Epidemiology and Risks of Infections in Patients With Multiple Myeloma Managed With New Generation Therapies

Abstract

IntroductionTreatment for multiple myeloma (MM) has continued to evolve with second generation immunomodulatory drugs (IMiDs), proteasome inhibitors (PIs), and monoclonal antibodies (mAbs). This study aims to evaluate the epidemiology and risks of infection in patients with MM managed with these therapies. Patients and MethodsClinical and microbiological records were reviewed to capture patient demographics, disease characteristics, treatment received, episodes of infection, and outcomes. Infections were classified as microbiologically defined (MDI), clinically defined (CDI), and fever of unknown focus (FUF). Univariate and multivariate analyses were performed to determine risk factors for infection, with a P value < .05 considered statistically significant. ResultsA total of 148 patients with MM with 345 infection episodes were identified. Of these, 29.0% (100/345), 58.0% (200/345), and 13.0% (45/345) were defined as MDI, CDI, and FUF, respectively. Of 100 MDIs, 50.0% were owing to viruses, whereas 45.0% were owing to bacterial infection. The most common infection site was the respiratory tract (56.8%). Hospital admission occurred in 41.7% of infection episodes, and the 30-day all-cause mortality rate was 5.4%. On multivariate regression, receipt of a PI (odds ratio [OR], 16.80; 95% confidence interval [CI], 2.47-114.52), combination of IMiD and PI (OR, 13.44; 95% CI, 2.39-75.76), mAb-combination (OR, 10.44; 95% CI, 1.99-54.51), and lines of therapy (> 4) (OR, 7.72; 95% CI, 1.25-47.81) were associated with increased risk of infection (all P < .05). ConclusionViral infections now constitute the majority of infections in patients with MM treated with newer agents. Receipt of a PI and lines of therapy (> 4) were associated with higher risk for infection.