Raised levels of IFN-gamma and IL-13 are associated with pre-diabetes amongst newly diagnosed patients with tuberculosis

Objective: To investigate pre-diabetes and diabetes in newly-diagnosed tuberculosis patients and to assess the association of serum cytokine levels with diabetes status. Methods: The cross-sectional study was conducted at Indus Hospital and The Aga Khan University Hospital, Karachi from May to November 2015, and included patients of either gender aged 18 years or more with a confirmed diagnosis of tuberculosis who were either newly diagnosed or had received up to 1 month of anti-tuberculosis therapy were included. Patients were enrolled from among those presenting to the clinics at Indus Hospital, Karachi, and the Department of Medicine, Aga Khan University Hospital (AKUH), Karachi. The patients were tested for glycosylated haemoglobin and random blood glucose. Diabetes was defined as HbA1c >6.5%; pre-diabetes as HbA1c=5.7-6.4%; and normoglycaemic as HbA1c <5.7%. Serum cytokines were investigated using the Bio-plex 27, Bio-Rad assay. SPSS version 19.0 was used for data analysis. Results: Of the 211 subjects, 110(52%) were females and 101(48%) were males. The overall median age of the sample was 26 years, and 100(47.3%) subjects were underweight. Of the total, 24(11.4%) had diabetes and 45(21.3%) had pre-diabetes. Of the diabetics, only 7(29%) knew their status prior to screening. Interferon-gamma and interleukin-13 were significantly different among tuberculosis patients with diabetes, pre-diabetes and normoglycaemia (p<0.05). Glycosylated haemoglobin levels showed a significant correlation with interferon-gamma levels. Conclusions: Raised interleukin-13 and interferon-gamma levels in newly-diagnosed tuberculosis patients with pre-diabetes.