A community-based evaluation of the effect of renal transplantation on survival in patients with renal-replacement therapy.

The relative effect of renal transplantation on survival was examined in chronic dialysis patients in Okinawa, Japan. Of 3,035 patients (1,722 men and 1,313 women) who were registered by the end of 1994 and followed up until April 1, 1995, 141 (91 men and 50 women) had undergone a renal transplantation during the follow-up period. The type of donor was a cadaver in 38 (26.9%) and a living relative in 103 (73.1%). At the end of the follow-up period, 12 (8.5%) of the patients with a renal transplant had died, 35 (24.8%) had returned to dialysis treatment, and 94 (66.7%) were alive with a functioning graft. In the patients who did not receive a transplant, 1,134 (39.2%) had died and 1,760 (60.8%) were alive and on dialysis. Cox proportional hazard analysis was performed with adjustment for sex, age at first dialysis, presence of diabetes mellitus, year of first dialysis, and predialysis co-morbid conditions. The hazard ratio (95% confidence interval) in the group with a transplant was 0.33 (0.18 to 0.59) when the hazard ratio of the group without a transplant was taken as 1.00. The patient survival rate was better in the former group. Our data provide fundamental evidence supporting the effectiveness of renal replacement as treatment. Whether the life-saving merit of renal transplantation is substantial enough to actively encourage donation remains to be clarified.

An epidemiologic analysis of parathyroidectomy in chronic dialysis patients. The Okinawa Dialysis Study Group.

Parathyroidectomy (PTX) is one of the treatments of choice for secondary hyperparathyroidism in chronic dialysis patients. Due to the large increase in long-term dialysis patients, hyperparathyroidism is becoming a common clinical problem. Several studies on PTX have reported various surgical procedures, but limited information is available on the incidence and risk factors of the surgery. The Okinawa Dialysis Study (OKIDS) registry is a community-based dialysis registry. It covers the entire area of Okinawa from when the use of chronic dialysis began in 1971. By the end of 1990, a total of 1,986 chronic dialysis patients were registered and 128 of these had undergone PTX by the end of 1993. The cumulative incidence of PTX was 4.3 in DM and 15.2 in non-DM per 1,000 patient-years. About half of the PTX patients underwent the surgery within 10 years of dialysis. By logistic analysis, the risk of PTX was seen to increase significantly with the duration of dialysis, P < 0.0001. Other clinical variables such as sex, age at the start of dialysis and the presence of diabetes mellitus were not significant predictors of PTX. The probability of PTX increased linearly with the duration of dialysis (r = 0.83, p < 0.0001). After the introduction of active vitamin D in 1981, the probability of PTX was significantly decreased (p < 0.05) compared to the pre-vitamin D period ('71-'80). With prolongation of the duration of dialysis, the risk of PTX increased steadily and was estimated to be 10 percent in 10 years and 20 percent in 20 years. Other uremic factors determining a pathological transformation of parathyroid tissue from reactive to autonomous growth remained to be investigated.

A PMN-derived factor that enhances DNA-synthesis in PHA or antigen-stimulated lymphocytes.

The DNA synthesis potentiation of a mouse polymorphonuclear leukocyte (PMN) factor was studied by using phytohemagglutinin (PHA)-stimulated syngeneic thymocytes. The partially purified PMN factor was nonmitogenic and exhibited maximum potentiation of thymocytes when added within 3 hr of PHA stimulation. PHA-stimulated, but not nonstimulated thymocytes absorbed PMN potentiation factor. 125I-labeled factor binding to stimulated thymocytes was observed. Our results suggest that an acceptor site for PMN factor may be generated on the thymocyte surface only after PHA stimulation.

Effect of renal diseases and comorbid conditions on survival in chronic dialysis patients.

International and geographical differences in the survival rates of chronic dialysis patients can be explained by differences in primary renal disease, in the acceptance rate of elderly patients, and in predialysis comorbid conditions. Several studies have shown the effects of these factors on survival. However, in most studies, a large number of patients may leave for renal transplantation or transfer to other centers, so that precise analysis becomes impossible. Although the number of patients in our registry is not so large (n = 1,982), we have few such problems and were able to examine the effects of the above-mentioned factors on patient survival using the Cox proportional hazard model. Hazard ratios (HR) and 95% confidence intervals were 0.739 and 0.366-1.491 in patients with polycystic kidney disease (n = 38), 2.669 and 1.513-4.708 in patients with systemic lupus erythematosus (n = 39), 1.245 and 0.935-1.660 in patients with nephrosclerosis (n = 122), 1.815 and 1.447-2.229 in patients with diabetes mellitus (n = 374), and 1.595 and 1.201-2.117, respectively, in patients with other renal diseases (n = 146) when the HR in patients with chronic glomerulonephritis (n = 1,263) was taken as 1.00. HR and 95% confidence intervals were 1.222 and 1.016-1.470 in patients with one comorbid condition (n = 217) and 1.494 and 1.033-2.160, respectively, in patients with two comorbid conditions (n = 24) when the HR of patients with no predialysis comorbid conditions (n = 1,741) was taken as 1.00. Our data demonstrate the effects of renal diseases and number of predialysis comorbid conditions on the survival in chronic dialysis patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Epidemiologic analysis of diabetic patients on chronic dialysis.

We retrospectively surveyed all of the available medical records of 404 (191 females and 213 males) chronic dialysis patients, of whom 16 (4%) had insulin-dependent diabetes mellitus (IDDM) and 388 (96%) non-insulin-dependent diabetes mellitus (NIDDM). The patients were among 2,214 dialysis patients in Okinawa, Japan, of whom 443 were diabetic. The patients entered a large population-based dialysis registry. The mean duration from the diagnosis of diabetes mellitus (DM) to dialysis was 181.6 months in the IDDM patients and 150.4 months in the NIDDM patients. The NIDDM patients were classified into four subgroups according to their status when DM was first suspected. The duration from the diagnosis of DM until the onset of dialysis treatment was significantly shorter than in any other subgroup or in the IDDM subgroup with major vascular disease (131.9 months). Otherwise, the course of renal disease in NIDDM patients was similar to that in IDDM individuals. Most of our dialysis patients with DM had NIDDM. In most of the NIDDM patients, the diagnosis had been delayed for several years for unknown reason. However, if diagnosed early, NIDDM shows a clinical time course until dialysis similar to that of IDDM. Whether NIDDM patients contract chronic renal disease at an equal incidence to that of IDDM patients and the fraction of all diabetic patients accepted for chronic dialysis remain to be determined.

An epidemiologic analysis of end-stage lupus nephritis.

We analyzed 566 patients (515 females and 51 males) with systemic lupus erythematosus who were treated in Okinawa, Japan, from 1972 to 1991 and followed until April 1993. One hundred four patients (95 females and 9 males) died, and 51 were considered to have end-stage lupus nephritis. The annual incidence and prevalence, per million population in each sex, were increased from 16.0 and 66.0 in 1972 to 46.7 and 683.9 in 1991 in the female patients, and from 4.2 and 8.3 in 1973 to 8.3 and 70.0 in 1991 in the male patients, respectively. Cox proportional hazard analysis was done to determine the effects of several covariates on patients and renal survival. The patients' survival rate improved, as the hazard ratio (HR) was decreased to 0.69 (year of diagnosis, 1982 to 1986) and to 0.48 (year of diagnosis, 1987 to 1991) when the HR in patients diagnosed before 1981 was taken as 1.00. Similarly, we examined renal survival by using the Cox proportional model. For this analysis, the date of start of dialysis therapy was regarded as the time of renal death. Male patients had significantly poor renal survival; the HR was 3.64 (95% confidence interval, 1.89 to 6.98) when the HR in the females was taken as 1.00. However, age at diagnosis and year of diagnosis did not significantly affect renal survival. The cumulated incidence of end-stage lupus nephritis from the time of diagnosis of systemic lupus erythematosus was 3.1% at 5 years, 9.4% at 10 years, 15.5% at 15 years, and 21.0% at 20 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Impact of the initial levels of laboratory variables on survival in chronic dialysis patients.

Besides the age at start of dialysis and the presence of diabetes mellitus, serum albumin has been shown to be a significant predictor of survival in prevalent dialysis patients. However, this was not evaluated in incipient dialysis patients. The initial biochemical variables were retrieved for a large dialysis population (N = 1,982) who were started on chronic dialysis in Okinawa, Japan from 1971 to 1990. Biochemical data that included blood urea nitrogen, serum creatinine, serum electrolytes (sodium, potassium, calcium, and phosphate), total cholesterol, triglyceride, total protein, serum albumin, and hematocrit obtained just before the first dialysis session were available for 1,491 (75.2%) patients. Six hundred sixty-four (43.2%) patients died by the end of 1993. Cox proportional analysis adjusted for sex, age, year of start of dialysis, presence of diabetes mellitus, and the laboratory variables was performed to examine the significance of the initial biochemical data on survival. The risk ratio was 0.577 (P = 0.0025) in serum albumin, 1.291 (P = 0.0138) in serum potassium, and 0.966 (P = 0.0202) in serum sodium. The study results support the notion that nutritional status is important for survival in chronic dialysis patients. Causes of hypoalbuminemia, hyperkalemia, and hyponatremia should be evaluated carefully at initiation of dialysis.

Increased risk of cardiovascular disease with erythropoietin in chronic dialysis patients.

Recombinant human erythropoietin is widely used in chronic dialysis patients. However, the long-term effect, especially on the incidence of cardiovascular disease, has not been critically evaluated. We observed the annual incidence of stroke and acute myocardial infarction from April 1988 through March 1993 in Okinawa, Japan. Until April 1990, erythropoietin was not generally used. Therefore, we have two periods: pre-erythropoietin, April 1988 through March 1990, and post-erythropoietin, April 1990 through March 1993. Two thousand one hundred and sixteen patients (1,219 males and 897 females) were on chronic dialysis during the study period by March 31, 1993. Every case of stroke and acute myocardial infarction during the study period was registered. The odds ratio was calculated using the data of the general population in each sex and age class obtained in the same area. A total of 86 cases of stroke and 15 cases of acute myocardial infarction were registered during the study period. The annual incidence, per 1,000 patient-years, of stroke was 12.5 (1988), 10.5 (1989), 12.7 (1990), 14.0 (1991), and 17.5 (1992). The incidence of stroke was increased in the post-erythropoietin period compared to the pre-erythropoietin period, odds ratio 1.22 and 95% confidence interval (95% CI 1.06-1.41, p < 0.01). The annual incidence of acute myocardial infarction was 1.0 (1988), 1.8 (1989), 0.8 (1990), 2.9 (1991) and 4.7 (1992). The incidence of acute myocardial infarction was increased significantly in the post-erythropoietin period compared to the pre-erythropoietin period, odds ratio 1.87 (95% CI 1.66-2.10, p < 0.01). The odds ratio of stroke to the general population was 4.25 (95% CI 3.10-5.82) in the pre-erythropoietin and 4.58 (95% CI 2.14-9.80) in the post-erythropoietin period. In acute myocardial infarction, it was 2.98 (95% CI 2.84-3.12) and 3.81 (95% CI 3.18-4.56). The odds ratio of acute myocardial infarction was significantly increased (p < 0.01). The introduction of erythropoietin was associated with an increased risk of cardiovascular disease, especially acute myocardial infarction. Erythropoietin may unmask the sclerotic lesion in chronic dialysis patients.

Low diastolic blood pressure, hypoalbuminemia, and risk of death in a cohort of chronic hemodialysis patients.

In a previous report, we showed that nutritional status and especially serum albumin had great predictive value for death in chronic hemodialysis patients, whereas blood pressure did not. In the present study, we analyzed the causes of death in consideration of the relationship between serum albumin and blood pressure. A total of 1,243 Okinawan patients (719 males, 524 females) undergoing hemodialysis in January 1991 were followed up through the end of 1995. Three hundred forty-two of the patients died, 45 received transplants, and 12 were transferred by the end of the follow-up period. The total duration of observation was 5,110.3 patient-years. Blood pressure as well as clinical and laboratory variables were determined immediately prior to the first dialysis session in January 1991. The crude death rate was 40.0% when the diastolic blood pressure (DBP) <70 mm Hg, 35.0% at 70 to 79 mm Hg, 25.0% at 80 to 89 mm Hg, 25.0% at 90 to 99 mm Hg, and 13.0% at >100 mm Hg. The death rate showed an inverse correlation with DBP. DBP showed a significant positive correlation with serum albumin (r = 0.137, P < 0.001) and age (r = -0.325, P < 0.0001). The adjusted odds ratio (95% confidence interval) of death was 0.84 (0.71 to 0.99) with 10 mm Hg increments in DBP when the reference DBP was less than 69 mm Hg. Low DBP may be a manifestation of malnutrition and/or cardiovascular disease in chronic hemodialysis patients. Target DBP levels may be higher levels in chronic hemodialysis patients than the general population.