The routine use of steroids to treat tuberculosis may help reduce deaths from all types of the disease, according to a new review of existing research.
Each year there are 8.7million cases of TB worldwide, and it causes 1.4million deaths. The most common form of the disease (pulmonary TB) affects the lungs, but there are many other forms and it can affect almost all the body's organs.
Currently, steroids are routinely used only for certain types of TB - each of which affects a different organ system - where they have been proven effective as a secondary treatment alongside anti-TB drugs. Exactly how steroids help combat TB is not known, but they are believed to counter the tissue-damaging effect of the inflammatory response caused by the disease.
This latest research - which summarised the findings of existing studies from 1955 to 2012 on the effect of steroids on all types of TB - found that there were 17 per cent less deaths overall among patients taking steroids than those who were not. The study did not demonstrate a difference in death rates between different forms of TB.
The researchers say their findings suggest that steroids could work in a systemic way that is similar for all forms of the disease. Nevertheless, they say further studies are required before steroids should be recommended for all TB patients. Such studies should investigate if the reduced death rate is seen when looking at current TB drugs only, in studies with greater numbers of patients, and if the benefits of routinely prescribing steroids for all TB would outweigh the risk of harmful side effects. Potential side effects of steroid use include increased vulnerability to other infections.
The research was carried out by a team at St George's, University of London, in partnership with Newcastle University, the University of Liverpool and the Liverpool School of Tropical Medicine. It has been published in The Lancet Infectious Diseases.
The researchers analysed results from 41 previous major TB trials on the efficacy of corticosteroids - drugs based on hormones found in the adrenal gland, which are used to reduce inflammation. They looked at trials involving the five common forms of TB for which steroid trials had been conducted. The types of TB were pericarditis (affecting the heart), meningitis (the brain and spinal cord), peritonitis (the abdomen) and pleurisy (the membranes surrounding the lungs). In total, they examined information on 3,560 patients who took steroids and 2,982 who did not. The types of steroids, the doses and the duration of treatment varied.