Vol. 101, No. 4 Printed in U.SA.
AMERICAN JOURNAL OF EPIDEMIOLOGY
Copyright © 1975 by The Johns Hopkins University
AN EPIDEMIOLOGIC STUDY OF RENAL FAILURE II. ACUTE RENAL FAILURE1 HASKEL E. ELIAHOU, HAYIM BOICHIS, GUSTAVA BOTT-KANNER, VITA BARELL, NEORA BAR-NOACH AND BARUCH MODAN2 Eliahou. H. E., H. Boichis. G. Bott-Kanner, V. Barell, N. Bar-IMoach and B. Modan (Chaim Sheba Medical Center, Tel Hashomer, Israel). An epidemiologic study of renal failure. II. Acute renal failure. Am J Epidemiol 1 0 1 : 2 8 1 286, 1975.—A total community study of acute renal failure (ARF) was carried out in Israel. The mean annual incidence was 4.8/100,000, the risk being 50% higher in males than in females. It was found that ARF is due primarily to a multiplicity of factors and rarely to a single cause; the high mortality associated with ARF is related to the patient's basic underlying condition. The epidemiology of ARF results from a compilation of the various conditions leading to it, and would, therefore, vary according to the differential distributions of these conditions in the population. dialysis; epidemiology; kidney diseases; mortality; renal failure, acute; sex factors
A complete systematic epidemiologic study of acute renal failure (ARF) in an entire community has been lacking. The only population data available are those of Branch et al. (1) who studied the incidence of uremia in their catchment area. Sixteen patients with acute tubular necrosis in a period of two years were noted—an incidence of 67/106/year. However, an analysis of the complete spectrum of ARF has not been reported. The objectives of our study were: (a) to examine the distribution of Received for publication July 2, 1974, and in final form November 2, 1974. Abbreviation: ARF, acute renal failure. 1 From the Departments of Nephrology and Clinical Epidemiology, Chaim Sheba Medical Center, and Tel Aviv University Medical School. 2 Established Investigator of the Chief Scientist's Bureau, Ministry of Health Israel. Reprint requests to Dr. Modan, Chaim Sheba Medical Center, Tel Hashomer, Israel. The study has been supported by research agreement No. 06-817-2 from the U.S. Public Health Service. The authors express gratitude to Mrs. P. Zafnat, Mrs. S. Hatvani, Mrs. T. Stayer and Mrs. M. Weiner as well as to the Medical Record Librarians of all general hospitals in Israel for their invaluable aid in this study. They further thank Dr. Stanley Schor for his many helpful suggestions in the preparation of this report.
ARF in an entire community, (b) to attempt to determine possible etiologic factors, and (c) to evaluate the adequacy of treatment and causes of mortality. METHODS
Collection of data. This survey is part of a nationwide uremia study (2) based on a systematic screening of laboratory records in all general hospitals in Israel for the calendar years 1965 and 1966. Hospitalization records of all patients 60 years of age and younger, with at least one blood urea of 60 mg/100 ml or higher were comprehensively reviewed. Previous and subsequent hospitalizations, Outpatient Department, and other clinic records were also reviewed and summarized. Study population. In contrast with part I (2) which reported only on Jewish patients age 15-59, the current analysis refers to both Jewish and Arab patients less than one year old through age 60. Population data were based on the 1961 general census and subsequent estimates. Definitions. For the purpose of this study, ARF was defined as an acute onset of failure of kidney function in a patient
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who had no renal failure or insufficiency prior to the acute precipitating episode. Dialysis was considered "required" when the blood urea level was 250 mg/100 ml or more and/or the serum creatinine 10 mg/100 ml or more, or the serum potassium 7 mEq/L or more, or when hypercatabolism was present as evidenced by a daily rise in blood urea level of 60 mg/100 ml or more. Dialysis was considered "adequate" when, following its administration, the blood urea levels were reduced and maintained under 250 mg/100 ml, and the serum creatinine under 10 mg/100 ml, together with a rapid and sustained homeostasis. Conditions such as terminal metastatic cancer, massive injury of the brain and other fatal conditions were taken to preclude the need for dialysis. Criteria for case selection. Only ARF patients with a blood urea level of 200 mg/100 ml and above were included in the current analysis. In patients with lower, but still abnormal blood urea levels, renal failure is either a transient episode from which the patient may recover without benefit of hospitalization or is a terminal event with a minor role in the course of a lethal basic disorder. On the other hand, the group selected for analysis comprises the more severe cases that require active treatment including dialysis, and have a high probability of detection. Further details on case selection were given in part I of this report (2). Analysis of data. All records were independently reviewed by three nephrologists in order to verify the classifications, to determine the underlying cause leading to the renal failure, the requirement for and adequacy of dialysis given and the causes of death where it occurred. Deaths were divided into three categories: (a) death was directly attributable to uremia, (b) death was primarily due to a basic underlying disease, and (c) a pernicious basic disease was complicated by uremia that probably hastened death.
RESULTS
Incidence. Out of a total of 4453 records of patients with abnormal blood urea in the two-year period under study, 229 (5 per cent) were compatible with this study's criteria of ARF, yielding a mean annual incidence rate of 4.8/100,000 population age 60 and under. Age-specific incidence rates are presented in table 1 and manifest a marked bimodality with peaks at the extremes. The overall male to female ratio was 1.5:1.0, but this ratio was significantly reversed (p(x2)
AMERICAN JOURNAL OF EPIDEMIOLOGY
Copyright © 1975 by The Johns Hopkins University
AN EPIDEMIOLOGIC STUDY OF RENAL FAILURE II. ACUTE RENAL FAILURE1 HASKEL E. ELIAHOU, HAYIM BOICHIS, GUSTAVA BOTT-KANNER, VITA BARELL, NEORA BAR-NOACH AND BARUCH MODAN2 Eliahou. H. E., H. Boichis. G. Bott-Kanner, V. Barell, N. Bar-IMoach and B. Modan (Chaim Sheba Medical Center, Tel Hashomer, Israel). An epidemiologic study of renal failure. II. Acute renal failure. Am J Epidemiol 1 0 1 : 2 8 1 286, 1975.—A total community study of acute renal failure (ARF) was carried out in Israel. The mean annual incidence was 4.8/100,000, the risk being 50% higher in males than in females. It was found that ARF is due primarily to a multiplicity of factors and rarely to a single cause; the high mortality associated with ARF is related to the patient's basic underlying condition. The epidemiology of ARF results from a compilation of the various conditions leading to it, and would, therefore, vary according to the differential distributions of these conditions in the population. dialysis; epidemiology; kidney diseases; mortality; renal failure, acute; sex factors
A complete systematic epidemiologic study of acute renal failure (ARF) in an entire community has been lacking. The only population data available are those of Branch et al. (1) who studied the incidence of uremia in their catchment area. Sixteen patients with acute tubular necrosis in a period of two years were noted—an incidence of 67/106/year. However, an analysis of the complete spectrum of ARF has not been reported. The objectives of our study were: (a) to examine the distribution of Received for publication July 2, 1974, and in final form November 2, 1974. Abbreviation: ARF, acute renal failure. 1 From the Departments of Nephrology and Clinical Epidemiology, Chaim Sheba Medical Center, and Tel Aviv University Medical School. 2 Established Investigator of the Chief Scientist's Bureau, Ministry of Health Israel. Reprint requests to Dr. Modan, Chaim Sheba Medical Center, Tel Hashomer, Israel. The study has been supported by research agreement No. 06-817-2 from the U.S. Public Health Service. The authors express gratitude to Mrs. P. Zafnat, Mrs. S. Hatvani, Mrs. T. Stayer and Mrs. M. Weiner as well as to the Medical Record Librarians of all general hospitals in Israel for their invaluable aid in this study. They further thank Dr. Stanley Schor for his many helpful suggestions in the preparation of this report.
ARF in an entire community, (b) to attempt to determine possible etiologic factors, and (c) to evaluate the adequacy of treatment and causes of mortality. METHODS
Collection of data. This survey is part of a nationwide uremia study (2) based on a systematic screening of laboratory records in all general hospitals in Israel for the calendar years 1965 and 1966. Hospitalization records of all patients 60 years of age and younger, with at least one blood urea of 60 mg/100 ml or higher were comprehensively reviewed. Previous and subsequent hospitalizations, Outpatient Department, and other clinic records were also reviewed and summarized. Study population. In contrast with part I (2) which reported only on Jewish patients age 15-59, the current analysis refers to both Jewish and Arab patients less than one year old through age 60. Population data were based on the 1961 general census and subsequent estimates. Definitions. For the purpose of this study, ARF was defined as an acute onset of failure of kidney function in a patient
281
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ELIAHOU ET AL.
who had no renal failure or insufficiency prior to the acute precipitating episode. Dialysis was considered "required" when the blood urea level was 250 mg/100 ml or more and/or the serum creatinine 10 mg/100 ml or more, or the serum potassium 7 mEq/L or more, or when hypercatabolism was present as evidenced by a daily rise in blood urea level of 60 mg/100 ml or more. Dialysis was considered "adequate" when, following its administration, the blood urea levels were reduced and maintained under 250 mg/100 ml, and the serum creatinine under 10 mg/100 ml, together with a rapid and sustained homeostasis. Conditions such as terminal metastatic cancer, massive injury of the brain and other fatal conditions were taken to preclude the need for dialysis. Criteria for case selection. Only ARF patients with a blood urea level of 200 mg/100 ml and above were included in the current analysis. In patients with lower, but still abnormal blood urea levels, renal failure is either a transient episode from which the patient may recover without benefit of hospitalization or is a terminal event with a minor role in the course of a lethal basic disorder. On the other hand, the group selected for analysis comprises the more severe cases that require active treatment including dialysis, and have a high probability of detection. Further details on case selection were given in part I of this report (2). Analysis of data. All records were independently reviewed by three nephrologists in order to verify the classifications, to determine the underlying cause leading to the renal failure, the requirement for and adequacy of dialysis given and the causes of death where it occurred. Deaths were divided into three categories: (a) death was directly attributable to uremia, (b) death was primarily due to a basic underlying disease, and (c) a pernicious basic disease was complicated by uremia that probably hastened death.
RESULTS
Incidence. Out of a total of 4453 records of patients with abnormal blood urea in the two-year period under study, 229 (5 per cent) were compatible with this study's criteria of ARF, yielding a mean annual incidence rate of 4.8/100,000 population age 60 and under. Age-specific incidence rates are presented in table 1 and manifest a marked bimodality with peaks at the extremes. The overall male to female ratio was 1.5:1.0, but this ratio was significantly reversed (p(x2)
