Improving the Management of Obesity in Primary Care Practice (The Power-UP Trial)

Obesity, defined by a body mass index (BMI) ≥ 30 kg/m2, affects more than 31% of American adults. Additionally, nearly one-quarter of U.S. adults meet criteria for the metabolic syndrome, a clustering of clinical signs (i.e., elevated waist circumference, blood pressure, glucose or triglycerides, decreased HDL cholesterol) that is associated with increased risk of cardiovascular death. Behavior modification programs and pharmacologic interventions for obesity typically result in an 8% to 10% loss of initial body weight. Losses of this magnitude are associated with clinically significant improvements in metabolic parameters among obese persons. The availability of traditional behavioral weight control programs, however, is limited as many of these programs are based in academic medical centers. Furthermore, pharmacotherapy is seldom covered by third-party payers. Thus, there are concerns about the accessibility of these interventions to the many obese individuals who could benefit from weight loss.

The purpose of the study is to improve the management of obesity in primary care practice, where obesity is commonly encountered but infrequently addressed. Three hundred and ninety persons at 6 primary care practices within the University of Pennsylvania Health System will be randomized to one of three 2-year interventions: Usual Care, Brief Lifestyle Counseling, or Enhanced Brief Lifestyle Counseling. After training in obesity management and intervention strategies, each site will enroll approximately 65 individuals with a BMI of 30-50 kg/m2 plus two or more components of the metabolic syndrome. Participants in the Usual Care condition (N=130) will receive educational materials plus quarterly visits with a primary care provider (PCP). Those in the Brief Lifestyle Counseling condition (N=130) will receive the same PCP visits, plus 26 brief counseling sessions with an auxiliary health care provider (e.g., a medical assistant), on-site or by phone. Participants in the Enhanced Brief Lifestyle Counseling condition (N=130) will additionally receive the same treatment as those in the Brief Lifestyle Counseling group, plus the choice of adjunctive meal replacements or pharmacotherapy.

Two-year changes in weight will be compared across groups. Participants who receive the Brief Lifestyle Counseling and the Enhanced Brief Lifestyle Counseling interventions are predicted to achieve greater weight loss than those who receive Usual Care. A secondary hypothesis is that participants in Enhanced Brief Lifestyle Counseling condition will lose significantly more weight at month 24 than participants in the Brief Lifestyle Counseling group. Secondary analysis will also compare changes in the metabolic syndrome (and its individual components), mood, quality of life, dietary intake, eating behavior, appetite, physical activity and sexual function, as well as cost-effectiveness, among the three conditions. Intervention protocols and study results will be disseminated to other health care providers and payers.

Inclusion criteria

• Age ≥ 21 years

• BMI 30-50 kg/m2 and weight ≤ 400 lbs.
• At least 2 of 5 criteria for metabolic syndrome

• Elevated waist circumference (> 102 cm for men, > 88 cm for women)
• Elevated blood pressure (≥ 130/85 mmHg)
• Impaired fasting glucose (≥ 100 mg/dl)
• Elevated triglycerides (≥ 150 mg/dl)
• Low HDL cholesterol (< 40 for men, < 50 mg/dl for women)
• Willing to change diet, physical activity and weight
• Willing to accept randomization to each group
• Able to give informed consent
• Patient of participating PCP

Persons with the following conditions are eligible with PCP approval:

• Diabetes mellitus
• Prior CVD event > 6 months before randomization
• Stable CVD or peripheral vascular disease

Exclusion criteria

• Serious medical condition likely to hinder accurate measurement of weight, or for which weight loss is contraindicated, or which would cause weight loss (e.g., end-stage renal disease on dialysis, cancer diagnosis or treatment within 2 yrs)
• Prior or planned bariatric surgery
• Chronic use (at least past 6 months) of medications likely to cause weight gain or prevent weight loss (e.g. corticosteroids, lithium, olanzapine, risperidone, clozapine)
• Unintentional weight loss within 6 months of enrollment (≥ 5% of body weight)
• Intentional weight loss within 6 months of enrollment (≥ 5% of body weight)
• Pregnant or nursing within past 6 months
• Plans to relocate from the area within 2 years
• Another member of household is a study participant or staff in the trial
• Consumes > 14 alcoholic drinks per week
• Current use of illicit substances
• Psychiatric hospitalization in last year
• Psychiatric condition likely to impair adherence to treatment (e.g., schizophrenia)
• Blood pressure ≥ 160/100 mmHg; patient may be re-screened in 1 month
• Principal Investigator or PCP discretion