Role of Thyroid Disease in the Development of Statin-Induced MyopathyRush, Jordan MD*; Danzi, Sara PhD†; Klein, Irwin MD‡Author Information *Medical Student, Department of Medicine, North Shore University Hospital and Feinstein Institute for Medical Research, Manhasset, New York; †Assistant Professor, Department of Medicine North Shore University Hospital and Feinstein Institute for Medical Research, Manhasset, NY and Department of Medicine, NYU School of Medicine, NY; and ‡Professor, Department of Medicine, North Shore University Hospital and Feinstein Institute for Medical Research, Manhasset, NY and Departments of Medicine and Cell Biology, NYU School of Medicine, NY. Dr. Danzi has disclosed that she was a recipient of grant/research support from Roche and was a consultant/advisor for Roche and King Pharmaceuticals, Inc. Dr. Danzi is currently a recipient of grant/research support from King Pharmaceuticals, Inc. and is a consultant/advisor of King Pharmaceuticals, Inc. Dr. Klein has disclosed that he was a recipient of grant/research support from Roche, and was a consultant/advisor to Roche, King Pharmaceuticals, Inc., Chemical & Industrial Hygiene, Inc., Karo Bio, and Titan Corporation. Dr. Klein is currently a recipient of grant/research support from King Pharmaceuticals, Inc. and a consultant/advisor to King Pharmaceuticals, Inc., Titan Corporation, and Karo Bio. Dr. Rush has disclosed that he has no significant relationships with or financial interests in any commercial company that pertains to this educational activity. Lippincott Continuing Medical Education Institute, Inc. has identified and resolved all faculty conflicts of interest regarding this educational activity. This work was funded in part by an American Thyroid Association Grant in Aid to S. Danzi. Reprints: Irwin Klein, MD, North Shore University Hospital, 350 Community Drive, Manhasset, NY 11030. E-mail: [email protected] Chief Editor’s Note: This article is the 29th of 36 that will be published in 2006 for which a total of up to 36 AMA PRA Category 1 Credits™ can be earned. Instructions for how credits can be earned precede the CME Examination at the back of this issue. The Endocrinologist: September/October 2006 - Volume 16 - Issue 5 - pp 279-285 doi: 10.1097/01.ten.0000240960.40281.2b Buy Take the CME Test Metrics Abstract Hypothyroidism is a common endocrine disease, which, in addition to its classic signs and symptoms, can present with primary complaints of myopathy. Myopathy can cause skeletal muscle weakness, tenderness, and pain and is often associated with elevated creatine kinase levels. There are many neuromuscular causes of myopathy, including inflammatory and infectious myopathies, metabolic and hereditary myopathies, and those caused by drugs or toxins. Hypothyroid patients with musculoskeletal symptoms can have elevated serum creatine kinase levels, which clinically resemble polymyositis. However, hypothyroid myopathies can be distinguished from polymyositis by coexisting signs and symptoms of hypothyroidism such as delayed relaxation phase of the deep tendon reflexes and the absence of inflammatory changes on muscle biopsy. The treatment of hypothyroidism with thyroid hormone replacement will alleviate symptoms of myopathy as well as lower the characteristic hyperlipidemia associated with hypothyroidism. Hypercholesterolemia, which can arise from different etiologies, is frequently treated with a class of HMG-CoA reductase inhibitors called statins. One of the most significant risks associated with the use of statins is the development of myopathy, a risk that may be compounded by the coexistence of hypothyroidism. The underlying metabolic mechanisms that account for muscle disease in these 2 settings show some common etiologies. The overlap of symptoms associated with hypothyroidism and statin-induced myopathy should prompt the physician to screen all patients presenting with myopathic symptoms with or without elevated creatine kinase levels and all hyperlipidemic patients before initiating statin therapy for hypothyroidism using a measurement of thyroid-stimulating hormone. © 2006 Lippincott Williams & Wilkins, Inc.