Associate Professor Jane Smith, author of the article, comments:
Dr French is correct to raise the issue regarding PBS recommendations about use of statins in this patient group.
The risk from ‘family history of cardiovascular disease in first degree relatives under the age of 60 years’ is validated to increase the relative risk of cardiovascular disease by 1.6–1.9.1
The risk from family history of cardiovascular disease has been shown to vary with the age and sex of the first degree relative. If both father and mother have had cardiovascular disease under the age of 50 and 60 years respectively, then the relative risk is increased by 6.9. However, if both father and mother had their cardiovascular disease over the age of 60 and 80 years then the relative risk is only increased by 1.3.2
Logically one could expect family history at a younger age to convey a higher risk, but I am unaware of a calculated value, other than relative risk, and I believe the recommendation to treat as high risk is based on expert opinion.
Such premature onset of cardiovascular disease suggests a genetic predisposition like familial hypercholesterolaemia, but this specific diagnosis is based on a number of criteria.
Risk calculators in the UK (QRISK2) and the New Zealand Heart Foundation adjust for family history. The Australian National Vascular Disease Prevention Alliance risk calculator and the Australian adjusted Framingham risk tables do not. The individual prescriber should accommodate this in their assessment.