Use of HBA1c and potentiality of gender, missed medication and fasting glucose in the prediction of poor glycemic control in resource-limited setting; a clinic-based case-control study

Abstract

INTRODUCTION: Diabetes Mellitus (DM) type 2 is a rapidly growing health problem in the world especially in resource limited countries. Even with availability of affordable medication still a large proportion of patients don´t attain a well-controlled glycemic state thus putting them at high risk of morbidity and mortality due to irreversible complications. Availability of glycated hemoglobin test (HBA1c) for better monitoring of glycemic control is still a setback in most resource restricted setting including Tanzania. This study was designed to determine the magnitude of uncontrolled DM type 2 using HBA1c and assess the utility of different factors in sorting patients at high risk of having uncontrolled DM in a clinic based setting in north western Tanzania. METHODS: this was a case control study involving diabetes type 2 patients at Bugando Medical Centre. A cross sectional measurement of glycated hemoglobin (HBA1c) and fasting glucose were done, medical history and adherence status to anti diabetes were assessed. Data analysis was done using STATA 13. Uncontrolled Diabetes was defined as an HBA1c of more than 7.0 and its correlates were assessed by logistic regression model. The predictive ability of independent variables was determined by calculating their sensitivity and specificity. RESULTS: in total 229 patients were included in this study, where 114 (49.8%; 95%CI: 43.3-56.3) had uncontrolled DM2 by HBA1c. In this study uncontrolled DM was independently associated with female gender, (AOR: 2.1; 95%CI: 1.1-3.9; p=0.022), frequently missed medications (AOR: 1.1; 95%CI: 1.03-1.2; p=0.006), and higher fasting median blood glucose, (10.5 vs. 6.9; AOR: 7.3; IQR: 3.7-14.7; P<0.001). Fasting glucose had higher predictive values to uncontrolled DM2 (sensitivity: 79.0%; 95%CI: 70.3-86.0; specificity: 84.4%; 95%CI: 76.4-90.4, cut point: 8.5; area under ROC curve: 0.8584)as compared to gender and missed medications. CONCLUSIONS: uncontrolled DM type 2 is common in Notherwestern Tanzania, and is well predicted by fasting hyperglycemia. Fasting hyperglycemia can be used in selecting patients that could benefit from timely intensification of treatment where HBA1c is not available.