Increased Incidence of Cerebral Hemorrhage Mortality in Patients with Analgesic Nephropathy on Hemodialysis

Dr. A. Chachati, Hôpital de Bavière, Institut de Médecine B, 66, bd de la Constitution, B-4020 Liège (Belgium) Dear Sir, Analgesic nephropathy (A) is a serious problem in Belgium with an incidence of 18,4% of patients with end-stage renal failure [1]. We wish to report here a retrospective autopsic analysis of 75 hemodialyzed patients: 12 with A and 63 with nonanalgesic nephropathy (NA). The results of this study showed a significantly higher incidence of cerebral hemorrhage as a cause of death (table I) in the A group: 25%) (3/12) as compared to 3%) (2/63) in the NA group. (Yates corrected χ2 = 4.43, p < 0.025). The mean age at death of patients was comparable in both groups: 51 ± 12 years in the A and 56 ± 11 years in the NA group. Female preponderance, as already described [2], was observed in the A group with a female/male ratio of 75% as compared to 38% in the NA group (χ2 = 5.57, p < 0.025). In order to explain the reasons of such a higher incidence of cerebral hemorrhage, various autopsic (left ventricular thickness, aortic and coronary atherosclerosis appreciated macroscopically – (score 0–5) -‚ presence of acute or healed myocardial and cerebral infarction) and clinical parameters (blood pressure before and during hemodialysis treatment and analysis of the clinical causes of death of patients with A on hemodialysis dying during the same period, but not autopsied) were compared in each group. First, the analysis of the blood pressure levels prior to the start of hemodialysis treatment showed no difference between both groups in the relative number of patients presenting hypertension (74% in the A vs. 83% in the NA group), in the severity (17% of the A group patients presented a blood pressure > 200/120 mm Hg as compared to 18% in the NA group), and in the duration of hypertension (42% of the A group patients were known to have blood pressure levels > 160/95 mm Hg for at least 2 years as compared to 49%) in the NA group). Second the thickness of the left ventricle of the A group patients, measured at autopsy, showed values similar to that of the NA patients (1.90 ± 0.18 vs. 1.94 ± 0.18 cm). The relative percentage of analgesic patients presenting severe aortic atherosclerosis (score 4–5) Table I. Causes of death Causes of death NA