Sobrevida em hemodiálise crônica: estudo de uma coorte de 1.009 pacientes em 25 anos

INTRODUCTION: Most patients with end-stage renal disease depend on hemodialysis (HD) for life maintenance. Analysis of factors influencing survival can assist in the continuous search for better results. METHODS: We analysed 1,009 patients treated with chronic HD in three dialysis units in the city of Santa Maria, RS, Brazil, for 25 years (1982-2007). RESULTS: Survival (Kaplan-Meier method) at 1, 2, and 5 years was 91%, 84%, and 64%, respectively. In Cox regression model, the variables with a statistically significant impact on mortality risk were: age at starting HD (increase of 4.5% per additional year; p = 0.0001), presence of diabetes (increase of 56%; p = 0.001), and year of beginning HD treatment (reduction of 5.2% for each subsequent year; p = 0.0001). Survival was significantly better for patients who started HD from 1997 to 2007 than for those who started from 1982 to 1996, for both diabetic (54% vs. 41% at 5 years; p = 0.01) and nondiabetic patients (72% vs. 65% at 5 years; p = 0.045), although nondiabetic patients were significantly older in the latter period. CONCLUSIONS: The presence of diabetes and each additional year in age led to significantly increased risk. Regarding the year of the beginning of the HD program, a significantly smaller risk was observed for each subsequent calendar year. The increase in survival achieved in more recent years was greater for diabetic and older patients. It was attributed to diagnostic and therapeutic improvements and better overall quality of the dialysis program.