The steroids-induced myopathy
Myopathy is a condition wherein muscle fibers do not normally function due to certain reasons. This condition results to muscle weakness, muscle cramps, stiffness and spasm.
In a study conducted by several Australian endocrinologists, they found that myopathy in steroids treatment may result from the effects of steroids on the androgen level, androgen receptors and the insulin-like growth factor 1 (IGF-1).
The study employed non-diabetic and diabetic patients at St. Vincent’s hospital in Melbourne, Australia. The participants were given a daily dose of 4 mg Dexamethasone for four continuous days. It resulted to a decrease in the skeletal muscle-androgen receptors and plasma testosterone levels to as much as 30% or more.
Decrease in plasma testosterone level will result to a decreased muscle function of the skeletal muscle tissues. It may also result to a negative effect on skeletal muscle cells enlargement.
Dr. Warwick Inder and colleagues also reported a rise in the plasma IGF-1. There was no difference observed in the testosterone levels between non-diabetic and diabetic patients. The plasma glucose levels, however, were observed to be slightly higher in the diabetic group.
The similar effect on plasma testosterone levels on both men and women suggested that muscle integrity is affected with glucocorticoid therapy on both genders.
From the Endocrinology update:
Muscle weakness associated with glucocorticoid therapy may result from the direct effects of steroids on circulating androgen levels, androgen receptors in muscle, and IGF-1, Australian endocrinologists report.
