What is tuberculous meningitis and how might corticosteroids work?
Tuberculous meningitis is a serious form of tuberculosis that affects the meninges that cover the brain and spinal cord, causing headache, coma and death. The clinical outcome is often poor even when people with tuberculous meningitis are treated with antituberculous drugs.
Corticosteroids are commonly used in addition to antituberculous drugs for treating people with the condition. These drugs help reduce inflammation of the surface of the brain and associated blood vessels, and are thought to decrease pressure inside the brain, and thus reduce the risk of death. Some clinicians are concerned that corticosteroids may improve survival, but result in more severely disabled survivors.
What the evidence shows
We examined the evidence published up to 18 March 2016 and included nine trials with 1337 people that evaluated either dexamethasone, methylprednisolone, or prednisolone given in addition to antituberculous drugs; one trial was of high quality, while the other trials had uncertainties over study quality due to incomplete reporting.
The analysis shows that corticosteroids reduce the risk of death by a quarter at two months to two years after treatment was started (high quality evidence). Corticosteroids make little or no difference to the number of people who survive TB meningitis with brain damage causing disability (low quality evidence); because this event is uncommon, even taking the most pessimistic estimate from the analysis of a slight increased risk with corticosteroids means this would not be quantitatively important when compared to the reduction in deaths.
One trial followed up participants for five years, by which time there was no difference in the effect on death between the two groups, although the reason for this change over time is unknown.
Only one trial evaluated the effects of corticosteroids in human immunodeficiency virus (HIV)-positive people but the number is small so we are not sure if the benefits in terms of fewer deaths are preserved in this group of patients.
Corticosteroids reduce mortality from tuberculous meningitis, at least in the short term.
Corticosteroids may have no effect on the number of people who survive tuberculous meningitis with disabling neurological deficit, but this outcome is less common than death, and the CI for the relative effect includes possible harm. However, this small possible harm is unlikely to be quantitatively important when compared to the reduction in mortality.
The number of HIV-positive people included in the review is small, so we are not sure if the benefits in terms of reduced mortality are preserved in this group of patients.
Tuberculous meningitis is a serious form of tuberculosis (TB) that affects the meninges that cover a person's brain and spinal cord. It is associated with high death rates and with disability in people who survive. Corticosteroids have been used as an adjunct to antituberculous drugs to treat people with tuberculous meningitis, but their role has been controversial.
To evaluate the effects of corticosteroids as an adjunct to antituberculous treatment on death and severe disability in people with tuberculous meningitis.
We searched the Cochrane Infectious Diseases Group Specialized Register up to the 18 March 2016; CENTRAL; MEDLINE; EMBASE; LILACS; and Current Controlled Trials. We also contacted researchers and organizations working in the field, and checked reference lists.
Randomized controlled trials that compared corticosteroid plus antituberculous treatment with antituberculous treatment alone in people with clinically diagnosed tuberculous meningitis and included death or disability as outcome measures.
We independently assessed search results and methodological quality, and extracted data from the included trials. We analysed the data using risk ratios (RR) with 95% confidence intervals (CIs) and used a fixed-effect model. We performed an intention-to-treat analysis, where we included all participants randomized to treatment in the denominator. This analysis assumes that all participants who were lost to follow-up have good outcomes. We carried out a sensitivity analysis to explore the impact of the missing data.
Nine trials that included 1337 participants (with 469 deaths) met the inclusion criteria.
At follow-up from three to 18 months, steroids reduce deaths by almost one quarter (RR 0.75, 95% CI 0.65 to 0.87; nine trials, 1337 participants, high quality evidence). Disabling neurological deficit is not common in survivors, and steroids may have little or no effect on this outcome (RR 0.92, 95% CI 0.71 to 1.20; eight trials, 1314 participants, low quality evidence). There was no difference between groups in the incidence of adverse events, which included gastrointestinal bleeding, invasive bacterial infections, hyperglycaemia, and liver dysfunction.
One trial followed up participants for five years. The effect on death was no longer apparent at this time-point (RR 0.93, 95% CI 0.78 to 1.12; one trial, 545 participants, moderate quality evidence); and there was no difference in disabling neurological deficit detected (RR 0.91, 95% CI 0.49 to 1.69; one trial, 545 participants, low quality evidence).
One trial included human immunodeficiency virus (HIV)-positive people. The stratified analysis by HIV status in this trial showed no heterogeneity, with point estimates for death (RR 0.90, 95% CI 0.67 to 1.20; one trial, 98 participants) and disability (RR 1.23, 95% CI 0.08 to 19.07; one trial, 98 participants) similar to HIV-negative participants in the same trial.