This US-based study randomised 390 obese adults in 6 primary care practices to one of three types of intervention: Usual care, consisting of quarterly primary care provider (PCP) visits that included education about weight management; Brief lifestyle counselling, consisting of quarterly PCP visits combined with brief monthly sessions (10- to 15-min encounters) with lifestyle coaches who instructed participants about behavioural weight control; or Enhanced brief lifestyle counselling, which provided the same care as described for the previous intervention but included meal replacements or weight-loss medication (sibutramine or orlistat), chosen by the participants in consultation with the PCPs, to potentially increase weight loss. All interventions were delivered by the PCPs over a 2-year period in collaboration with auxiliary health professionals (lifestyle coaches) in their practices. Over 85% of participants completed the trial, at which time, the mean weight loss with usual care, brief lifestyle counselling, and enhanced brief lifestyle counselling was 1.7, 2.9, and 4.6 kg, respectively. Initial weight decreased at least 5% in 21.5%, 26.0%, and 34.9% of the participants in the three groups, respectively. For both of these measures of success, enhanced lifestyle counselling was superior to usual care; there were no other significant between-group differences. The benefits of enhanced lifestyle counselling remained even after excluding sibutramine recipients from the analyses.
