Synopsis of the 2006 Canadian clinical practice guidelines on the management and prevention of obesity in adults and children

Dear Dr Lau et al, I was surprised by a lack of consistency of advice within the flow sheet for obesity in adults and children. The guidelines state quite clearly that if patients have not lost 0.5 Kg per week by 3-6 months after lifestyle changes then pharmacotherapy should be considered. However there is no similar time frame for the pharmacotherapy to be assessed or the degree of weight loss that should be considered sufficient for continuation of therapy. This lack of advice in contrast to that provided in regard to lifestyle is puzzling. The 2006 National Institute for Clinical Excellence guidelines on obesity in adults (http://www.library.nhs.uk/diabetes/ViewResource.aspx?resID=213116&tabID=288&catID=5604) states that “pharmacotherapy should be continued beyond 3 months only if the person has lost at least 5% of their initial body weight since starting drug treatment”. Similarly the National Heart, Lung, and Blood Institute (NHLBI) guidelines (http://www.nhlbi.nih.gov/guidelines/obesity/prctgd_c.pdf) state that “If a patient has not lost 4.4 pounds (2 kg) after 4 weeks, it is not likely that this patient will benefit from the drug.” As a family physician this advice is critical to the review of patients with obesity who are being tested for their response to pharmacotherapy. This specific information about duration of the trial period for effectiveness is not contained in the documentation provided by the Canadian manufacturer and needs to be made explicit within the guideline. I strongly urge you to add a section limiting the trial period of pharmacotherapy in line with the limited period for assessing lifestyle modification. Yours sincerely Martin Dawes

Conflict of Interest:

None declared