Endocrine Abstracts

Muscle symptoms are the most common side effects of statin therapy and reasons for its discontinuation. Low serum vitamin D may contribute to statin-associated muscle symptoms (SAMS). The aim was to investigate the relationship between occurrence of SAMS and level of vitamin D (D), determine predictors of SAMS.

Methods: 84 statin-treated patients were included in the study: 41 with SAMS (intolerant to ≥2 statins) and 43 patients without SAMS. We use SAMS clinical index (SAMS-CI) to determine SAMS. The vitamin D levels, parathyroid hormone (PTH), hematology and high sensitive protein (hsCRP) were performed.

Results: D was significantly lower (22.3±12.20 ng/ml and 37.53±10.21 ng/ml) and PTH was significantly higher (42.1±14.2 and 30.4±10.2 pg/l, P<.001) in patients with SAMS compared with those without SAMS. In 29% of patient with SAMS were observed vitamin D deficient (D<20 ng/ml) and 43% had an insufficient D (21–29 ng/ml), while only 7% of patient without SAMS had vitamin D deficient and 11% an insufficient D. In patients with SAMS levels hsCRP was significantly higher (P<.001) and hemoglobin (Hb) concentrations were 0.5 g/dL lower than in patients without SAMS (P<.05). Regarding D, mean Hb were 1.2 g/dL lower in vitamin D deficient category than in adequate D category (P<.001). In multivariable modelling we have found an excellent correlation between D and SAMS-CI, Hb and hsCRP (P<.001; P<.05; P<.05; respectively). The correlation between vitamin D and hsCRP was highly significant (r =-0.879, P<.001) in patients with SAMS and less significant in patients without SAMS (r=- 0.402, P<.05). It was shown that decreasing vitamin D levels are associated with increasing hsCRP levels (sign of inflammatory state) in non statin-treated patients. Age, D<25 ng/ml, Hb <12.5 g/dL and hsCRP >3 mg/l at baseline had modest discriminative powers for predicting SAMS (0.56, P<.01; 0.45, P<.01; 0.542, P<.001; 0.712, P<.001; respectively).

Conclusion: We found an inverse association between vitamin D level and a statin-induced muscle symptoms in statin-treated patients. The prevalence of vitamin D deficiency 29% and an insufficiency D 43% in patients with SAMS. A low vitamin D concentration is accompanied by microinflammatory state and anemia risk. Age, lower level of vitamin D and Hb, higher level of hsCRP were identified as potential predictors of statin associated muscle symptoms. So, assessment of vitamin D status may be useful for the diagnosis and management of SAMS, especially in older patients with Hb <12.5 g/dl and hsCRP >3 mg/l.