Determinants of diabetic nephropathy among adult type II diabetic patients attending Kenyatta National Hospital; A Case-Control study

Abstract

Background: Diabetic nephropathy (DN) is the most serious sequelae resulting from uncontrolled T2DM and a great predictor of end-stage renal disease (ESRD) globally. Despite several studies having explored determinants associated with its occurrence, there is a paucity of data in the African region, especially in Kenya evidenced by scarce published data. With the steady rise of T2DM, its complications, such as DN are expected to rise. Objective: To elucidate factors associated with the occurrence and progression of DN among adult T2DM patients at Kenyatta National Hospital (KNH), Nairobi, Kenya. Methods: Hospital-based case-control study was conducted. Diabetes patients seeking care at KNH Diabetic clinic were the source population. Adult T2DM patients, ≥18 years with established diabetic nephropathy (outcome), evidenced by increased urinary albumin (>30mg/d) for at least six months and/or estimated glomerular filtration rate (eGFR) of <60 ml/min/1.73m2 were the cases. Diabetic patients free from established diabetic nephropathy and, ≥18 years were the controls of the study. All cases meeting the case definition and eligibility criteria were recruited and the control group was recruited by systematic random sampling within the study period to achieve a sample of 395, (the case-to-control ratio being 1:3) 99 cases and 296 controls. Data collection on socio-demographics, behavioral, medical history/biomedical, and healthcare system factors were collected through patient records review and interviewer-administered questionnaire, in form of ODK (Open Data Kit) software. Analysis and results: Data was cleaned in excel and then exported to SPSS vs 27 for analysis. descriptive statistics were used to summarize continuous data while for categorical variables, percentages and proportions were used. In assessing the association between predictor variables on the response variable, univariable and multivariable logistic regression analyses were conducted. Significance levels were then determined at p-value (p<0.2) in the univariable analysis and (p<0.05) in the multivariable analysis. In the univariable analysis, age, well-managed blood pressure, diabetic diet adherence, exposure to nephrotoxins, duration of living with diabetes, ACE/ARB inhibitors use, diabetic retinopathy complication, positive family history of diabetic nephropathy, the perception that diabetes nutritional guidelines are ineffective, and inefficient healthcare system showed significant association with DN. In the multivariable analysis, well-managed BP (aOR 0.43; 95% CI: 0.20-0.91), nephrotoxin exposure (aOR 10.04; 95% CI: 3.15-31.96), duration since diagnosis of DM (aOR 0.06; 95% xiii CI: 0.02-0.19), family history of DN (aOR 52.67: 95% CI: 13.11-211.64), the perception that nutritional guidelines are ineffective in delaying the development and progression of DN (aOR 17.52; 95% CI 7.09-43.31), and the perception that healthcare system at KNH is inefficient (aOR57.14; 95%; CI 8.70-398.18) significantly showed association with diabetic nephropathy. Conclusion In this study, well-managed Bp, nephrotoxin exposure, duration since diagnosis of DM, family history of DN, the ineffectiveness of diabetes nutritional guidelines, and healthcare system inefficiency were found to be major predictors of DN. With these findings, efforts towards reversing trends of type 2 diabetes should be made with a focus on curtailing complications such as DN. This can be achieved by blood pressure management, sensitization on the proper use of NSAIDs and herbal medicine, improved lifestyle for those with a family history of DM and DN, strict diabetic diet adherence as well as more studies using more rigorous scientific methods be carried out to identify determinants of diabetic nephropathy.