Efficacy of Dexamethasone for Acute Primary Immune Thrombocytopenia Compared to Prednisolone: A Systematic Review and Meta-analysis

Abstract

Corticosteroids have been established as first-line therapy in acute primary immune thrombocytopenia (ITP), and the clinical guidelines recommend either dexamethasone (Dex) or prednisolone (PSL). The types and dosages of corticosteroids, however, have not yet been determined, because previous randomized control trials (RCTs) comparing Dex and PSL showed controversial results in terms of efficacy. To understand and interpret all available evidence, we conducted a systematic review and meta-analysis of RCTs. The main outcome measure was the incidence of sustained response (SR; platelet count >30 × 10 ⁹ /L for 6 months without concomitant treatments after the completion of the final therapies). Eight RCTs (totaling 704 patients) were included in this study. The incidence of SR showed no significant difference, while it was significantly higher in the Dex arm when used with posttherapy (more than one course of Dex or tapering corticosteroids added; risk ratio [RR], 1.82; 95% confidence interval [CI], 1.38-2.41; p < 0.01). A single course of Dex showed no significant difference. The overall response (platelet >30 × 10 ⁹ /L) at day 28 was significantly improved in the Dex arm (RR, 1.11; 95% CI, 1.01-1.22; p = 0.03) and Dex with posttherapy suppressed long-term relapse (RR of nonevent, 1.32; 95% CI, 1.10-1.59; p < 0.01). There were significantly fewer adverse events in the Dex arm (RR, 0.45; 95% CI, 0.37-0.55; p < 0.01). Use of Dex with posttherapy instead of PSL may be more beneficial as the initial therapy. Studies comparing Dex with other new strategies are essential to determine the most suitable therapeutic regimens for acute ITP.

Keywords: dexamethasone; meta-analysis; prednisolone; thrombocytopenia.

Fig. 1

Forest plots of long-term sustained response (SR) comparison. The summary effect estimate (risk ratio [RR] of SR at 6 months; platelet counts > 30 × 10 ⁹ /L) for individual randomized controlled trials (RCTs; dexamethasone [Dex] vs. prednisolone [PSL]) are indicated with black boxes (their sizes are proportional to the study weight), with the lines indicating 95% confidence intervals (CIs). The overall summary effect estimate (RR) and 95% CI are indicated by the diamond below. ( a ) SR in all the RCTs and ( b ) subgroup analyses (Dex with posttherapy and Dex monotherapy).

Fig. 2

Forest plots of short-term overall response (OR), complete response (CR), and relapse comparison. The summary effect estimate (risk ratio [RR] of overall response [OR; platelet counts > 30 × 10 ⁹ /L] and complete response [CR; platelet counts > 100 × 10 ⁹ /L] at 28 or 14 days after the initial therapy) for individual randomized controlled trials (RCTs; dexamethasone [Dex] vs. prednisolone [PSL]) are indicated with black boxes (their sizes are proportional to the study weight), with the lines indicating 95% confidence intervals (CIs). The overall summary effect estimate (RR) and 95% CI are indicated by the diamond below for OR at 28 days ( a ) and 14 days ( b ), and CR at 28 days ( c ). Risk ratio of nonevent regarding posttherapeutic relapse (loss of response or bleeding episodes) was indicated in all RCTs ( d ) and in each subgroup regarding the addition of posttherapy in the Dex arm ( e ).