Gene link to statin myalgia
People who complain of myalgia caused by statins may be suffering from a genetic problem, according to a recent paper published in the European Heart Journal.
Researchers from Dundee University, UK, looked at a genetic variant in the LILRB5 gene – Asp247 – as it had been reported to be linked with lower levels of creatine phosphokinase and lactate dehydrogenase. These biomarkers are important as they are released from injured muscle tissue, and altering their levels help ease muscle-related pain.
The study examined Asp247 using medical records from a large study database including over 18,000 patients and reported statin intolerance. The results showed that the Asp247 variant was significantly associated with two 'statin intolerance phenotypes', one with patients tending to have raised creatine phosphokinase, and the other as patients being intolerant to a low statin. Participants who were homozygous for Asp247 had increased odds of developing both definitions of intolerance. The team then replicated these findings on a group of participants in a second large study (the CPRD-STAGE study).
Study author, Professor Colin Palmer said: "We found that there are people in the general population who carry a genetic factor that predisposes them to muscle aches. If these people are put on statins, they might discontinue their medication in the erroneous belief that it is the statin that is making their muscles ache.
"At the same time, we observed that there is a genetic sub-group of patients who are susceptible to statin-specific muscle ache, although at this stage we don't understand the mechanism responsible for this effect."
He added: "This means that it would be possible to test prospective statin users for key genetic variants, including LILRB5, to prevent people being put on statins if they are likely to have an adverse reaction."
The study identifies a genetic group of patients who are likely to be intolerant to statin therapy. It also suggests a distinction between true statin-induced myalgia and non-specific myalgia.
Siddiqui, M. K. et al. A common missense variant of LILRB5 is associated with statin intolerance and myalgia. European Heart Journal 29 August 2017; doi:10.1093/eurheartj/ehx324