Prevalence and factors associated with microalbuminuria in type 2 diabetic patients at a diabetes clinic in northern Tanzania

The aim of this study was to determine the prevalence and factors associated with microalbuminuria in patients with type 2 diabetes attending the diabetes clinic at Kilimanjaro Christian Medical Centre in northern Tanzania. We enrolled 149 patients aged over 19 years. Three morning urine samples separated by a gap of 1 month each were analysed within a 6-month period. Urinary albumin concentration was measured by an immunoturbidimetric assay and two positive tests (urinary albumin excretion 30–300 mg/L) were considered as positive for microalbuminuria. The overall prevalence of microalbuminuria was 29%. Presence of microalbuminuria was significantly related to age, systolic blood pressure, use of angiotensin converting enzyme inhibitors or angiotensin receptor blockers, body mass index, fasting blood glucose, haemoglobin A1c level, serum creatinine, and creatinine clearance (p<0.05). However after a multivariate logistic regression only haemoglobin A1c, creatinine, and creatinine clearance were strongly associated with microalbuminuria. In conclusion, the study revealed a higher prevalence of microalbuminuria among people with type 2 diabetes, compared with another Tanzanian study in Dar es Salaam. Determination of the urinary albumin excretion is an easy method for screening of microalbuminuria, and is recommended for all diabetic patients even in low-resource settings, to provide optimum management to delay the progression to end-stage renal disease. Introduction Diabetes mellitus remains a tremendous challenge to public health worldwide. The estimated number of people living with diabetes in Africa is currently 12.1 million, but a recent projection showed that the number will reach 23.9 million by 2030.1 More than 482 000 East Africans Dr Sudakshina Ghosh and Dr Issack Alphonce Lyaruu, Department of Internal Medicine, Kilimanjaro Christian Medical Centre, Moshi, Tanzania; and Prof. Karen Yeates, Queen’s University, Kingston, Ontario, Canada. Correspondence to: Dr Sudakshina Ghosh, PO Box 3010, Kilimanjaro Christian Medical Centre, Moshi, Tanzania. Email: bishnusri04@yahoo.com. P.O. Box 3010, are now diagnosed with type 2 diabetes, Tanzania being the leading country with 201 000 among an estimated population of over 38 million.2 Diabetic nephropathy is the leading cause of end-stage renal disease (ESRD) worldwide.3 In Africa it is probably the third most common cause of chronic kidney disease after hypertension and glomerulonephritis. It also accounts for a third of all patients requiring renal replacement therapies, which are prohibitively expensive and not widely available in Africa due to cost and lack of expertise.4 Persistent urine albumin excretion of between 30 mg/ day and 300 mg/day (which is equivalent to 30–300 mg/L of a spot urine sample or 20–200 μg/min of a timed urine sample is defined as microalbuminuria (MA). It is the earliest clinical manifestation of nephropathy.5 MA is also a predictor for cardiovascular disease, one of the components of metabolic syndrome. Nephropathy is also a strong risk factor for diabetic retinopathy.6–8 However, previous studies have shown that unlike macroalbuminuria, MA can revert to normoalbuminuria in patients with diabetes when they are treated with agents known to protect the kidneys and reduce proteinuria.9 Despite the availability of therapies to reduce MA, people with diabetes are not routinely evaluated for MA in most low-resource sub-Saharan African settings, including our centre. With this knowledge our study objective was to detect the prevalence of MA and utilise this knowledge to implement measures which may delay the progression to ESRD and have a future impact on clinical practice guidelines for the management of patients with type 2 diabetes in Tanzania as a whole. Patients and methods This cross-sectional analytical hospital-based study was conducted among consecutively enrolled adults (>19 years) with type 2 diabetes attending the Diabetes Clinic at the Kilimanjaro Christian Medical Centre (KCMC) between August 2010 and February 2011. KCMC is one of the four referral hospitals in Tanzania and it serves a population of 15 million people. Patients with urinary tract infections, active heart failure and HIV infection were excluded from the study. Those subjects found to have overt proteinuria >300 mg/day by using urine dipsticks were also excluded. A total of 149 individuals