“Abdominal obesity not only increases your risk for a first heart attack or stroke, but also the risk for recurrent events after the first misfortune,” said study author Hanieh Mohammadi from the Karolinska Institute in Sweden.
Prior studies have shown that abdominal obesity is an important risk factor for having a first heart attack. But until now, the association between abdominal obesity and the risk of a subsequent heart attack or stroke was unknown.
The research, published in the European Journal of Preventive Cardiology, followed more than 22,000 patients after their first heart attack and investigated the relation between abdominal obesity (measured by waist circumference) and the risk for recurrent cardiovascular disease events.
The researchers specifically looked at events caused by clogged arteries, such as fatal and non-fatal heart attack and stroke. Patients were recruited from the nationwide SWEDEHEART registry and followed for a median of 3.8 years. Most patients — 78 percent of men and 90 percent of women — had abdominal obesity (waist circumference 94 cm or above for men and 80 cm or above for women).
Increasing abdominal obesity was independently associated with fatal and non-fatal heart attacks and strokes, regardless of other risk factors (such as smoking, diabetes, hypertension, blood pressure, blood lipids and body mass index [BMI]) and secondary prevention treatments.
According to the researchers, waist circumference was a more important marker of recurrent events than overall obesity. The reason abdominal obesity is very common in patients with a first heart attack is that it is closely linked with conditions that accelerate the clogging of arteries through atherosclerosi, the researchers said. These conditions include increased blood pressure, high blood sugar and insulin resistance (diabetes) as well as raised blood lipid levels.
“Our results, however, suggest that there may be other negative mechanisms associated with abdominal obesity that are independent of these risk factors and remain unrecognised,” Mohammadi said. “In our study, patients with increasing levels of abdominal obesity still had a raised risk for recurrent events despite being on therapies that lower traditional risk factors connected with abdominal obesity such as anti-hypertensives, diabetes medication and lipid lowering drugs.”
According to the study, the relationship between waist circumference and recurrent events was stronger and more linear in men. “There were three times as many men in the study compared to women, contributing to less statistical power in the female group. Therefore, more studies are needed before definite conclusions can be drawn according to gender,” Mohammadi noted.