Table 1.

Spectrum of statin-associated muscle symptoms (based on 2014 National Lipid Association Task Force¹³)

Terms	Descriptions	Histopathological findings
Myalgia	Muscle discomfort with normal CK	None
Myopathy	Muscle weakness	Variable findings: Atrophy Inflammation Mitochondrial changes
Myositis	Muscle inflammation	T cells > B cells; macrophages
Myonecrosis	CK elevation >three-fold baseline (mild), ≥10-fold baseline (moderate), or ≥50-fold baseline (severe)	Non-specific inflammatory cells with secondary macrophage infiltration
Myonecrosis with myoglobinuria (rhabdomyolysis)	As above, plus increase in serum creatinine ≥0.5 mg/dL	Non-specific inflammatory cells with secondary macrophage infiltration

CK, creatine kinase.