Patients with underlying cardiovascular disease who don’t resume blood thinners early enough after gastrointestinal bleeding have a higher risk of major cardiovascular events and CVD-related death within a year, a study has revealed.

The INTERBLEED international prospective study, which included Australian haematologist Dr Paul Kruger among its authors, followed 3,814 adults to address the “considerable uncertainty” regarding long-term outcomes after a GI bleed.

Patients with CVD were recruited from 30 centres across nine countries, including Perth’s Fiona Stanley Hospital, in what has been the largest study to date specifically addressing the issue of antithrombotic resumption. Of the cohort, there were 1,612 who experienced a GI bleed and 2,202 without any GI bleeding history.

Findings published in Gastroenterology [link here] showed GI bleeding was independently associated with higher odds of all-cause death (OR 2.29), but not directly associated with cardiovascular events within 12 months of the bleed.

Instead, researchers found the lack of “relatively early resumption” of blood thinners drove poor outcomes. Resuming therapy within 4–7 days or 8–30 days of a bleed was associated with 63% lower odds of major adverse cardiovascular events (MACE) versus outright discontinuation or not resuming within 60 days.

However, ongoing use of blood thinners including during the bleeding event, resumption within 72 hours, and resumption of antithrombotic medications between 31 and 60 days did not reduce MACE odds.

Importantly, neither antithrombotic use nor early resumption was associated with higher odds of recurrent GI bleeding at 12 months, the researchers said.

Outcomes at 12 months for GI bleeding and non-bleeding patients:

• MACE occurred in 14.5% and 5.7%, respectively
• GI bleeds recurred in 8.6% and 1.6%, respectively
• Death from any cause occurred in 28.1% and 6%, respectively

The authors concluded that antithrombotic resumption following GI bleeding “should be the default approach” for most patients.

In more complex cases, they suggested that antithrombotic management should be discussed at multidisciplinary level immediately following the bleed with a clear plan and timeline in place for resumption.

“Firstly, appropriate and timely resumption of patients’ antithrombotic therapy following bleeding appear to be vital components of early management in this patient population, with our data showing a lower risk of MACE and CV-related death with resumption between 4 and 7 days,” they said.

“Secondly, given that a sobering 28% of CV patients who experienced GIB died within 12 months (compared to 6% of CV patients not experiencing GIB), it is clear that close follow-up is advised following bleeding events in this population, including efforts to optimise other risk factors we confirmed, including atrial fibrillation, diabetes, and arterial disease, among others.

“Though speculative, our results provide some potential mechanistic insight that thrombotic events related to antithrombotic interruption could be an important driver of adverse CV outcomes following GIB.”