Apolipoprotein(a) Isoform Size and Lipoprotein(a) Concentration and Acute Myocardial Infarction Risk in China: the INTERHEART China Study
In brief
Small apolipoprotein(a) isoforms linked to 83% higher heart attack odds
Among Chinese participants with two measured apolipoprotein(a) isoforms, carrying a smaller isoform was associated with 83% higher odds of a first heart attack; high lipoprotein(a) levels were also linked to greater risk. For participants with a single isoform, size was no longer associated with risk after accounting for lipoprotein(a), so whether genotyping improves risk prediction still needs testing.
- Journal
- The American journal of cardiology (Q2)
- Published
- 6 October 2026
- Study design
- Case-control study
- Evidence level
- Level 3, Low (CEBM 3b)
- Authors
- Xiaonan Ma, Jinsong Jiang, Ying Wei, Chunyan Lan, Binong Su, Xin Liu, et al.
- PMID
- 42838438
- DOI
- 10.1016/j.amjcard.2026.09.019
Why clinicians should know about it
- Picked for Biochemistry (medical) (top studies of the week, 11 October 2026): Lp(a) isoform size linked to AMI risk
Abstract
There are limited effective methods or biomarkers for assessing the risk of acute myocardial infarction (AMI). This study evaluated the distribution characteristics of plasma lipoprotein(a) [Lp(a)] concentrations and apolipoprotein(a) [apo(a)] isoform sizes. Then, we investigated their independent and interactive associations with the risk of AMI. Based on the INTERHEART China case-control study, 1,908 participants (963 patients with first-time AMI and 945 age and sex matched controls) were enrolled. Risk factors, including lifestyle, metabolic markers, and psychosocial factors were collected using standardized questionnaires. Lp(a) concentrations were measured using an isoform-insensitive immunoassay, and apo(a) isoform sizes were quantified in all participants via Western blotting. Multivariate logistic regression models were used to analyze risk associations; restricted cubic splines were applied to assess dose-response relationships, and interactions were tested. High Lp(a) concentrations were significantly associated with an increased risk of AMI. Overall, a consistent negative correlation was observed between apo(a) isoform size and Lp(a) concentration. Further, In the single isoform subgroup, smaller apo(a) size was associated with a higher AMI risk in the unadjusted model, but this association became non-significant after adjusting for Lp(a) levels. However, in the dual isoform subgroup, carrying smaller isoforms (< 23) was associated with a significantly higher AMI risk (OR, 1.83;95% CI, 1.12-3.04), while larger isoform sizes (>29) showed a trend towards higher risk of MI. In conclusion, our findings suggest that current cardiovascular risk stratification might be optimized by integrating both Lp(a) mass and isoform genotyping, offering a new perspective on the precise risk stratification of AMI patients.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.