Nearly 1 in 10 With MI at Young Age Have Familial Hypercholesterolemia

By Reuters Staff

May 16, 2019

NEW YORK (Reuters Health) - Familial hypercholesterolemia (FH) is present in 9% of people who experience a myocardial infarction (MI) at age 50 or younger, most of whom continue to have elevated cholesterol at one-year follow-up, according to new research.

"These findings reinforce the need for more aggressive lipid-lowering therapy in young FH and non-FH patients post-MI," Dr. Ron Blankstein of Brigham and Women's Hospital in Boston and colleagues conclude in the Journal of the American College of Cardiology, online May 13.

More than 90% of patients with FH are not diagnosed, Dr. Blankstein and his team note. Current estimates of FH prevalence in the U.S. general population range from one in 212 to one in 250, they add.

To estimate the prevalence of FH in young MI survivors, they looked at data from the YOUNG-MI registry on 1,966 survivors of early heart attack, with a median age of 45. Nineteen percent were female and 54% had ST-segment elevation MI.

Based on Dutch Lipid Clinic (DLC) criteria, 180 (9%) had probable or definite FH, 42.8% of whom were not on a statin before having an MI.

At discharge, 89.4% of the FH group and 89.9% of the non-FH group were on statins; high-intensity statins were prescribed to 63.3% of those with FH and 48.4% of those without FH.

During follow-up, which lasted more than 10 years, there was no difference between the two groups in all-cause or cardiovascular mortality.

Survivors of early MI should undergo assessment for FH before discharge with a validated tool like the DLC, rather than basing diagnosis on LDL-C levels alone, Dr. G. Kees Hovingh of Academic Medical Center in Amsterdam, the Netherlands, and colleagues write in an editorial accompanying the study.

"In addition, a single Lp(a) measurement is needed. Among those who are probable or definite FH, genetic testing should be offered to assess whether autosomal dominant FH is present, as this will open the door to cascade testing and treatment of FH," they add.

"The observation that there were no mortality differences between FH and non-FH patients makes it hard to justify the notion that the FH patients in this cohort should have been given further add-on lipid-lowering therapies, such as ezetimibe and PCSK9 inhibitors, routinely. Any conclusion on this, however, has to be drawn with great care, because it was stated by the authors that this study was probably under-powered to perform a sufficient survival analysis," they conclude.

Amgen, which makes the cholesterol-lowering drug evolocumab (Repatha), helped fund the research, and several study authors are employees and/or stockholders in the company.


J Am Coll Cardiol 2019.