Using machine learning, researchers at Karolinska Institutet have identified eight primary factors that increase the risk of a common bleeding complication after heart attack.
Some of these factors had been known already, however, the researchers have found additional predictors, such as smoking, blood pressure and blood glucose. The study was published in the European Heart Journal – Cardiovascular Pharmacotherapy.
“If we can identify patients at high risk of upper gastrointestinal bleeding following heart attack, doctors will be able to take prophylactic measures to mitigate this risk,” said the study’s corresponding author Moa Simonsson, deputy consultant at Karolinska University Hospital and doctoral student. “There are, for instance, drugs that combat bleeding complications, gut bacteria tests that can be used on risk groups and other possibilities for personalised treatment for heart attack patients at high risk of bleeding complications.”
Upper gastrointestinal (GI) tract bleeding is one of the most common bleeding complications following acute myocardial infarction. The condition requires a lot of resources to treat, causes considerable suffering and increases mortality risk. Bleeding complications also limit antithrombotic use, which in turn can worsen the cardiovascular prognosis.
Over the past 20 years, a close focus on bleeding has resulted in several strategies for reducing the risk of upper gastrointestinal tract bleeding. However, few studies on this complication include a diverse population of heart attack patients.
For the current study, the researchers sourced data from the national SWEDEHEART registry on almost 150 000 patients with acute myocardial infarction between 2007 and 2016. Approximately 1.5 percent of these patients suffered GI bleeding within a year of their heart attack, and they also had an increased risk of death and stroke.
Several known factors that increase the risk of upper GI tract bleeding were confirmed by the analysis, including low levels of haemoglobin, previous upper GI tract bleeding, age and intensive antithrombotic treatment.
Using an algorithm, the researchers also identified additional risk factors, including smoking, blood pressure, blood glucose and previous treatment for stomach disorders, such as ulcers and acid reflux.
“If you combine traditional statistical models with machine learning methods, you can create unique opportunities to find key risk factors for previously unknown cardiovascular events,” explained co-author Philip Sarajlic, doctoral student at Karolinska Institutet. “This makes it possible for us to make effective use of valuable data from the medical quality registry by taking account of complex relationships between risk factors and outcomes in order to further optimise the current recommendations for patient care.”
The researchers will soon begin a major clinical study to explore the significance of diagnosis and treatment of a common infection in the upper GI tract.
“A pilot study last year showed a two-fold increase in the presence of Helicobacter Pylori in heart attack patients,” said last author Robin Hofmann, researcher and consultant at Karolinska Institutet. “We will now proceed with a large randomized study to ascertain whether a systematic screening of heart attack patients for Hp infection and, where relevant, its treatment, can reduce bleeding complications and improve prognosis after heart attack.”
Source: Karolinska Institute
