 13.3%; p = 0.56), 65 to <70 years group (70.5% vs. 63.6%; adjusted RD, 3.5%; 95% CI, −6.8% to 13.8%; p = 0.51), 70 to <75 years group (59.7% vs. 54.9%; adjusted RD, 4.7%; 95% CI, −7.1% to 16.4%; p = 0.61), 75 to <80 years group (61.5% vs. 55.9%; adjusted RD, 5.7%; 95% CI, −7.8% to 19.1%; p = 0.41), and ≥ 80 years group (59.2% vs. 59.7%; adjusted RD, −2.6%; 95% CI, −18.8% to 13.5%; p = 0.75). No significant interaction between RIC effect and age was found among groups. Conclusions This is the first report that RIC effect may be attenuated with increasing age in patients with acute moderate ischemic stroke with respect to functional outcome.