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Why does my ApoB disagree with my LDL-C?

Asked 21 Jul 2026Modified 8 days agoViewed 3.5k times
11

I have the full paper rather than the abstract, and the supplementary appendix.

I have the document in front of me and I can read the numbers. What I cannot do is interpret them.

I am reasonably comfortable with statistics and completely uncomfortable with chromatography, or vice versa.

Which parts of this are informative and which are decoration?

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askedbea_forsberg14k2821 Jul 2026
The timing signature is the useful part. Everything else is confounded. – g_paskevicius 5 months ago
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1 Answer

Accepted answer first, then by votes
53

Accepted answer

Start with the population. The inclusion criteria of the trial determine what its result can be extrapolated to, and the extrapolation people want is usually to a population the trial excluded.

Absolute risk reduction, worked: if the control-arm event rate is 8.0 per cent over the follow-up period and the hazard ratio is 0.80, the treated rate is approximately 6.4 per cent, the absolute risk reduction is 1.6 percentage points, and the number needed to treat is 1 ÷ 0.016 ≈ 63 over that period. A 20 per cent relative reduction and a number needed to treat of 63 are the same finding stated two ways, and only one of them sounds impressive.

Relative to absolute, worked

QuantityValueDerivation
Control-arm event rate8.0 %From the trial table, not the abstract
Hazard ratio0.80Reported
Treated event rate6.4 %8.0 × 0.80
Absolute risk reduction1.6 pp8.0 − 6.4
Number needed to treat631 ÷ 0.016
Relative risk reduction20 %1 − 0.80

The last two rows describe the same finding. Only one of them is used in headlines.

The rodent thyroid C-cell findings that generated the labelled warning appear to be species-specific: rodent C-cells express GLP-1 receptors at high density, human C-cells at very low density, and human calcitonin data across large trial populations has not reproduced the signal. A family history of medullary thyroid carcinoma or MEN2 is nonetheless a genuine contraindication rather than a theoretical one.

STEP 1 reported a mean weight change of approximately −14.9 per cent with semaglutide 2.4 mg versus −2.4 per cent with placebo at 68 weeks[1]; the difference between the figures quoted from this trial in different places is an estimand difference.

Read the confidence interval, read the estimand, and compute the absolute effect yourself. It takes two minutes and it changes how the result feels.

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answered · acceptedfibre_or_fragment12k1822 Jul 2026
3Worth flagging that this changed in 2025, so older answers on the site are out of date. – tandem_gradient 2 months ago
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Ask PeptideStack is a static archive. Posting is closed, but the norms are worth stating: answer the question that was asked, show your working, cite the trial or the certificate, and say plainly where the evidence runs out.

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