Objective: While osteoporosis and bone fractures are clearly recognized side effects of high dose glucocorticoids, the effect of low dose glucocorticoids remains controversial. We investigated the effect of 3 months of low dose hydrocortisone on bone mineral density (BMD).
Methods: Subjects, 18 to 55 years old with chronic fatigue syndrome and no medical or psychiatric illness requiring medication, were randomized in a double blind, placebo controlled trial to receive oral hydrocortisone, 13 mg/m2 body surface area every morning and 3 mg/m2 every afternoon (25 to 35 mg/day, equivalent to about 7.5 mg prednisone/day) or placebo for 12 weeks. Before and after treatment BMD of the lumbar spine was measured by dual energy x-ray absorptiometry.
Results: We studied 23 subjects (19 women, 4 men). For the 11 hydrocortisone recipients there was a mean decrease in BMD: mean change from baseline of the lateral spine was -2.0% (95% CI -3.5 to -0.6. p = 0.03) and mean change of the anteroposterior spine was -0.8% (95% CI -1.5 to -0.1, p = 0.06). Corresponding changes for the 12 placebo recipients were +1.0% (95% CI -1.0 to 3.0, p = 0.34) and +0.2% (95% CI -1.4 to 1.5, p = 0.76).
Conclusion: A 12 week course of low dose glucocorticoids given to ambulatory subjects with chronic fatigue syndrome was associated with a decrease in BMD of the lumbar spine. This decrease was statistically significant in lateral spine measurements and nearly so in anteroposterior spine measurements.