Diabetes mellitus comorbidity in patients enrolled in tuberculosis drug efficacy trials around the world: A systematic review

AIMS: With a prevalence of 16%, diabetes mellitus (DM) is one of the most frequent non‐communicable comorbidities of tuberculosis (TB). DM is a major risk factor for adverse TB outcomes and may require personalized TB drug dosing regimens. However, information on the inclusion of DM in TB drug trials is lacking. We aimed to assess the percentage of recent TB drug efficacy trials that included DM patients. METHODS: A systematic review was performed and reported according to PRISMA guidelines. PubMed, Science Direct, and ClinicalTrials.gov databases were systematically searched for TB drug trials published between 1 January 2012 and 12 September 2017. Primary outcome was the percentage of TB drug trials performed around the world that included DM patients. RESULTS: Out of the included 41 TB drug trials, 12 (29.3%) reported DM comorbidity among the study participants. Nine trials (21.9%) excluded all patients with DM comorbidity, ten (24.4%) excluded only insulin‐dependent or uncontrolled DM, and 10 (24.4%) did not mention whether DM was included or excluded. Of the 12 trials that included DM comorbidity, the majority did not report the diagnostic criteria for DM and none reported outcomes in the DM subpopulation. Inclusion of DM was higher in drug‐resistant‐TB trials (67%, P = .003, vs drug‐susceptible) and trials performed in Asia (60%, P = .006, vs Africa). CONCLUSIONS: Fewer than 1/3 recent TB drug trials reported the inclusion of DM. To better reflect real‐world DM prevalence and differential TB drug effectiveness, inclusion of DM patients requires increased attention for future TB drug trials.