The evidence cards
Study results help frame a question.
A study result tells you what happened in a group. Ask how that group compares with your situation, and what the result can and cannot tell you.
Weight changed in the study
In the SURMOUNT-1 study, adults who did not have diabetes lost an average of roughly 15% to 21% of their starting weight during 72 weeks on tirzepatide. People given a shot without tirzepatide, called a dummy shot, lost about 3%. The dummy shot lets researchers compare results with and without the medicine.
The study was supported by the drug's maker and included regular visits and help with eating and activity.
- How close is my health history to the study group's?
- What support would be part of my care?
- How would we assess progress for me?
- What would count as a reason to reconsider the plan?
Stopping was studied, too
In the SURMOUNT-4 study, people first received tirzepatide for 36 weeks. They then either continued it or switched to a shot without tirzepatide.
Over the next 52 weeks, the group that switched gained an average of 14% of their body weight measured when they switched. The group that stayed on tirzepatide lost another 5.5%, also measured from their weight at that point. The 14% is a share of body weight, not a share of the weight already lost.
For an example of the arithmetic, 14% of a body weight of 200 pounds is 28 pounds. This is an illustration, not another study result.
Those results open a discussion about later care. They do not set a personal stop date or decide how long anyone must continue.
- How would we plan for stopping if that becomes the choice?
- What other support would remain available?
- What changes in health or cost would prompt a review?
Ask who funded the evidence
A Cochrane review, which brings together results from several studies, found that tirzepatide likely reduces weight more than a treatment without the medicine. The drug maker paid for all the studies in that review.
- Ask which named study supports an advertised result.
- Write down both results: the weight change with tirzepatide and the weight change without it. Compare them side by side.
- Ask what remains uncertain, rather than treating an average as a promise.
Sources for this chapter
Use these sources to check the answers above. Bring any questions to the person treating you.