Overweight or obese people with low levels of physical activity are a third more likely to develop cardiovascular disease, according to research published in the European Journal of Preventive Cardiology.
The observational study, which followed 5,000 people over the age of 55 for 15 years, categorised participants by BMI and levels of physical activity.
During the 15-year follow-up period, 16 per cent of participants had a cardiovascular event. It was found that, compared to people with a healthy weight and with high physical activity levels, obese people with high levels of physical activity were not at increased risk of cardiovascular disease.
However, obese people with low levels of physical activity were 1.35 times more likely to develop cardiovascular disease.
These results suggest that the benefits of physical activity may outweigh the impact of being overweight or obese on cardiovascular disease in middle-aged and elderly people.
The study’s lead author, Dr Klodian Dhana, said: ‘Overweight and obesity is associated with a higher risk of cardiovascular disease and it is recommended to lose weight. But in the elderly this is slightly different because weight loss, especially unintentional, is associated with muscle loss and death.
‘Physical activity is associated with a lower risk of cardiovascular disease regardless of age. We investigated the combined impact of body mass index (BMI) and physical activity on cardiovascular disease in the middle age to elderly population.
‘In the overall population we found that physical activity was protective for cardiovascular risk. Overweight and obese participants were not at increased cardiovascular risk compared to those of normal weight.
‘We do not refute the risk associated with obesity in the general population even though we did not find it in this older group. BMI may not be the best way to measure adiposity risk in the elderly.
‘Our results show that physical activity plays a crucial role in the health of middle age to elderly people. Those who are overweight and obese without adequate physical activity are at higher risk of developing cardiovascular disease.’
The measurement of BMI is constantly being questioned as an appropriate measure of obesity, and rightly so, as it doesn’t take into account body fat/muscle mass at all. This may not make a huge amount of difference to most people, but it can make the measurement misleading.
We should clearly be looking at more than just the BMI when thinking about cardiovascular health, and this study supports this, although it does have its drawbacks. It is an observational study, so relies on people self-reporting their data, which can obviously lead to inaccuracy. Besides stressing that physical activity is important for cardiovascular health, which we already know, the study doesn’t give us any new information to apply clinically.
We should still recommend healthy diets for multiple reasons beyond just cardiovascular health, and chances are that if an obese person engages in regular exercise and a healthy diet, they won’t be obese for much longer.
Research score: 2/5