Screening diabetes in tuberculosis patients in eastern rural China: a community-based cross-sectional study

To understand the prevalence of diabetes mellitus (DM) and tuberculosis (TB) comorbidity in rural China and to identify factors associated with TB-DM comorbidity and screening efficacy.

A community-based cross-sectional study was carried out in four counties in eastern rural China. All TB patients newly registered from April 2013 to March 2014 were screened for DM using fasting blood glucose (FBG). Screening-positive patients were further examined using glycosylated haemoglobin A1C (HbA1c).

Ninety-seven (7.7%) of the 1252 recruited TB patients had DM, 44 (45.4%) of whom were newly diagnosed. The DM-TB patients were significantly older than non-diabetics (mean age 57 ± 13 years vs. 49 ± 19 years, P < 0.001). The risk of DM-TB was higher in patients aged >40 years (OR 3.039) and in overweight patients (OR 2.595). The number needed to screen (NNS) among TB patients to identify one case of DM was 12.97. The NNS to identify one new DM patient (27.4) was lower in participants aged >40 years (20.5), those who were illiterate (19.9), those with a family history of DM (9.3), those with missing bacille Calmette-Guérin vaccination (11.3), current smokers (14.2) and those with body mass index >24 (11.4).

Regular DM screening in TB patients is practical in rural China. Better efficacy of DM-TB detection could be obtained by screening high-risk populations, such as overweight TB patients or those with a family history of DM.