A new systematic review published in the Annals of Internal Medicine today may provide the strongest evidence yet in favor of providing corticosteroids to those stricken with severe community-acquired pneumonia (CAP).

CAP, a broad term for cases of pneumonia (lung inflammation) that are picked up from outside the confines of a hospital, is one of the most prevalent medical conditions worldwide. Caused by a wide variety of bacteria, viruses and other infectious agents, CAP can range in severity from mild to life-threatening, though it is particularly difficult to treat in developing countries. One of the most common causes of CAP, the bacterium Streptococcus pneumoniae, alone resulted in the deaths of 1.6 million people in 2005, according to the World Health Organization .

In cases of CAP that require hospitalization, there’s been an active debate about the usefulness of providing corticosteroids, which reduce inflammation but have a laundry list of side-effects, including a weaker immune system, in addition to the standard course of treatment. Some studies have found benefits in reducing mortality rates or the length of treatment, but others have come up empty.

This latest analysis, reviewing 13 previous studies, sought to establish a firmer consensus.

“For hospitalized adults with CAP, systemic corticosteroid therapy may reduce mortality by approximately 3%, need for mechanical ventilation by approximately 5%, and hospital stay by approximately 1 day,” they concluded. They were also less likely (8 percent compared to 2 percent) to experience acute respiratory distress syndrome, a condition where the lungs begin to fill up with fluid and which is oftentimes fatal or permanently debilitating.

Relatively small but crucial as these benefits are, the authors believe they are more than enough to shift the thinking on steroid therapy for CAP.

"Our study should lead to an important change in treatment for pneumonia," said lead author, Dr. Reed Siemieniuk, a physician and a graduate student at McMaster University, in a statement . "Corticosteroids are inexpensive and readily available around the world. Millions of patients will benefit from this new evidence."

In an accompanying editorial published by the Annals, authors Dr. Marcos Restrepo, Dr. Antonio Anzueto, and Dr Antoni Torres applaud the rigorousness of the analysis but note that there remains work to be done in figuring out the optimal standard of steroid therapy, especially considering the different manifestations of CAP.

“The authors noted that the included studies used various agents, routes of administration, and doses,” they wrote. “These factors will need to be disentangled in future well-designed, randomized, controlled trials.”

One such trial, the Extended Steroid in CAP(e) study , is already in the pipeline. The Phase 3 study, sponsored by the Department of Veterans Affairs, is testing the effects of the glucocorticoid methylprednisolone on the survival rates of those with severe CAP. Actively recruiting participants now, it is set to be completed by January 2018.

In the meantime, the current study authors hope that their results will be enough to encourage an improved approach to the treatment of CAP.

"Seldom do we see a major advance in treatment of a condition as common as community-acquired pneumonia," said senior author Dr. Gordon Guyatt, a professor of clinical epidemiology and biostatistics at McMaster. "Corticosteroids over short periods are safe, and we now know that they achieve important benefits in a serious and common medical illness."

Source: Siemieniuk R, Meade M, Alonso-Coello P, et al. Corticosteroid Therapy for Patients Hospitalized With Community-Acquired Pneumonia: A Systematic Review and Meta-analysis. Annals of Internal Medicine. 2015.