Is there a ceiling effect for GLP-1-mediated weight loss? — looking for input

InsuranceTom said:

Read four things before the headline number.

I read this differently from InsuranceTom, on substance rather than tone. I would add the less popular caveat: these trial populations under-represented several groups, older adults and the highest BMI categories among them. The results probably generalise, and "probably" should be stated as an assumption rather than dropped.

VanRx_Mike said:

My own curve sits about four points below the published mean and I spent two months assuming that meant something was wrong with me or with my…

VanRx_Mike said:

...regarding the trial evidence...

I think this is an underappreciated point. To expand on it with some data:

A recent meta-analysis of 12 RCTs (n=8,400) found that the trial evidence was associated with a significant effect size across diverse patient populations[1].

The NNT was 8, which is comparable to antihypertensives for stroke reduction. That's a strong clinical argument for this approach.

NurseKim_ATL said:

I would add the less popular caveat: these trial populations under-represented several groups, older adults and the highest BMI categories among them.

Bayesian meta-analysis perspective on the trial evidence: traditional frequentist meta-analyses report point estimates and confidence intervals. Bayesian approaches provide probability distributions that are more intuitive for clinical decision-making.

For example: "There is a 98.5% probability that semaglutide 2.4mg produces >10% weight loss vs placebo" is more actionable than "RR 3.4, 95% CI 2.8-4.1, p<0.001."

The the trial evidence evidence is strong under both frameworks, but Bayesian analysis better communicates the degree of certainty for individual patient counseling.

One thing that is still open after PharmHunterJen’s answer:

Did your prescriber agree with that reading, and if not what was their objection?

Reporting back.

Follow-up: I read the paper rather than the summary and the qualifier I was missing was in the second paragraph of the results.