Evidence-Based Medicine for Student Health Services
Robert J. Flaherty, MD
Swingle Student Health Service
Montana State University
Bozeman, MT 59717
Weight Management
 
Etiology Monitoring
Epidemiology Prognosis
Diagnosis Prevention
Treatment Patient Education
 
General Information
   
EBM for Student Health  
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Specific Conditions/Diseases
  
    		   
Etiology 
No evidence is cited. 
  
Epidemiology 
No evidence is cited. 
  
Diagnosis 
Clinical Diagnosis
Body Mass Index (BMI) is a reliable index to evaluate the body fat. (Click here for BMI calculator or BMI chart) Laboratory/X-ray Diagnosis
No evidence is cited. 
   
Treatment  
Behavioral/Cognitive Therapy 
Of the cognitive strategies studied, cue avoidance was the only technique with some evidence of effectiveness. Extending the length of behavioral therapy also appeared to be more effective when compared to an intervention of shorter duration. There was no evidence to suggest that monetary contracting as an individual versus groups may be of value in the weight loss process.  It is possible that some elements of a weight loss programme by correspondence may be useful, for example, the provision of lessons and homework.  The practice of daily weight charting may be helpful for both weight loss and maintenance of weight loss.   Diet Therapy 
Combining very low calorie diets (VLCDs) with behavioral therapy appears to be more effective than treating obese adults with either VLCD or behavior therapy alone. There is no difference in the effectiveness of fat restriction alone compared to fat and calorie restriction in the longer term (i.e. at one year follow-up) in non-diabetics. The restriction of both fat and calories may be helpful in the shorter term. The provision of meal plans and grocery lists may be of benefit as a weight loss intervention. There is no demonstration of the superiority of either inpatient or outpatient management of obesity. The combination of diet and exercise in conjunction with behavioral treatment, however, does appear to be more beneficial for weight loss than diet alone. When diet and exercise were combined in the absence of behavioural treatment, the combination was no more effective than diet and exercise as single interventions. Increased dietary fibre does not appear to show a greater mean weight loss when compared to a low fibre/low carbohydrate diet.  However, fibre supplements appear to be more effective than placebo at increasing weight loss for subjects receiving a 1200 kcal/day diet.  Exercise 
Exercise appeared to be of benefit when compared to a group receiving no exercise. The evidence for the effectiveness of exercise versus dietary education remains unclear, although both these treatment conditions had superior weight losses at the end of the weight loss intervention compared to a no-treatment control. Pharmacotherapy 
Pharmacological interventions did not appear to be effective in producing sustained long term weight loss.  Phenylpropanolamine is safe and effective for weight loss (0.14-0.27 kg/wk when compared to placebo), appears less effective than prescription anorectics in studies exceeding 4 wk, and weight loss was not enhanced by combination with benzocaine.   There is no scientific evidence that human chorionic gonadotropin (hCG), as used in the Simeons therapy, causes weight-loss, a redistribution of fat, staves off hunger or induces a feeling of well-being.   Surgery 
There is good evidence to indicate the effectiveness of gastric bypass in the treatment of morbidly obese patients (those with BMI>40). However, surgery is associated with complications.  Other Therapies
No clear picture emerges to show that acupuncture or acupressure is effective in reducing appetite or body weight.
  • Caveats
    • Age group studied: Unknown
    • Type/size: Systematic review of 4 RCTs (270 participants)
    • Population characteristics: Two trials involved obese volunteers, one trial involved volunteers and one trial involved obese women
    • Outcome measures: Body weight reduction; appetite
  • Citations
   
Monitoring/Maintenance
The majority of the studies demonstrate weight regain either during treatment or post-intervention. The addition of self-help peer groups in addition to therapist led booster sessions was shown to be effective in maintaining weight loss. However, after the maintenance program ended, weight regain occurred. One of the most effective maintenance programs consisted of behavioral therapy and continued therapist contact by mail and telephone. The involvement of the family or spouse in both weight loss and maintenance phases appeared to be of some benefit, although the differences in treatment effect were not statistically significant.   
Prognosis  
In women, higher levels of adiposity within the "normal" range, as assessed by the body mass index, were associated with an increased risk for fatal and nonfatal coronary heart disease (CHD). Even modest weight gains after 18 years of age were also associated with a higher risk for CHD.  High levels of obesity indicators, such as body mass index (BMI) and skinfold thickness, are only slightly associated with an excess mortality and that overweight and obesity are health hazards only if they are accompanied by an elevation of other risk factors, mainly of blood pressure. The minimum risk for men is around 28 units of BMI, and it decreased to smaller levels of body mass index after the exclusion of smokers, people carrying severe diseases at entry and/or those who died during the first 5 years of the study. The analysis of skinfold thickness showed similar but less clear-cut results. Among women, due to the limited number of fatal events, the analysis was unable to show any clear relationship of body mass index or skinfold thickness to all-causes mortality.   
Prevention/Intervention 
General practice-based health programs, consisting of brief or intensive advice, have a modest and variable effect on health outcomes. These interventions show promise in effecting small changes in behavior.   
Patient Education
The following patient education materials are consistent with the available evidence.
Rev. 8/1/01
  
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