Epidemiology of chronic renal failure in Iran: a four year single- center experience.

Chronic renal failure (CRF) is a major public health problem. Early diagnosis and proper management have important roles in prevention of CRF progression to end-stage renal disease (ESRD). For this purpose, determining the etiology of CRF may be helpful. This study was conducted in the nephrology department at the Mostafa Khomeini Hospital in Tehran, Iran from March 2001 to March 2005, to determine the etiology of CRF in adult Iranian patients. A total of 1200 patients with a diagnosis of CRF were involved in the study. Relevant data were collected using a reliable questionnaire. All data analyses were carried out using SPSS and the chi2 test. Of the 1200 patients, 61% were males and 39% females. The most frequent age group was 61-75 years (38.3%) and the mean age of the study patients was 51.6 +/- 17 years. The etiology of CRF in our series included: diabetes mellitus in 26.8%, hypertension in 13.5%, obstructive uropathy in 12%, cystic and congenital disorders in 10.3%, glomerulonephritis in 6.5%, urinary tract infections in 4%, vasculitis in 2%, tubulo-interstitial nephritis and pregnancy related in 0.8% each and unknown causes in 29.5% of the patients. Laboratory and ultrasonographic assessment at initiation of the study revealed blood urea nitrogen> 100 mg/dl in 57.8% of the patients, serum creatinine> 10 mg/dl in 40.3%, glomerular filtration rate (GFR) < 10 ml/min in 61.3%, hemoglobin < 10 g/dl in 65.8% and kidney size lesser than 8 cm in 46% of the cases. There was a significant statistical relationship between kidney size and duration of hypertension greater than five years (P = 0.017). The high frequency of CRF of unknown etiology in this study may be attributed to diagnostic limitations prevailing in our country. A GFR of < 10 ml/min in 61.3% of the cases at presentation suggests late diagnosis and/or referral. Aggressive screening and treatment strategies to prevent ESRD are recommended.