To compare outcomes and complications of long-term current use of DAPT versus ASA monotherapy versus no-antiplatelets drug in acute ischemic stroke (AIS) management.

Multiple trials such as SPS3, MATCH, CHANCE, and POINT etc. have evaluated dual antiplatelet therapy(DAPT) over Aspirin(ASA) monotherapy for recurrent ischemic stroke prevention. Considering the effect size; large nationwide studies might better assess outcomes, its association and fill the gaps in existing knowledge.

A population-based retrospective cross-sectional study of Nationwide Inpatient Sample(years2003-2014) in adult(>18-years) AIS hospitalizations was performed to identify patients taking DAPT and ASA on admission using ICD-9-CM code. The univariate analysis was performed using the chi-square test and  multivariable survey logistic regression analyses were performed to compare outcomes[mortality, morbidity(hospital stay>5days-90 percentile of mean and transfer to short-term hospital/skilled nursing facility/home health care), discharge(home vs. no-home), APRDRG severity/loss of function, and risk of death] and major complications [hemorrhagic transformation(HT) and upper gastrointestinal bleeding(UGIB)].

Out of 4,224,924 AIS hospitalizations, 52,274(1.24%) and 311,777(7.38%) were on DAPT and ASA respectively. Long-term/current DAPT and ASA use were associated with lower prevalence of mortality(2.17%vs.3.14%vs.5.41%), morbidity(3.80%vs.3.91%vs.7.61%), discharge to non-home(58.86%vs.58.78%vs.62.86%), loss of function(34.70%vs.34.31%vs.37.14%), and risk of death(20.17%vs.19.89%vs.21.35%).(p<0.0001) compared to non-user. On weighted regression analysis, DAPT and ASA use were associated with lower odds of mortality(DAPT-aOR:0.45; 95%CI:0.39-0.51; ASA-aOR:0.61; 95%CI:0.58-0.64), morbidity(DAPT-aOR:0.54; 95%CI:0.49-0.61; ASA-aOR:0.56; 95%CI:0.54-0.59), discharge to non-home (DAPT-aOR:0.78; 95%CI:0.75-0.82; ASA-aOR:0.80; 95%CI:0.79-0.82), loss of function (DAPT-aOR:0.76; 95%CI:0.73-0.80; ASA-aOR:0.80; 95%CI:0.78-0.82), risk of death (DAPT-aOR:0.77; 95%CI:0.73-0.82; ASA-aOR:0.82; 95%CI:0.80-0.84), and UGIB (DAPT-aOR:0.52; 95%CI:0.35-0.79; ASA-0.59; 95%CI:0.50-0.69) compared to non-users. Neither DAPT nor ASA use was significantly associated with HT (DAPT-aOR:1.07; 95%CI:0.91-1.25; ASA-aOR:1.04; 95%CI:0.97-1.11).

In this large nationwide study, outcomes for AIS with long-term use of DAPT was found to be superior than ASA monotherapy or no-antiplatelet therapy. Unlike prior understanding, our study showed no significant difference in terms of major complications. Large prospective studies are required to validate these findings.