if considering statins to decrease recurrence risk--risk uncovrng neuromusclr disease

[Lani]

Statins May Unmask Underlying Neuromuscular Disease



NEW YORK (Reuters Health) Jul 26 - Patients with asymptomatic neuromuscular disorders may have their condition precipitated by statin use, according to investigators from the University of Athens Medical School.

Dr. Panagiota Manta and colleagues describe four such cases in the July 24th issue of the Archives of Internal Medicine.

Case 1 was a 46-year-old man with a history of hypertension and diabetes mellitus who was prescribed pravastatin for hypercholesterolemia. Three months later, he complained of fatigue, muscle pain and stiffness. Serum creatine kinase levels were persistently elevated. After stopping the drug, creatine kinase levels fell somewhat and there was mild symptom improvement. Mild myopathy was seen on needle electromyography and muscle biopsy showed numerous internal nuclei, nuclear clumps and variations in fiber size. Genetic testing revealed myotonic dystrophy.

Case 2 was a 62-year-old man with a history of MI and diabetes. Hypercholesterolemia was treated with simvastatin. Creatine kinase levels became persistently elevated and did not return to normal after drug discontinuation. Biopsy was positive for muscle enzyme activity. He was eventually diagnosed with McArdle disease.

Case 3 was a 51-year-old man with hypertension and hypercholesterolemia who was hospitalized with acute rhabdomyolytis after taking atorvastatin for 18 months. Exercise intolerance and muscle pain persisted for months after discontinuation of statin therapy. Some time later, he was diagnosed with mitochondrial myopathy.

The last case was a 58-year-old man with a history of hypertension, hyperuricemia and coronary artery disease. He began treatment with pravastatin. Shortly after a dose increase, he developed muscle twitching, muscle cramps and difficulty walking. Like the other cases, there was only mild symptom improvement and a modest decline in creatine kinase levels after the statin was discontinued. He was eventually diagnosed with Kennedy disease.

Statin-induced neuropathy is well recognized and reported more and more often, Dr. Manta's group notes. These four cases show that statins can also trigger underlying neuromuscular conditions.

The investigators suggest that if neuromuscular symptoms persist after discontinuation of statin therapy, clinicians should "pursue further diagnostic evaluations for the detection of underlying neuromuscular disease."

Arch Intern Med 2006;166:1519-1524.