Are Chronic Pain Syndromes the Reason for Statin-associated Muscle Symptoms?

Background: Statin-induced myalgia is defined as muscle pain without elevation of serum creatine phosphokinase levels and is a well-known complaint among statin users. Chronic pain syndromes affect a high percentage of the population. These pain syndromes may confound the reports of statin-induced myalgia.

Objectives: To compare the occurrence of chronic pain among patients on statin therapy who developed myalgia with those who did not.

Methods: This study included 112 statin-treated patients, who were followed at the lipid center at Sheba Medical Center. Fifty-six patients had a diagnosis of statin-associated muscle symptoms (SAMS) and 56 did not. Verified questionnaires were used to assess the diagnoses of fibromyalgia, pain intensity, functional impairment, anxiety, and depression in the study population.

Results: Patients with statin myalgia were more likely to fulfil the diagnostic criteria for fibromyalgia than patients without statin myalgia (11 [19.6%] vs. 0, respectively). Patients in the SAMS group exhibited higher levels of anxiety and depression compared with the control group. Female sex, higher scores on the Brief Pain Inventory pain intensity scale, and a Hamilton rating scale level indicative of an anxiety disorder were found to be significant predictors for fibromyalgia in patients presenting with statin myalgia.

Conclusions: A significant percentage of patients diagnosed with statin myalgia fulfilled the diagnostic criteria for fibromyalgia depression or anxiety disorder. Detection of these patients and treatment of their primary pain disorders or psychiatric illnesses has the potential to prevent unnecessary cessation of effective statin therapy.