Emergence and Progression of Albuminuria in a Cohort of Egyptian Patients with Type 2 Diabetes Mellitus: a 5-year Prospective Study

Abstract

Introduction: We sought to report the 5-year incidence of proteinuria and risk factors for the progression of diabetic nephropathy in Egyptians with type 2 diabetes mellitus (DM). Methods: Five-hundred and twelve Egyptians with type 2 diabetes were evaluated at baseline and after 5-years of follow-up by a timed urine sample to measure urinary albumin excretion. Baseline evaluation also included a number of potential risk factors of progression of diabetic nephropathy. Results: Patients mean age was 47.5±8.8 years and 47.6% of them were males. Their mean duration of diabetes was 8.9±6.6 years and 44.1% of them were on insulin. At baseline, 62.5% of patients had no proteinuria, 23% had microalbuminuria and 14.5% had overt proteinuria. Among patients that had no albuminuria at baseline, 173/320 still had no albuminuria after 5-years follow up (54.1%), 79/320 developed microalbuminuria (24.7%) and 68/320 developed macroalbuminuria (21.3%). Microalbuminuria progressed to macroalbuminuria in 44/118 patients (37.3%), and 45/512 patients developed end stage renal disease (8.8%). Regression from microalbuminuria to no albuminuria occurred in 49/118 patients (41.5%), regression from overt proteinuria to microalbuminuria occurred in 16/74 patients (21.6%) and regression from overt proteinuria to no albuminuria occurred in 2/74 patients (2.7%). In multivariate analysis, only higher baseline albumin excretion rate (OR 1.4, P < 0.002), higher blood cholesterol levels (OR 2.5, P < 0.02), and depression (2.3, P <0.04) remained independently associated with new-onset proteinuria. Conclusions: In this group of Egyptians with type 2 diabetes, the 5-year incidence of proteinuria is high. Baseline AER is the strongest predictor for incidence of any proteinuria.