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Antiplatelet therapy ( APT ) is associated with increased risk of intracerebral hemorrhage ( ICH ), though data about the association between APT use and mortality risk after ICH are limited .

In a study published in Stroke , Nadeem I . Khan , MD , from the Department of Neurology at the Southern Illinois University School of Medicine in Springfield , and coauthors assessed mortality and other post-ICH outcomes associated with prior APT use in patients with ICH in a real-world setting . They found that patients who received combination APT – but not single APT – at the time of ICH diagnosis had a higher mortality risk , compared with patients who were not receiving APT .

“ These findings provide important insights into the risks associated with prior APT use among … patients with ICH ,” the authors wrote , adding that the results suggest “ a threshold effect ” in which platelet-function inhibition affects outcome .

The investigators identified 82,576 patients not on oral anticoagulant therapy from 1,574 sites from the Get With The Guidelines ® -Stroke registry database – an ongoing , voluntary , continuous registry and performance-improvement initiative for stroke care – between October 2012 and March 2016 . Prior to ICH diagnosis , patients were :

• not receiving APT ( n = 54,299 ; 65.8 %)

• receiving single APT ( n = 24,331 ; 29.5 %)

• receiving combination APT ( n = 3,946 ; 4.8 %)

The median age of patients not receiving APT was 64 years , and it was 76 years in the single- and combination-APT groups ( ranges not provided ). The most common APT used in the single-APT group was aspirin .

The researchers detected a modest increase in in-hospital mortality in patients who were receiving APT , compared with those who were not ( 24 % vs . 23 %; odds ratio [ OR ] = 1.05 ; 95 % CI 1.01-1.10 ; p = 0.012 ).

Between patients in the singleand combination-APT groups , the risk of in-hospital mortality was higher in the combination group ( 23 % and 30 %, respectively ). See TABLE 1 for more outcomes .

The researchers found no statistically significant difference in in-hospital mortality among patients who were not on any APT , compared with those on single APT , but mortality was higher among patients receiving combination APT , compared with no APT ( OR = 1.5 ; 95 % CI 1.39-1.63 ). This association

— NADEEM I . KHAN , MD persisted even after the researchers adjusted for the National Institutes of Health Stroke Scale score ( OR = 1.49 ; 95 % CI 1.33-1.67 ; p < 0.0001 ). See TABLE 2 for more outcomes .

The authors noted that future trials should evaluate whether patients with ICH on combination APT would benefit from restoring platelet function .

The study is limited by its

TABLE 1 . Outcomes Based on Single Versus Combination APT

Variable

All Patients Receiving APT ( n = 28,277 )

In-hospital mortality 6,848 ( 24.2 %)

In-hospital mortality or hospice care

9,854 ( 34.9 %)

Discharged home 6,276 ( 22.2 %)

Length of stay , days 27 336

Independent ambulation at discharge

Modified Rankin score at discharge , > 2

APT = antiplatelet therapy

5,878 ( 23.1 %)

14 725 ( 85.8 %)

Single APT ( n = 24,331 )

5,645 ( 23.3 %)

8,259 ( 33.9 %)

5,481 ( 22.5 %)

23 563

5,145 ( 23.5 %)

12 565 ( 85.5 %)

TABLE 2 . Association Between Previous APT Use and Outcomes

retrospective design . Missing data , including patients ’ comorbidity scores , may also have had a confounding effect on the study results .

The authors report research funding from Boehringer Ingelheim , Portola , Pfizer , and CSL Behring .

REFERENCE

Khan NI , Siddiqui FM , Goldstein JN , et al . Association between previous use of antiplatelet therapy and intracerebral hemorrhage outcomes . Stroke . 2017 ; 48:1810-7 .

Combination APT ( n = 3,946 )

1,203 ( 30.5 %)

1,603 ( 40.6 %)

795 ( 20.2 %)

3,773

733 ( 20.6 %)

2,160 ( 87.5 %)

Combination APT

1.48 ( 95 % CI 1.37-1.58

In-hospital mortality or discharged to hospice

Single APT 1.13 ( 95 % CI 1.10-1.17 )

Combination APT

APT = antiplatelet therapy

1.51 ( 95 % CI 1.41-1.62 )

< 0.0001 1.50 ( 95 % CI 1.39-1.63 )

< 0.0001 0.99 ( 95 % CI 0.95-1.03 )

< 0.0001 1.32 ( 95 % CI 1.23-1.42 )

< 0.0001 1.49 ( 95 % CI 1.33-1.67 )

0.5046 1.04 ( 95 % CI 0.98-1.10 )

< 0.0001 1.33 ( 95 % CI 1.19-1.49 )

< 0.0001

0.2041

< 0.0001

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