PATHWAYS--FULL SCALE STUDY
Condition: Cardiovascular Diseases; Sedentary Behaviors; Obesity
MeSH terms: Cardiovascular Diseases
Study type: Interventional
Phase: Phase 2

Summary: 
      To implement a culturally appropriate school-based, multicenter, randomized trial that
      promotes healthful eating behaviors and increases physical activity to prevent obesity in
      pre-adolescent upper elementary American Indian students.
    

Detailed description: 
      BACKGROUND:

      The American Indian population, including American Indians and Alaska Natives, totals nearly
      1.5 million from over 500 tribes and nearly 300 reservations and Alaska Native villages.
      Earlier in this century, heart disease was rarely noted in American Indians, but in the past
      decade, cardiovascular disease has become the leading cause of death in American Indians.
      Several factors may be responsible for this increase: a decreasing incidence of infectious
      disease, an increasing incidence of diabetes mellitus, and an increasing incidence of
      obesity. Previous research on non-Indian populations indicates that obesity is an independent
      risk factor for cardiovascular disease and that it is associated with increases in other
      cardiovascular disease risk factors such as high blood pressure, diabetes, and low high
      density lipoprotein cholesterol levels. The high prevalence of obesity among American
      Indians, coupled with its role as a risk factor for hypertension, coronary heart disease, and
      diabetes, suggests that a reduction in the average weight of young American Indians would
      improve their health. Reduction of the prevalence of obesity in American Indians has been
      designated as a goal for improving the health of this minority population and reducing health
      disparities in our nation.

      The successful 4-1/2 year feasibility study was followed by the full-scale randomized trial
      involving 1,700 American Indian elementary schoolchildren. Schools were the unit of
      randomization.

      The initiative was developed as a result of consultations with the NHLBI Ad Hoc Committee on
      Minority Populations, the Conference on Obesity and Cardiovascular Disease in Minority
      Populations, and the Indian Health Service. The need for the study was reinforced by the
      preliminary data from the Strong Heart Study confirming the high prevalence of obesity in
      American Indians. The initiative was approved by the Clinical Applications and Prevention
      Advisory Committee in February 1992 and given concept clearance by the National Heart, Lung,
      and Blood Advisory Council in May 1992.

      DESIGN NARRATIVE:

      The Feasibility Phase of the trial was completed in 1995. The organizational structure has
      been established, validation studies to determine an endpoint and formative assessment of the
      tribe communities was completed. Intervention including classroom curriculum, food service,
      physical activity family component and for the measurement methods including obesity,
      physical activity, diet intake, knowledge, attitudes and behavior, and process evaluation
      were completed.

      The full-scale trial started in September 1996. The primary aim was to test the effectivenes
      of a culturally appropriate school-based intervention that promoted increased physical
      activity and healthful eating behaviors to prevent obesity in American Indian upper
      elementary school children. The primary outcome was percent body fat after three years of
      intervention. The major hypothesis was that intervention would result in an absolute
      difference of 3 percent body fat between the control and intervention schools. All students
      enrolled in the second grade in the participating schools during Spring, 1997 participated in
      the baseline survey. Baseline measurements were performed at the end of second grade so that
      the intervention could begin at the start of third grade. The intervention lasted for three
      years. A single cohort of children progressed through third, fourth, and fifth grades.
      Schools were the unit of randomization. Forty-one schools in four centers were stratified
      within each field center on median percent body fat (PBF) at the end of second grade using
      data from the baseline measurement. Schools within a field center were then ranked on median
      PBF. Once stratified, the coordinating center randomly assigned half the schools within each
      stratum to intervention (21) and half to control (20).

      The study completion date listed in this record was obtained from the "End Date" entered in
      the Protocol Registration and Results System (PRS) record.
    

Intervention name(s): exercise; diet
Intervention type(s): Behavioral; Behavioral
Primary purpose: Prevention