High levels of low‐density lipoprotein cholesterol (LDL‐C), colloquially referred to as ‘bad cholesterol,’ can lead to coronary artery disease (CAD), heart attacks and death. While bad cholesterol may result from lifestyle factors, it also can be inherited through heterozygous familial hypercholesterolaemia (FH). Given that cholesterol levels can be mitigated through diet, exercise and certain medications, identifying individuals with FH is imperative as many are unaware of the condition until they have a heart attack. Doing so may help significantly reduce the prevalence and mortality from CAD.
A study published last month by Bellows and colleagues in the Journal of the American Heart Association attempts to assess the potential impact of screening for FH in the US. The authors used logistic regression to predict the probability of finding FH variants from the UK Biobank population and applied the model to the US population screening positive via the Dutch Lipid Clinic Network clinical criteria. The analysis revealed that around 1.1 million individuals could be diagnosed with FH using clinical and genetic testing, while more limited and practical screening could identify around 650,000 FH cases. Without diagnoses, these cases are likely to develop into CAD.
CAD is the most common form of heart disease and, according to GlobalData epidemiologists, will impact roughly 13.1 million individuals over the age of 19 in the US this year (as shown in Figure 1). CAD tends to develop in people who have experienced many years with high levels of bad cholesterol, typically raised by a lack of physical activity, high-fat diet and smoking. Because these factors are easier to identify, many at-risk individuals can be better diagnosed and treated to reduce said cholesterol.
People with FH may not, however, share these characteristics and are thus less likely to be diagnosed with unhealthy cholesterol levels until it is too late, making it challenging to prevent CAD and heart attacks in this population. Screening programs like the one suggested by Bellows and colleagues could help individuals know their status sooner and allow them to initiate treatment to reduce their bad cholesterol levels.
The number of individuals impacted by FH is not insignificant, as the current diagnosed prevalence of FH is around 0.12% of Americans. Translated to the general population, the number of FH cases in adults aged 20 years and older in the US could be more than 312,000 diagnosed prevalent cases, according to GlobalData. If such a large number of individuals were to be diagnosed and treated at a younger age, the resulting decline in bad cholesterol in these cases might lower the prevalence of CAD and subsequently reduce the number of heart attacks in the US. Moving forward, awareness of FH needs to be increased and additional support for FH screening programmes should be considered.