Obese cardiac patients are less likely to die than their normal weight counterparts, say researchers.

研究人员称，身体肥胖的心脏病患者比正常体重患者有较小的死亡几率。

This is despite them reporting worse health and being less likely to follow lifestyle advice, a study of more than 4,400 patients reported.

One explanation is that doctors treat the disease more aggressively, the University College London team said.

The British Heart Foundation also said that where people stored fat, not just general obesity, was important.

It is not the first time researchers have pointed out this paradox, that being overweight or obese - a risk factor for heart disease in itself - can actually lead to a better prognosis（预知）.

One theory has been that maybe such patients were fitter, despite their size - taking more exercise for example.

To see if this was the case, researchers from University College London looked at data from patients who took part in the Health Survey for England or Scottish Health Survey.

They found that, as with other studies, patients with cardiovascular disease who were obese or overweight were less likely to die over the next seven years than people of a normal weight who had the condition.

In all 31% of patients were obese - that is with a body mass index of 30 or more - they reported in Preventive Medicine.

Those patients tended to be younger but reported worse health and had more heart risk factors such as raised cholesterol（胆固醇） and blood pressure, but were less likely to smoke.

The researchers found that those who took part in physical activity at least once a week and did not smoke had a lower risk of death whatever their weight.

But obese patients who did not stick to these healthy lifestyle recommendations still had a lower risk of death than normal weight patients who smoked or were inactive.