Prospective randomized trial comparing relapse rates in dogs with steroid-responsive meningitis-arteritis treated with a 6-week or 6-month prednisolone protocol

Background

Traditionally, 6-month courses of prednisolone are used to treat steroid-responsive meningitis-arteritis (SRMA), but this medication is associated with adverse effects that can lead to poor quality of life.

Hypothesis/Objectives

Resolution of clinical signs and rate of relapse of SRMA would not be significantly different between a 6-month prednisolone protocol and a 6-week protocol.

Animals

Forty-four hospital cases from multiple referral centers in the United Kingdom (2015-2019). Twenty of 44 were treated with the 6-month protocol and 24/44 with the 6-week protocol.

Methods

Prospective, randomized trial with 12-month follow-up. The same prednisolone protocol reinitiated in the event of relapse. Analysis of relapses with binary logistic and Poisson regression modeling.

Results

All cases responded to their treatment protocol. Relapses occurred in 6/20 (30%) of the 6-month protocol and 9/24 (38%) of the 6-week protocol. There was no statistical difference in the incidence risk of at least 1 relapse between the 2 groups (odds ratio = 1.40; 95% confidence interval [CI], 0.40-4.96, P = 0.60). Among the 15 dogs that relapsed, 10/15 (67%) relapsed once, 3/15 (20%) relapsed twice, and 2/15 (13%) relapsed 3 times. No statistical difference was detected in the incidence rate ratio (IRR) of total relapse events between the 2 groups (IRR = 1.46; 95% CI, 0.61-3.48; P = 0.40).

Conclusions and Clinical Importance

“Short” 6-week prednisolone protocols could be used to treat SRMA, thereby presumably reducing the duration and severity of prednisolone's adverse effects.