FH and CHD Risk
FH Means High CHD Risk
People with familial hypercholesterolemia (FH) have a high CHD risk because of lifelong exposure to high cholesterol levels.
By age 40, people with FH have arteries that resemble those of typical people in their 80s.5
Untreated FH patients are at 20 times greater risk of premature coronary heart disease (CHD) than the overall population, due to atherosclerosis beginning in childhood and adolescence. Additional risk factors, such as current smoking, place FH patients at even higher CHD risk.1 And the presence of multiple CHD risk factors (smoking, obesity, inactivity, etc.) is associated with dramatic acceleration of atherosclerosis development.1
Risk stratification algorithms, such as the Framingham Risk Score, are not applicable to familial hypercholesterolemia patients. The 10-year CHD risk in FH patients is not adequately predicted by any conventional risk assessment tools.1
The graph below compares cumulative LDL exposure over a lifetime in FH patients and normal individuals.
The CHD risk threshold is reached in childhood for FH homozygotes (HoFH) and in early middle age for FH heterozygotes (HeFH). In the graph, the threshold is depicted as a range because it is lowered in the presence of additional risk factors (male sex, hypertension, diabetes, smoking).5
LDL Exposure vs. Age in FH and Normal Population
Smoking, Diabetes, High Lp(a) Levels Increase CHD Risk in FH
All individuals with FH are at high CHD risk, so the use of risk stratification algorithms, such as the Framingham Risk Score, is not appropriate.1 Patients who present with the following are at very high risk:
- Clinically evident coronary heart disease or other atherosclerotic cardiovascular disease
- Family history of very early coronary heart disease (in men, <45 years of age and in women, <55 years of age)
- Currently smoking
- Two or more coronary heart disease risk factors
- Homozygous FH
- High Lp(a) ≥50 mg/dL using an isoform-insensitive assay1
FH Is Often Undetected
Early diagnosis of FH and aggressive lipid lowering can improve outcomes. But familial hypercholesterolemia is frequently undetected because people with FH often appear healthy, lacking risk factors, such as diabetes, high blood pressure, and obesity.1
Despite the fact that FH can be diagnosed clinically and cost-effectively through cholesterol levels and family history, worldwide, 80% of people with FH are unaware that they have the disorder.1
Once an FH patient has been identified, family screening can help identify others who have inherited the gene. Because FH is autosomal dominant, first-degree relatives of FH patients have a 50% chance of having the disorder. FH may be indicated in adults who have low-density lipoprotein (LDL) levels that are above 190. In children or teenagers, LDL levels over 160 may indicate FH.1,4
- High cholesterol in FH is not due to a patient’s diet and exercise habits.
- FH means high risk. Conventional risk assessment (i.e., Framingham Risk Score) does not apply to FH patients.1
- Virtually all patients with FH will need cholesterol-lowering drug therapy in addition to lifestyle changes.1