Abdominal Obesity Could Up Risk of Recurrent Heart Attacks

Heart attack patients who have excess abdominal fat are more likely to have recurrent heart attacks, finds a new study conducted by researchers at Karolinska Institute in Stockholm, Sweden. The uniqueness of the new study is that it is the first to show that abdominal obesity increases the risk of recurrent heart attacks. This goes beyond previous studies, which had shown that abdominal obesity increases the risk of first-time heart attacks only.

The research findings have been published in the European Journal of Preventive Cardiology, which is the official journal of the European Society of Cardiology.

“Patients are typically put on a stringent medical treatment regimen after their first attack to prevent second events (called secondary prevention),” says lead author Dr. Hanieh Mohammadi of the Karolinska Institute, Stockholm, Sweden. “Secondary prevention works through reducing risk factors associated with a heart attack and stroke such as high blood sugar, lipids and blood pressure. It was previously unknown whether abdominal obesity is a risk factor for recurrent events among patients on secondary prevention treatments.”

Advertisement

Key Features of the Study

• Largest study ever conducted on the relationship between abdominal obesity and the risk of recurrent heart attacks
• 22,000 first-time heart attack patients were included in the study
• Patients were recruited from the nationwide SWEDEHEART Registry – a representative cohort of the entire Swedish population
• First study of its kind to analyze men and women together and separately
• Abdominal obesity was measured by waist circumference (WC)
• Cardiovascular events included fatal and non-fatal heart attacks and strokes
• Median follow-up period was 3.8 years

Advertisement

Key Findings of the Study

• 78 percent of men had abdominal obesity – WC ≥ 94 cm
• 90 percent of women had abdominal obesity – WC ≥ 80 cm
• Increasing abdominal obesity was independently associated with fatal and non-fatal heart attacks and strokes
• The above association was independent of secondary preventive treatments, as well as the following risk factors:
• Smoking
• Type-2 diabetes mellitus
• Hypertension (elevated blood pressure)
• Hyperlipidemia (elevated blood lipids)
• Body Mass Index (BMI)
• WC was a better marker of recurrent cardiovascular events than overall obesity
• Relationship between WC and recurrent cardiovascular events was stronger and more linear in the case of men
• Relationship curve for WC and recurrent cardiovascular events was U-shaped in case of women, i.e. mid-range WC was less risky compared to the lowest WC
• Mid-range WC for women was higher than the traditional cut-off for abdominal obesity (80 cm)

Mohammadi says: “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 atherosclerosis. 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 unrecognized,” she adds. “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.”

Advertisement

Reasons for Gender Differences in Abdominal Obesity and Cardiovascular Events

The research team is of the opinion that gender differences in abdominal obesity and propensity for cardiovascular events could arise from the fact that fat distribution in the body varies between men and women. In men, abdominal fat deposition is higher around vital organs (visceral fat), which can be harmful. However, in the case of women, abdominal fat deposition is predominantly subcutaneous, which is relatively harmless.

Limitations of the Study

The study included 3-times more men than women, which resulted in less statistical power in the female group. Therefore, further studies are warranted in order to unequivocally establish the accuracy of the data with reference to gender.

Concluding Remarks

Mohammadi concludes: “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. Maintaining a healthy waist circumference is important for preventing future heart attacks and strokes, regardless of how many drugs you may be taking or how healthy your blood tests are. Abdominal obesity can be tackled by eating a healthy and balanced diet and regular physical activity.”

Recommendation

The research team recommends that waist circumference should be used in clinical practice to identify first-time heart attack patients who are likely to be at a higher risk for further attacks.

Funding Source

The study was funded by the Janne Elgqvist Family Foundation and the Serafimer Laser Foundation, Sweden.

References:

1. Abdominal Obesity and the Risk of Recurrent Atherosclerotic Cardiovascular Disease after Myocardial Infarction - (https://doi.org/10.1177/2047487319898019)
2. Belly Fat Linked with Repeat Heart Attacks - (https://www.escardio.org/The-ESC/Press-Office/Press-releases/Belly-fat-linked-with-repeat-heart-attacks)

Source-Medindia