Background: Microalbuminuria (MA) is the earliest clinical evidence of diabetic nephropathy, but most patients in sub-Saharan Africa (SSA) only have access to much cheaper dipstick proteinuria as a means to screen for diabetic nephropathy. The aim of this study was to determine the prevalence and associations of MA among proteinuria-negative type 2 diabetic patients in a SSA setting.
Methods: In this cross-sectional study, patients with type 2 diabetes screened negative for dipstick proteinuria in a primary healthcare hospital were assessed. Detection of microalbuminuria was carried out in two steps: qualitative detection using special microalbumin urine strip, and quantitative laboratory measurement and calculation of urinary albumin-to-creatinine ratio (UACR). Microalbuminuria was defined as UACR of 30-300 mg/g.
Results: A total of 162 type 2 diabetic patients were included. Using quantitative assessment, the prevalence of microalbuminuria was 14.2% (95% CI 8.8-19.6) whereas 26.5% (95% CI 19.8-34.0) had microalbuminuria with urine strip. The mean systolic blood pressure (p = 0.032), diastolic blood pressure (p = 0.032) and serum creatinine concentration (p < 0.001) were higher in people with microalbuminuria as compared to those with normoalbuminuria, whereas the mean body mass index (p = 0.046) and mean eGFR (p < 0.001) were lower in the albuminuria group. In multiple linear regression, eGFR (p = 0.001) and serum creatinine concentration (p = 0.003) were independently associated with increased UACR.
Conclusions: One in every seven proteinuria-negative type 2 diabetic patients has microalbuminuria in primary care setting in Cameroon; microalbuminuria is associated with higher systolic and diastolic blood pressure, and declining kidney function. Our results emphasize the urgent need to increase the accessibility to microalbuminuria testing to ensure that all diabetic patients with negative dipstick proteinuria can benefit.
Keywords: Cameroon; Diabetes; Diabetic nephropathy; Glomerular filtration rate; Microalbuminuria.