Both index and high body fat increased lean mass independently predicted better survival in patients with stable heart disease, according to a new report in the Journal of the American College of Cardiology.
The study provides further evidence for the “obesity paradox”: while patients with a high body mass index (BMI) are at greater risk for heart disease, the patient overweight and obese people with heart disease a better prognosis than patients skinny.
Dr Carl J Lavie, an associate professor at the Ochsner Clinical School of the University of Queensland School of Medicine in New Orleans and the first author of the new study, said that patients were more likely to develop heart disease lean due to genetic predisposition, while obese patients develop heart disease as a result of they are overweight. “This is not possible if we make people fat it protects them, it is possible that they got their heart disease for different reasons,” he said.
How to research conducted
Most studies show obesity paradox rely on BMI, which is not always the best indicator of body fatness, Dr. Lavie and his team note in their report. To solve this problem, find them in the percentage of body fat and lean mass index (LMI) and survival in 570 consecutive patients referred for cardiac rehabilitation. At three years of follow up, 26 patients died.
Each patient was classified as a low or high body fat (BF) and LMI low or high. There were 62 patients with low BF and low BMI, 53 with high and low BF LMI, 179 with low and high BF LMI, and 276 with high BF and high LMI.
Survival was worst for BF / low low BMI group, 15% died during follow-up, and best for BF / LMI-high group, which has a mortality rate of 2.2% .
Mortality was 5.7% for BF high / low LMI group and 4.5% for BF / low height LMI.
The results were similar for men and women.
Patients with chronic obstructive pulmonary disease (COPD) have a very high mortality rate, at 18.5%, compared to 3.9% for patients without COPD. However, when the researchers adjusted for COPD in the multivariate analysis, they found that it was independently predict death. Accounting for COPD “modestly lower” LMI effect on mortality, but it did not affect the influence of BF.
High body fat and a better prognosis?
“Any time you have a high lean mass you usually have good things happen here,” says Dr. Lavie. “What I think is more surprising that high body fat is associated with a better prognosis.”
“We certainly do not want to give people the idea that it is better to be fat,” Dr. Lavie. One of the messages that can be brought home from the doctor’s findings, he said, is to advise their patients to build their lean mass by eating well and getting enough exercise, including training strength.