Low plasma vitamin D levels and muscle-related adverse effects in statin users

Treatment with HMG-CoA reductase inhibitors (statins) is often complicated by muscle-related adverse effects (MAEs). Studies of the association between low plasma vitamin D levels and MAEs have yielded conflicting results.

To determine if low plasma vitamin D level is a risk factorfor MAEs in statin users.

Plasma levels of 25(OH) vitamin D were measured as part of the routine evaluation of unselected statin-treated patients attending the coronary and lipid clinics at our hospital during the period 2007-2010. Medical data on muscle complaints and statin use were retrieved from the medical files. Creatine kinase (CK) levels were derived from the hospital laboratory database.

The sample included 272 patients (141 men) aged 33-89 years. Mean vitamin D level was 48.04 nmol/L. Levels were higher in men (51.0 +/- 20.5 versus 44.7 +/- 18.9 nmol/L, P = 0.001) and were unaffected by age. MAEs were observed in 106 patients (39%): myalgia in 95 (35%) and CK elevation in 20 (7%); 9 patients (3%) had both. There was no difference in plasma vitamin D levels between patients with and without myalgia (46.3 +/- 17.7 versus 48.9 +/- 21.0 nmol/L, P = 0.31), with and without CK elevation (50.2 +/- 14.6 versus 47.8 +/- 20.3 nmol/L, P = 0.60), or with or without any MAE (50.4 +/- 15.0 versus 47.8 +/- 10.2 nmol/L, P = 0.27). These findings were consistent when analyzed by patient gender and presence/absence of coronary artery disease, and when using a lower vitamin D cutoff (< 25 nmol/L).

There is apparently no relationship between plasma vitamin D level and risk of MAEs in statin users.