Genetic polymorphisms in ABCB1 are correlated with the increased risk of atorvastatin-induced muscle side effects: a cross-sectional study.

Genetic factors are recognized as risk factors for statin-associated muscle symptoms (SAMS), which are the most common cause of statin intolerance. The aim of this study was to determine whether there is an association between polymorphisms 1236C > T, 2677G > T/A, and 3435C > T in the ABCB1 gene, encoding the efflux transporter of statins, and SAMS, as results on this topic are still controversial. A cross-sectional study was conducted on patients with or without SAMS using atorvastatin. The influence of non-genetic variables on SAMS was also evaluated. Our results show that patients with TT genotype in 1236C > T, 2677G > T/A, and 3435C > T polymorphisms had higher risk of developing SAMS, compared to wild type and heterozygous carriers together (OR 4.292 p = 0.0093, OR 5.897 p = 0.0023 and OR 3.547 p = 0.0122, respectively). Furthermore, TTT/TTT diplotype was also associated with a higher risk of SAMS, OR 9.234 (p = 0.0028). Only family history of cardiovascular disease was found to be a risk factor for SAMS, in addition to the known non-genetic variables. We believe that ABCB1 genotyping has great potential to be incorporated into clinical practice to identify high-risk patients in a timely manner.