Cerebrovascular Risk May Not Be Higher in Familial Hypercholesterolemia

By Lorraine L. Janeczko

December 19, 2018

NEW YORK (Reuters Health) - People with familial cholesterolemia (FH) may not be at increased risk of cerebrovascular disease (CVD) and ischemic stroke after all, according to a registry study from Norway.

Earlier studies on the potential link have produced mixed findings, Dr. Anders Hovland of the University of Tromsoe and colleagues write in Stroke, online November 21.

"Our results raise new questions on the specific role of LDL cholesterol in cerebrovascular disease and ischemic stroke," they note.

The researchers linked people with FH to the nationwide database of CVD hospitalizations between 2001 and 2009. They estimated rates of hospitalization for CVD among 3,144 people with FH, and for ischemic stroke among 3,166 people with FH.

Nineteen women and 27 men with FH had CVD, for a standardized incidence ratio of 1.0; and nine women and 17 men suffered an ischemic stroke, also yielding a SIR of 1.0.

Women with prior coronary heart disease were at significantly increased risk of CVD (hazard ratio, 3.29), but men were not.

The authors acknowledge limitations of their study, including the lack of information about actual lipid levels, medications and lifestyle factors, as well as the issue of selection bias inherent in register studies. They noted, though, that all physicians in Norway may order genetic testing of FH for free, reducing the risk of cost-based bias.

Dr. Sajjad Mueed, an associate professor of clinical neurology at Southern Illinois University School of Medicine in Springfield, told Reuters Health by email, "This is just an observational study without any knowledge of actual levels of cholesterol/LDL, concomitant treatments, and other simultaneous risk factors."

"However," added Dr. Mueed, who was not involved in the study, "it is important to do such studies to have an idea about the natural history of a disease or disorder."

"This study involves a specific population group, and findings cannot be extrapolated to other population groups," he said. "The authors used hospitalization data only, so people with minor and transient symptoms who were not admitted to the hospital would potentially be missed."

"These study findings should not be used to change treatment decisions," Dr. Mureed concluded.

Dr. Hovland did not respond to requests for comment.

SOURCE: https://bit.ly/2PINzq5

Stroke 2018.