Predictors of switching from nonsteroidal anti-inflammatory drugs to corticosteroids in patients with acute pericarditis and impact on clinical outcome

Background: Aspirin and nonsteroidal anti-inflammatory drugs (A/NSAIDs) are the mainstay treatments for acute pericarditis. We sought to identify factors predicting failure of A/NSAIDs and switch to corticosteroid treatment (STCT) as well as the impact of STCT on pericarditis recurrence. Methods: We enrolled 148 patients with acute pericarditis receiving A/NSAIDs (n=110) or corticosteroids (n=38) as first-line treatment according to clinical indications. In case of poor response to A/NSAIDs (n=37), STCT was performed and factors contributing to such failure were explored. All patients were followed-up prospectively for 18 months for pericarditis recurrence. Results: In multivariate analysis, female sex (odds ratio [OR] =3.57, 95% confidence interval [CI]: 1.00-12.5), age (per decade, OR=0.75, 95% CI: 0.57-0.99), PR-segment depression (OR=4.43, 95% CI: 1.02-19.34), and a secondary cause of pericarditis (OR=13.52, 95% CI: 1.51-117.8) were independent predictors of poor response to A/NSAIDs and STCT. In cox regression analysis, the risk of recurrence was higher in patients requiring STCT (hazards ratio [HR] =3.22, 95% CI: 1.70-6.13) and in those initially treated with corticosteroids (H=2.06, 95% CI: 1.01-4.21) than in patients receiving A/NSAIDs only. Conclusions: Treatment failure with A/NSAIDs in acute pericarditis can be anticipated by certain patient characteristics. STCT identifies patients who are at the highest risk for recurrences, a risk that is approximately threefold higher than that of A/NSAIDs and 1.5-fold higher than that of corticosteroids as first-line treatment. Keywords: Acute pericarditis, Prognosis, Nonsteroidal anti-inflammatory drugs, Corticosteroids, Treatment failure