Doctor factor significant in weight loss

OVERWEIGHT patients could be motivated to lose weight if their doctors broached the subject and set clear weight loss targets for them, according to Australian experts.

A study in the American Heart Journal has shown a physician diagnosis of overweight status was a significant predictor of attempted and successful weight loss.(1)

It showed diagnosing a patient as being overweight not only helped the patient recognise they were overweight but was also predictive of the patient wanting and attempting weight loss, and actually succeeding in losing weight in a 12-month period.

Yet, among the 907 patients with cardiovascular disease and central obesity in this study, only 62% reported that they had previously been informed by a physician that they were overweight.

Associate Professor Roger Allan, clinical cardiologist at Prince of Wales Hospital in Sydney, said doctors should address the issue of weight loss in all overweight patients and give them goals to strive for.

Professor Allan said there were barriers to doctors mentioning weight, which include trying to preserve a good relationship with the patient.

“To make people lose weight is such a challenge that to mention it means you have taken on the responsibility to try to do something about it and I suspect there may be that psychological barrier to talking about it.”

He said doctors should tell patients they want to see them again in 3 months’ time and “I want you to be three kilograms lighter”.

This type of encouragement should be ongoing and could include suggestions for long-term changes in their diet, including modification of carbohydrate intake and smaller portions, and encouraging daily walking, he said.

In the study, which used data from the US National Health and Nutrition Examination Survey (NHANES) 1999 to 2004, central obesity was defined as waist circumference of 102 cm or more in men and 88 cm or more in women. Success was defined as 5% or more weight loss in the preceding year.

The results showed 78% of respondents were aware of their overweight status and 80% wanted to weigh less.

Despite this awareness and desire, only 49% of centrally obese adults had attempted weight loss in the previous year.

People who had been informed by physicians of their overweight status were almost three times as likely to successfully lose weight.

Professor Ian Caterson, director of the Boden Institute of Obesity, Nutrition, Exercise and Eating Disorders at the University of Sydney, agreed there were several barriers to doctors mentioning weight with patients, despite the fact overweight and obesity were common.

“We feel uncomfortable, we feel we don’t really have much to offer … and it’s very difficult to do and takes time, and there is also the commercial imperative because you are bit worried about upsetting somebody and having them go down the road,” he said.

“We happily write prescriptions for antihypertensives and oral hypoglycaemics and statins, and that’s easy, but we have got to get better at lifestyle management,” Professor Caterson said.

Dr Andrew Binns, a NSW GP with an interest in lifestyle medicine, said the emphasis should be on an overall lifestyle approach to keep the heart healthy, whether the patient was overweight or not.

“Even if someone is unable to lose weight, which is common among [people with type 2 diabetes], then improving diet and increasing activity levels can have metabolic benefits and [bring about] CVD risk reduction without weight loss,” he said.

A study published in the New England Journal of Medicine last week showed patients were more likely to stick to a diet and maintain weight loss if their diet included a modest increase in protein content and a modest reduction in the glycaemic index.(2)

1. Am Heart J 2010; 160: 934-942.

2. N Engl J Med 2010; 363: 2102-2113.

Posted 29 November 2010