Actionable evidence: How to tackle obesity in primary care?

Posted: Tuesday, October 25, 2011 | Posted by Debajyoti Datta | Labels: ,

Scenario: A 45 year old male with a BMI of 32 presents to his primary care physician. What intervention should be suggested to him to reduce his BMI? Should only behavioral modification be adequate or should orlistat be added to it?

Evidence: A recent study titled “Effectiveness of Primary Care–Relevant Treatments forObesity in Adults: A Systematic Evidence Review for the U.S. PreventiveServices Task Force" published in the Annals of Internal Medicine looks into the evidence.

The study tried to answer 4 key questions –
  1. Is there direct evidence that primary care screening programs for adult obesity or overweight improve health outcomes or result in short-term (12 to 18 mo) or sustained (>18 mo) weight loss or improved physiologic measures? a) How well is weight loss maintained after an intervention is completed?
  2. Do primary care–relevant interventions (behaviorally based interventions and/or pharmacotherapy) in obese or overweight adults lead to improved health outcomes? a) What are common elements of efficacious interventions? b) Are there differences in efficacy between patient subgroups (i.e., age 65 y or older, sex, race/ethnicity, degree of obesity, baseline cardiovascular risk)?
  3. Do primary care–relevant interventions in obese or overweight adults lead to short-term or sustained weight loss, with or without improved physiologic measures? a) How well is weight loss maintained after an intervention is completed? b) What are common elements of efficacious interventions? c) Are there differences in efficacy between patient subgroups (i.e., age 65 y or older, sex, race/ethnicity, degree of obesity, baseline cardiovascular risk)?
  4. Do primary care–relevant interventions in obese or overweight adults lead to short-term or sustained weight loss, with or without improved physiologic measures? a) How well is weight loss maintained after an intervention is completed? b) What are common elements of efficacious interventions? c) Are there differences in efficacy between patient subgroups (i.e., age 65 y or older, sex, race/ethnicity, degree of obesity, baseline cardiovascular risk)?

Outcome: The first key question remains unanswered as the authors were unable to identify any study comparing screening vs non-screening of obese individuals.

The second, third and fourth key questions were answered. The summary –

Behavioral interventions

Parameter
Outcome
Weight Loss
Weighted mean difference in mean weight change between behavioral intervention and control group is -3.01 kg 95% CI (-4.02 to -2.01) at 12 to 18 months. Behavioral interventions lasting longer continued to show weight loss. Weight los was maintained up to a year following active intervention phase.
Mortality
No difference in death rate but limited by small number of trials.
Cardiovascular disease
No difference in CVD events or CVD related deaths in 3 large good quality trials
Hospitalization
No difference, limited by low hospitalization rate.
Health related quality of life/depression
No difference in depression, small favorable change of health related quality of life with weight loss
Incidence of diabetes mellitus
Weight loss of 4 to 7 kg reduced diabetes incidence by 50% or more over 2 to 3 years.
Glucose tolerance
Mean decrease in glucose level = 0.30 mmol/L (5.4 mg/dL)
Lipids
Weighted mean difference in LDL cholesterol level between treatment and control group = -4.94 mg/dL 95%CI (-7.32 to -2.56)
Blood pressure
Weighted mean difference in mean change in blood pressure between treatment and control group = -2.48 mmHg 95%CI (-3.25 to -1.71)
Waist circumference
-2.7 cm 95%CI( -4.1 to 1.4)
Adverse effects
None

Orlistat (Note- Almost all the trials of orlistat had simultaneous behavioral interventions)

Parameter
Outcome
Weight Loss
Weighted mean difference between behavioral intervention and control group is -2.98 kg 95% CI (-3.92 to -2.05).
Mortality
There were 4 studies which reported this outcome. Each study reported 1 death in in the orlistat group, but no clear relationship with treatment.
Cardiovascular disease
Not reported.
Hospitalization
Not reported.
Health related quality of life/depression
No difference in depression, Orlistat had greater satisfaction with treatment, less overweight distress and improvement in the vitality subscale of SF – 36.
Incidence of diabetes mellitus
Decreased incidence by 9-10% but concerns regarding generalizability and reliability.
Glucose tolerance
Mean decrease in glucose level = 0.31 mmol/L (5.5 mg/dL). Glucose reductions are greater in orlistat than placebo possibly because they were conducted in diabetic patients.
Lipids
Weighted mean difference in LDL cholesterol level between treatment and control group = -11.37 mg/dL 95%CI (-15.75 to -7.00)
Blood pressure
Weighted mean difference in mean change in blood pressure between treatment and control group = -2.04 mmHg 95%CI (-2.97 to -1.11)
Waist circumference
-2.3 cm 95%CI( -3.6 to -0.9)
Adverse effects
Gastrointestinal symptoms of mild to moderate intensity which resolves spontaneously, liver injury, vitamin E and K deficiency, increased incidence of hypoglycemia.

The authors also examined metformin which had modest effects on weight loss -2.85 kg 95%CI (-3.52 to -2.18).

Comment
The behavioral interventions included counseling regarding the importance of diet and exercise. There the interventions were not described fuly in the study. There was variability in the methods employed for behavioral modifications in the between the studies. On the other hand, orlistat studies had high attrition rate and were mostly funded by pharmaceutical companies.

Bottom line
In the primary care setting, behavioral intervention is effective and safe and should be considered as a first line therapy for weight loss. Orlistat may be added later. There are significant adverse effects associated with orlistat. Metformin may be tried in diabetics.

ResearchBlogging.org Leblanc ES, O'Connor E, Whitlock EP, Patnode CD, & Kapka T (2011). Effectiveness of primary care-relevant treatments for obesity in adults: a systematic evidence review for the u.s. Preventive services task force. Annals of internal medicine, 155 (7), 434-47 PMID: 21969342

7 comments:

  1. Pranab said...
  2. Good summing up! I think the problem with the society today is that when they come to the the doctors, they expect a pill for all their ills, including obesity, and when THAT does not happen, it becomes a healthcare delivery issue. While I agree BCC remains the main form to combat the growing problem of obesity, I still have major concerns over the compliance issues. And these matters have a lot of loco-regional variations based on socio-cultural implications of obesity. In certain Indian cultures, for example, obesity is a marker of affluence!

    Anyways. This is an important problem and thanks for the brilliant review!

  3. Debajyoti Datta said...
  4. Thanks for dropping by Pranab da!

    You are obviously right about the compliance issue. Also one of the drawbacks of this review is that it does not specify which behavioral modifications were adopted. I think some of the interventions are more difficult to adhere to than others. It would have been nice to have some information on that.

  5. sriramnivas said...
  6. Obesity is a slow killer and if not taken care of, may lead to dire consequences....So, better eat healthy and think better.
    Wish u a Happy & prosperous Diwali!!!

    From: sriramnivas.wordpress.com

  7. Debajyoti Datta said...
  8. Happy diwali to you too sriramnivas!

  9. Pranab said...
  10. I think you should check out http://csjc.informer.org.in I think you could REALLY make some contributions there. Why not check it out and see how things are dealt with there?

  11. Debajyoti Datta said...
  12. Thanks for the link Pranab da. I will check it out.

  13. Gynecologist mountain view, ca said...
  14. Thank you so much for the wonderful information .This is really important for me .I am searching this kind of information from a long time and finally got it.

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