Lifestyle counseling from specially trained nurse-practitioners in a primary-care setting was no better at preventing weight gain in a 3-year study than was usual care delivered by the primary-care physician, according to a report in the Feb. 28 issue of the Archives of Internal Medicine.
Researchers in the Groningen Overweight and Lifestyle (GOAL) study compared the effects of two different approaches to preventing weight gain in the primary-care setting: structured lifestyle counseling provided by nurse-practitioners versus usual care.
The study subjects were 457 men and women aged 40-70 years who attended 11 primary-care practices in the Netherlands. They had a body mass index between 25 kg/m2 and 40 kg/m2 and concomitant hypertension or dyslipidemia, said Nancy C.W. ter Bogt of University Medical Center Groningen, the Netherlands, and her associates.
These subjects were randomly assigned to usual care with the primary physician (232 patients) or to an intervention in which nurse-practitioners counseled them in four in-person 30-minute individual sessions and one telephone "feedback" session during the first year, followed by one individual and two feedback sessions during the next 2 years.
The nurse-practitioner sessions incorporated several elements of behavioral counseling such as individual goal-setting, keeping food diaries, using pedometers to track physical activity, and addressing barriers to lifestyle change. The primary aim of the intervention was to prevent weight gain and, in those patients who were motivated to do so, to promote the loss of 5%-10% of body weight.
After 1 year, 80% of the subjects in the nurse-practitioner group had not gained any weight, compared with only 64% in the physician group. However, in this follow-up at 3 years, that difference had disappeared. An equal proportion of both groups – approximately 60% – had maintained or lost weight, Ms. ter Bogt and her colleagues said (Arch. Intern. Med. 2011;171:306-13).
Subjects counseled by nurse-practitioners showed a slight advantage in fasting glucose level at 3 years, and there were no differences between the two groups in serum lipid levels or blood pressure levels.
The researchers hypothesized that two visits with the nurse-practitioner after the first year of the intervention may not have been sufficient to help patients sustain weight loss. However, analysis showed that maintaining weight was not related to the number of visits in either study group.
Analysis of data in subgroups of patients showed that those who had attempted to lose weight four or more times in the years preceding the study had less success in preventing weight gain than did those who had not. "This means that our intervention is not suitable for experienced dieters," Ms. ter Bogt and her associates wrote.