TORONTO (Canadian Press) -- A new report says Canadians aged 50-plus who are diagnosed with a chronic condition like heart disease or diabetes rarely make lifestyle changes that could extend their lives.

The Statistics Canada study found quitting smoking or cutting back on cigarettes were the changes most commonly reported, but most tobacco users continued to smoke.

People diagnosed with diabetes were the most likely to make changes, although the lifestyle improvements were still modest.

The 12-year study of more than 17,000 Canadians found those diagnosed with diabetes reduced smoking, drank less alcohol, exercised more, and ate more fruit and vegetables.

But those who developed a respiratory disease like asthma or emphysema reported little change in smoking behaviour or eating habits, and they also became less physically active.

The study found a reduction in excessive drinking was the only change in health behaviours by people with a respiratory disease.

Heart disease, cancer, stroke, respiratory disease and diabetes are among the leading causes of death in Canada. Worldwide, these chronic conditions account for 60 per cent of all deaths, but are considered largely preventable with improved lifestyle behaviours.

"For people with a chronic illness, adopting a healthier lifestyle, such as smoking cessation, increased physical activity, eliminating heavy alcohol consumption and improving diet, can extend longevity ... and enhance quality of life," the authors write.

(c) The Canadian Press, 2012