In one sentence
An LDL-like particle with an extra protein, apolipoprotein(a), stitched to it, whose level in your blood is set almost entirely by your genes and stays roughly the same for life, which is why one measurement is enough.
Why it matters
In the Copenhagen City Heart Study (8,637 people followed for 16 years) and the Copenhagen General Population Study (29,388 people), the hazard of myocardial infarction rose with lipoprotein(a): 1.9 times for levels in the 90th to 95th percentile and 2.6 times above the 95th, compared with the lowest fifth, and because the gene variants that set the level carried the same association, the finding was consistent with cause rather than coincidence (Kamstrup 2009). The 2022 European Atherosclerosis Society consensus reviewed studies of hundreds of thousands of people and described a causal, continuous association between lipoprotein(a) concentration and cardiovascular outcomes, present even when LDL cholesterol was very low, and an association with calcification and narrowing of the aortic valve; it recommended measuring lipoprotein(a) at least once in every adult (Kronenberg 2022). For most people the result is low and the question is closed; for about one in five it is high enough that the consensus treats it as a reason to manage every other factor more carefully, since medicines that lower it specifically were still in trials at the time of writing.
What moves it
Very little. The size of the apolipoprotein(a) gene explains most of the difference between people, and diet and exercise barely touch it. Kidney disease, the menopause and thyroid state shift it modestly; a few medicines lower it. It rises during an acute illness like other acute-phase proteins, so the two-week rule before a draw applies.
How to measure it well
Once, at any age, with no fasting needed (Nordestgaard 2016). Ask for the result in nmol/L. Older assays report mg/dL, a mass, and because the apolipoprotein(a) protein comes in different sizes the mass does not convert to a particle count by any fixed factor; VT keeps nmol/L and mg/dL as two separate series and says so on the chart rather than converting. The test is not funded in New Zealand and is a self-pay addition to any draw.
How Vitality Tracker uses it
Stored as reported, with the laboratory's range and flag, never overridden. Typical New Zealand laboratory reference < 75 nmol/L; VT's working optimal (v0.1) is the same figure, so VT adds no second line beyond the laboratory's own, and the consensus bands it describes (below about 75 nmol/L as low, above about 125 nmol/L as high, the span between as a grey zone) are shown as the consensus's reference points, with the European laboratory flagging thresholds of 50 mg/dL, the 80th percentile, and 150 mg/dL, the 99th (Nordestgaard 2016). No re-test reminder is set, unless a treatment that lowers lipoprotein(a) is started. The result is listed in the pre-visit report as a once-only test, and a result above the laboratory's range prompts the consultation suggestion.
How far to trust the number
Laboratory: assays have improved but still differ, because the protein's variable size can bias the older ones; the consensus prefers assays that are insensitive to the size of apolipoprotein(a) and reports in nmol/L. Compare results only within one assay.
Sources
- Kronenberg F, et al. Lipoprotein(a) in atherosclerotic cardiovascular disease and aortic stenosis: a European Atherosclerosis Society consensus statement. Eur Heart J 2022;43:3925–46. doi:10.1093/eurheartj/ehac361
- Kamstrup PR, Tybjaerg-Hansen A, Steffensen R, Nordestgaard BG. Genetically elevated lipoprotein(a) and increased risk of myocardial infarction. JAMA 2009;301:2331–9. doi:10.1001/jama.2009.801
- Nordestgaard BG, et al. Eur Heart J 2016. doi:10.1093/eurheartj/ehw152
- Kronenberg F, et al. Frequent questions and responses on the 2022 lipoprotein(a) consensus statement of the European Atherosclerosis Society. Atherosclerosis 2023;374:107–20. doi:10.1016/j.atherosclerosis.2023.04.012
- Vitality Tracker, Recommended baseline lab panel v0.1; Lab results data model (non-convertible units).