Rural Lifestyle Intervention Treatment Effectiveness Trial

Higher rates of obesity, sedentary lifestyle, and coronary heart disease are observed in
rural than in non-rural areas of the U.S., yet the treatment of obesity in the rural
population has received little attention. Efficacy trials, conducted in academic health
centers, show that lifestyle interventions can produce sufficient weight reductions to
improve health, but very few trials have been carried out in medically underserved community
settings. Moreover, the high intensity of treatments used in efficacy studies represents a
barrier to dissemination into rural settings. The existing infrastructure of the United
States Department of Agriculture Cooperative Extension Service, with over 2900 offices
nationwide, may serve as a valuable resource for bringing lifestyle interventions to rural
areas. Preliminary data from our rural obesity research program show promising findings for
lifestyle interventions delivered through Extension offices. The next logical step in this
line of research is to determine the minimum intensity of treatment required to produce
clinically meaningful, long-term weight reductions. We propose to conduct a single-blind,
multi-site, randomized controlled trial in obese adults (N=542) to evaluate the effects of
LOW, MODERATE, and HIGH doses of lifestyle treatment on two-year changes in body weight,
compared to an education CONTROL condition. The LOW intensity condition reflects the dose of
group treatment commonly used in community settings, whereas the HIGH dose corresponds to the
intensity level employed in efficacy trials. The MODERATE intensity intervention represents a
treatment dose that our preliminary data suggest may provide benefits comparable to the HIGH
intensity intervention. Our principal hypothesis is that both the MODERATE and HIGH
interventions will produce greater weight reductions at two years than either the LOW or
CONTROL conditions. We will also evaluate the proportion of participants in each condition,
who achieve clinically significant weight losses, and we will examine changes in metabolic
risk factors, dietary intake, physical activity, and quality of life. We will calculate the
cost-effectiveness of the interventions, and we will investigate potential mediators of
long-term change.

Inclusion Criteria:

- Age: 21 to 75 years

- Body Mass Index: 30 to 45 kg/m**2

Exclusion Criteria:

- Underlying disease likely to limit lifespan and/or increase risk of
interventions:cancer requiring treatment in past five years (exception: non-melanoma
skin cancer); serious infectious diseases (e.g., self-reported HIV, self-reported
tuberculosis or treatment); myocardial infarction or cerebrovascular accident within
the last six months; unstable angina within the past six months; congestive heart
failure; chronic hepatitis; cirrhosis; chronic malabsorption syndrome; chronic
pancreatitis; irritable bowel syndrome; previous bariatric surgery; history of organ
transplantation; history of musculoskeletal conditions that limit walking; chronic
lung diseases that limit physical activity; and any other condition likely to limit
five-year life expectancy.

- Metabolic exclusions: fasting blood glucose > 125 mg/dl at screening if not known to
be diabetic (diabetic patients under active treatment will be enrolled if approved by
primary provider); fasting serum triglycerides > 400 mg/dl at screening; resting blood
pressure > 140/90 mm Hg.

- Medication exclusions: antipsychotic agents; monoamine oxidase inhibitors; systemic
corticosteroids; antibiotics for HIV or Tuberculosis; chemotherapeutic drugs; or use
of prescription weight-loss drugs within six months.

- Conditions or behaviors likely to affect the conduct of the trial: unwilling or unable
to give informed consent; unable to read English at the 5th grade level; unwilling to
accept random assignment; unwilling to travel to Extension office for intervention
sessions; participation in another randomized research project; weight loss > 10
pounds in past six months; likely to move out of the county in next two years; major
psychiatric disorder; excessive alcohol intake; BMI > 45; prior participation in the
TOURS trial; and other conditions which in the opinion of staff would adversely affect
participation in the trial