Effect of statins therapy on glycemic control among type 2 diabetic patients attending University of Gondar Comprehensive Specialized Hospital, Gondar, Northwestern Ethiopia: A retrospective cohort study

Abstract

Abstract Background: Despite statins’ indispensable role in the prevention and delay of cardiovascular disorders, there are conflicting results on the effect of statins on glycemic control and on the risk of developing incidence type 2 diabetes. Objective: The aim of the study was to investigate the effects of statins therapy on glycemic control among type 2 diabetic patients attending University of Gondar Comprehensive Specialized Hospital (UOGCSH), Gondar, Northwestern Ethiopia. Method: A hospital-based retrospective cohort study conducted from March 20 to May 1, 2018 on medical records of patients with type 2 diabetes mellitus (T2DM) attending chronic follow up clinic of UOGCSH between March 2011 and April 2018. Descriptive statistics was used to summarize socio-demographic and other clinical characteristics. Further, a non-parametric test of Mann-Whitney U test and X VII

2 test (or a Fisher’s exact) were utilized to illustrate intergroup comparisons in the study. Kaplan-Meier and a logrank test

was used to plot the survival analysis curve. Cox proportional hazards model was instituted to examine the overall effect of statin use on glycemic control. A 5% level of significance was used. All of the analyses were performed using SPSS version 20 (IBM Corp., Armonk, NY). Result: A total of 390 patients were included in the final analysis (195 statin users and 195 statin non-users). Though not significant, the median last fasting blood glucose (FBG) was found to be higher in statin users (by 11 mg/dl) compared to the non-users. Likewise, median of the change in FBG (FBG at last minus initial) was 10 mg/dl in statin users compared with -1 mg/dl in non-statin users. A difference of 11 mg/dl was noted between median of the change in FBG of the two groups (P=0.013). Moreover, statin users had a significantly shorter survival probability over time than non-statin users (X 2 = 29.974; df = 1; P=0.000). Regarding the predictors, high intensity statin use were significantly associated with poor glycemic control [AHR (95% CI) = 2.428 (1.191-4.951), P=0.015] compared to non-statin use. Conclusion: The study concluded that statin therapy was associated with the rise of FBG levels over time in T2DM patients and in particular, high intensity stains were linked with poor glycemic control. Generally, the current study highly insist clinicians not to stop statins but to be cognizant of this potential adverse association of statin use on FBG/glycemic control and ensure close monitoring of blood glucose. Keywords: Ethiopia, Glycemic control, Statins, T2DM, UOGCSH