The effect of a steroid "burst" and long-term, inhaled fluticasone propionate on adrenal reserve.

Background: Although widely used, the effects of steroid "bursts" on the hypothalamic-pituitary-adrenal axis, especially with long-term, concomitant topical steroids use, have not been studied.

Objective: To examine the effect of a prednisone burst, long-term intranasal steroids, and inhaled fluticasone propionate on the suppression and recovery of adrenal function.

Methods: Adult patients taking long-term intranasal steroids, either moderate-dose (440 microg/d) or high-dose (880 microg/d) inhaled fluticasone propionate, underwent a low-dose cosyntropin stimulation test (LDCST) before and 2 days after a prednisone burst. Suppressed adrenal responses were monitored with a weekly LDCST. Persistent abnormal LDCST results were confirmed by 8-hour cosyntropin infusion. Inhaled fluticasone dosages were decreased; adrenal recovery was evaluated by a monthly LDCST. Adverse effects of steroids were monitored by questionnaires.

Results: Sixty-three patients participated in the study. Three of 31 patients not taking inhaled steroids and 1 of 13 patients taking moderate-dose fluticasone had abnormal LDCST results on day 2 after the prednisone burst, which normalized by the second week. In the high-dose fluticasone group, 14 of 19 patients had suppressed LDCST responses on day 2 and adrenal function recovered in 10 of 19 patients by the fourth week. These patients complained significantly of decreased libido (P = 0.02), listlessness (P = 0.03), and weight loss (P = 0.05). High-dose fluticasone (r = 0.66, P < 0.001) and duration of use (r = 0.32, P = 0.01) were statistically correlated with adrenal impairment. Of the 4 patients with persistent adrenal impairment, 3 patients successfully reduced dosages of inhaled fluticasone and adrenal function recovered in 2 to 10 months.

Conclusions: Prednisone bursts induce brief adrenal impairment. Intranasal steroids and moderate-dose fluticasone had no effect on adrenal function. High-dose, inhaled fluticasone caused mild-to-significant adrenal suppression and delayed the recovery after a steroid burst. Avoiding or limiting the duration of high-dose inhaled steroids would minimize systemic adverse effects.