The increased risk of heart failure was found in men who were within the normal body weight range (a body mass index of 18.5 to 25) in adolescence, with an increased risk starting in those with a BMI of 20 and rising steeply to a nearly ten-fold increased risk in those who were very obese, with a BMI of 35 or over, researchers said.
The study found that in men with a BMI of 20 and over, the risk of heart failure increased by 16 per cent with every BMI unit, after adjustments for factors that could affect the findings, they said.
“Although most studies define a normal weight as having a BMI between 18.5 and 25, this is probably not an appropriate definition in the young, most of whom are naturally thin” said Annika Rosengren from Sahlgrenska Academy in Sweden.
“This may be why we see an increase in the risk of heart failure starting at a fairly low BMI level. However, it was surprising to see the very steep increase in risk with increasing body weight above a BMI of 20,” said Rosengren.
“Given the global trend for growing numbers of teenagers to be overweight and obese, our findings suggest that heart failure, which in this study occurred at the relatively early average age of about 47 may well become a major threat to health worldwide,” she added.
Researchers analysed data on 1,610,437 men. They followed the men from the time they enlisted in the armed forces at 18, for between five to 42 years (an average follow-up time of 23 years)
During that time, 5,492 men were admitted to hospital for heart failure, with an average age at diagnosis of nearly 47.
Compared with men who had a BMI of between 18.5 and 20 at the time of enlistment, men with a BMI of 20 to 22.5 had a 22 per cent increased risk of heart failure, after adjusting for factors that could affect the results, researchers said.
The risk nearly doubled for those with a BMI between 22.5 and 25, and more than tripled for those with a BMI between 25 and 27.5, they said.
The risk increased more than six-fold for those classified as obese with a BMI between 30-35, and was nearly 10-fold for the very obese with a BMI of 35 or more, researchers said.
“Our findings show the importance of body weight in adolescence and suggest that more emphasis should be placed on the maintenance of a healthy body weight from an early age as a preventive measure,” said Rosengren.
The findings were published in the European Heart Journal.