Takahiro Shinzato

Translation, cultural adaptation, and initial reliability and multitrait testing of the Kidney Disease Quality of Life instrument for use in Japan*

Background: The Kidney Disease Quality of Life instrument (KDQOL™) consists of 79 items: 36 asking about health-related quality of life (HRQOL) in general (the Medical Outcomes Study SF-36) and 43 asking about QOL as it is affected by kidney disease and by dialysis. Aim: Translation, cultural adaptation and initial reliability and multitrait testing of the KDQOL™ for use in Japan. Methods: Translation and cultural adaptation began with two translations into Japanese, two backtranslations into English, and discussions among the translators, the project coordinators in Japan, and the developers of the original (US-English) version. Focus-group discussions and field testing were followed by analyses of test–retest reliability, internal consistency, and convergent and discriminant construct validity. Results: All eight of the SF-36 scales met the criterion for internal consistency (Cronbachs α ranged from 0.73 to 0.92) and were reproducible (intraclass correlations between test and retest scores ranged from 0.60 to 0.82). Of the 10 kidney-disease-targeted scales, only two had α coefficients of less than 0.70: ‘sleep’ (0.61) and ‘quality of social interaction’ (0.35). One item on the ‘quality of social interaction’ scale had a very weak correlation with the remainder of that scale (r = 0.10). Eliminating that item from scoring increased the α coefficient of the scale from 0.35 to 0.64. All three items on the ‘quality of social interaction’ scale had very strong correlations with other scales. Conclusions: First, in Japanese patients receiving dialysis the SF-36 scales are internally consistent and their scores are reproducible. Second, with the possible exception of the ‘quality of social interaction’ scale, the Japanese version of the KDQOL™,can provide psychometrically sound kidney-disease-targeted data on quality of life in such patients.

An Overview of Regular Dialysis Treatment in Japan (as of 31 December 2004)

Abstract:  A statistical survey of 3932 nationwide hemodialysis (hereafter, dialysis) facilities was carried out at the end of 2004, and 3882 facilities (98.73%) responded. The population undergoing dialysis at the end of 2004 was 248 166, an increase of 10 456 patients (4.4%) from that at the end of 2003. The number of dialysis patients per million people was 1943.5. The crude death rate of dialysis patients from the end of 2003 to the end of 2004 was 9.4%. The mean age of patients who underwent dialysis in 2004 was 65.8 years, and that of the total dialysis population was 63.3 years. The percentage distribution of patients who underwent dialysis according to a newly underlying disease showed that 41.3% of patients had diabetic nephropathy and 28.1% had chronic glomerulonephritis. The frequency of calcium carbonate use for dialysis patients was 75.1% and that of sevelamer hydrochloride use was 26.2%. The frequency of sevelamer hydrochloride use does not necessarily have a strong correlation with the dose of calcium carbonate. Patients who received high doses of sevelamer hydrochloride tended to have a low concentration of arterial blood HCO3–. Approximately 15% of dialysis patients used an intravenous vitamin D preparation, generally maxacalcitol. The longer the patients had been on dialysis, the higher the frequency of use of an intravenous vitamin D preparation. When the concentration of serum intact parathyroid hormone (PTH) was more than 200 pg/mL, the frequency of use of an orally administered vitamin D preparation decreased; but that of intravenous vitamin D preparation increased. The percentage of dialysis patients who received percutaneous ethanol injection therapy (PEIT) was 1.4%. The percentage was more than 50% in the patients who had been on dialysis for more than 10 years. The percentage of patients who received PEIT again was 35.0%. The percentage of patients who had been on hemodialysis for more than 10 years and received PEIT again was more than 50%. 

Factors influencing long-term survival in patients on chronic dialysis

Japan has the highest prevalence of dialysis patients in the world. According to the Annual Report of the Japanese Society for Dialysis Therapy (JSDT; 2002), the total dialysis population was 229 538 (1801.5 patients per million population) at the end of 2002. The annual crude mortality rate has been less than 10%. Survival rates in the incident dialysis patients were 0.874 for 1 year, 0.609 for 5 years, and 0.391 for 10 years. Despite the increased acceptance for dialysis of elderly patients, those with comorbid conditions, and those with diabetes mellitus, the adjusted hazard ratios for death have been improving since 1983. This improvement was obtained by delivering a dialysis dose of Kt/V 1.33 and dialysis sessions of 4 h. Independently of the JSDT registry, there exists a local dialysis registry in Okinawa, the Okinawa Dialysis Study (OKIDS) registry, in which are filed the records of every chronic dialysis patient from the beginning of dialysis therapy in 1971 to the end of 2000. Several outcome studies have been conducted to determine the factors related to survival, using the data in that registry. There are distinct differences in environmental and socioeconomic conditions and lifestyles within a given country, and between countries and ethnic groups, that may affect the survival of dialysis patients. In this article, both the JSDT registry and OKIDS data are reviewed in order to identify factors related to the survival of chronic dialysis patients.

Induction of Irreversible Glomerulosclerosis in the Rat by Repeated Injections of a Monoclonal Anti-Thy-1.1 Antibody

The present experiment demonstrated that an irreversible glomerulosclerosis could be induced in the rat through repeated intravenous administrations of OX-7 (a monoclonal anti-Thy-1.1 antibody). Rats were injected with 0.2 mg of affinity-purified OX-7 at 1-week intervals for a period of 4 weeks. Glomerular damage was periodically examined at light-microscopic level. Thirty-five days after the initial injection (7 days after the final injection), capillary aneurysms and expansion of the mesangial areas with hypercellularity were frequently observed. Similar glomerular damage was also observed in rats 7 days after they received a single injection of either 1.0 or 0.2 mg of OX-7. After repeated injections, 112 days from the initial administration (84 days after the final injection), approximately 60% of the glomeruli had expanded mesangial areas with an apparent increase in the mesangial matrix. The result contrasts sharply with that obtained from a single injection of OX-7 in that more than 85% of the glomeruli showed no abnormalities 84 days after the injection. This chronic model, as a result of repeated injections of the antibody, could serve as a potential for further investigation of the mechanisms involved in the development of chronic glomerulonephritis.

Relationship between dialysis induced hypotension and adenosine released by ischemic tissue

Two types of dialysis induced hypotension apparently exist. One type presents as gradually decreasing blood pressure with eventual symptoms (gradual hypotension), whereas the other presents as abruptly and sharply decreasing blood pressure, along with symptoms (abrupt hypotension). In the current study, the authors found that the plasma hypoxanthine concentration during abrupt hypotension was significantly higher than before the hypotension occurred (20 min after saline was administered or at the beginning of dialysis), whereas comparison of the plasma hypoxanthine concentration during gradual hypotension and that before the hypotension occurred (20 min after saline was administered or at the beginning of dialysis) revealed no significant difference. The current results indicate that abnormally increased adenosine triphosphate (ATP) degradation associated with tissue ischemia occurred during abrupt hypotension but not during gradual hypotension. It can be speculated that the increased release of adenosine due to abnormally increased ATP degradation caused the abrupt hypotension. This conclusion seems reasonable given that adenosine directly decreases small vessel tone and inhibits prejunctional release of norepinephrine.

Prevalence and Determinants of Hypertension in Chronic Hemodialysis Patients in Japan

Abstract:  Hypertension is common in chronic hemodialysis (HD) patients. However, its prevalence and determinants have not been studied in a large HD population. We analyzed the database of the Japanese Society for Dialysis Therapy (JSDT) registry, which conducts an annual survey of chronic dialysis patients throughout Japan. We compiled those who were on HD three‐times per week and aged 20 years and over at the end of 2000 (JSDT standard analysis file 001). Hypertension was defined as predialysis systolic blood pressure (SBP) ≥140 mm Hg or predialysis diastolic blood pressure (DBP) ≥90 mm Hg. Adjusted odds ratios (95% confidence interval) for the determinants of hypertension were calculated by the multivariate logistic regression analysis. A total of 65 393 people (men, 60.2%; mean age ± SD, 60.9 ± 12.8 years; and mean duration of HD ± SD, 95.3 ± 74.0 months) were studied. Mean ± SD levels of SBP and DBP were 154.9 ± 23.8 mm Hg and 80.5 ± 13.7 mm Hg before the HD session. Hypertension was noted in 77.5% of patients. Prescription of antihypertensive drugs and erythropoietin was made to 60.7% and 82.0% of patients, respectively. Both SBP and DBP were higher in those who were prescribed antihypertensive drugs (mean, 160.4/81.9 mm Hg), than those without drugs (mean, 146.9/78.5 mm Hg) (in both cases P < 0.0001). Hypertension was positively associated with men (adjusted odds ratio (OR), 1.258; 95% confidence interval (CI), 1.188–1.333; P < 0.0001), age (OR, 1.004; CI, 1.001–1.006; P < 0.01), duration of HD (OR, 0.769; CI, 0.728–0.812; P < 0.0001), serum albumin (OR, 1.369; CI, 1.286–1.458; P < 0.0001), and change in body weight by dialysis session (ΔBW) (OR, 1.176; CI, 1.159–1.194; P < 0.0001), and was negatively associated with Kt/V (OR, 0.600; CI, 0.543–0.664; P < 0.0001), and hematocrit (OR, 0.964; CI, 0.959–0.970; P < 0.0001). The distribution of ΔBW was normal in shape and in about 22% of patients the range was from 4.0% to 4.9%. There was a significant positive relationship between the prevalence of hypertension and ΔBW (R2 = 0.8549). The higher the ΔBW, the more the prescription rate of antihypertensive drugs increased (R2 = 0.9102). Results showed that the prevalence of hypertension was significantly associated with volume excess and serum levels of albumin, calcium, and phosphorous in chronic HD patients. Despite the high prescription rate of antihypertensive drugs, control of blood pressure remains unsatisfactory.

Increasing gender difference in the incidence of chronic dialysis therapy in Japan.

Abstract:  The incidence of chronic kidney disease and its progression to end‐stage renal disease (ESRD) differs between genders, so it can be surmised that the incidence of ESRD is different between men and women. We analyzed the annual incidence of ESRD by gender for a 20 year period, from 1983 to 2002, using Japanese Society for Dialysis Therapy (JSDT) registration data. The annual incidence of ESRD was calculated as the number of incident dialysis patients divided by the census population of the previous year in each gender, and expressed per million of each population (male and female). In men, the incidence of ESRD increased from 99.9 in 1983 to 330.2 in 2002, whereas it was 66.6 in 1983 and 184.9 in 2002 in women. The difference of incidence of ESRD from men to women increased from 33.3 in 1983 to 145.3 in 2002. The mean age at the start of dialysis was 51.5 years (men) and 52.5 years (women) in 1983, it increased to 63.8 years (men) and 66.1 years (women) in 2002. The difference in mean age increased from 0.9 years in 1983 to 2.3 years in 2002. There was no clear relationship between the available dialysis station per 100 000 population and the men to women ratio in the prevalent dialysis patients among the 47 prefectures. The acceptance of dialysis therapy might not be strong enough to explain the increasing difference in ESRD incidence between men and women in Japan. Differences in the socioeconomic conditions and lifestyles between men and women, which might be related to the gender difference in incidence in ESRD, should be studied further.

Effects of L-Carnitine Administration on Short-Chain Fatty Acid (Acetic Acid) and Long-Chain Fatty Acid Metabolism during Hemodialysis

The purpose of the study is to investigate the effects of L-carnitine on the exogenous acetate metabolism during hemodialysis together with the triglyceride and free fatty acid metabolism. Sixteen chronic renal failure patients on acetate dialysis were orally administered 1,200 mg of L-carnitine chloride per day for 12 weeks. Plasma triglyceride concentrations at 30 and 60 min following initiation of hemodialysis were significantly lower than before hemodialysis, while the plasma concentrations of free fatty acid at the same points into hemodialysis were significantly higher than before hemodialysis, whether L-carnitine chloride was being given or not. This is attributed to the enhanced degradation of triglyceride and the increased generation of the free fatty acid with heparin administration during hemodialysis. The L-carnitine chloride treatment did not affect the plasma triglyceride concentrations at 30 and 60 min into hemodialysis, whereas the free fatty acid concentrations at the same points into hemodialysis were significantly lower after L-carnitine chloride administration commenced than before it. This is attributed to the fact that fatty acid oxidation was enhanced following the L-carnitine chloride treatment. Compared to before the drug administration, the whole body clearance of exogenous acetate was significantly increased after the drug was given, and the plasma acetate level during hemodialysis fell accordingly. This is attributed to the fact that with L-carnitine chloride administration, the amount of accumulated acyl-CoA in the cytosol decreased and consequently the citrate cycle function increased.

Deformity of Buttonhole Entry Site Causes Higher Frequency of Vascular Access-Related Infection.

BACKGROUND Vascular access-related infection is more frequent in patients using the buttonhole method for cannulation of the arteriovenous access for hemodialysis. Deformity of buttonhole entry sites is frequently observed among patients on the buttonhole method for extended periods of time. With deformed buttonhole entry sites, moreover, scabs are often incompletely removed at the time of buttonhole cannulation. METHOD In 166 patients using the buttonhole method at Hino Clinic in Osaka, Japan as of June 30, 2014, the shapes of buttonhole entry sites were categorized into the following 3 types: flat, depressive deformity, and bulging deformity. A multivariate logistic regression method was used to analyze associations between various data including shapes of buttonhole entry sites and occurrence of access-related infection. We also examined microscopic features of the buttonhole entry site tissue that was removed from a patient who died after 3 years of buttonhole cannulation. RESULTS For the flat buttonhole entry sites, frequency of access-related infection was 0.12 events/1,000 arteriovenous fistulas as compared to 0.47 events/1,000 arteriovenous fistulas for the entry sites with bulging deformity. Such infection did not occur for the entry sites with depressive deformity. The multivariate logistic regression analysis revealed a significant association between an entry site with bulging deformity and occurrence of access-related infection (odds ratio = 5.369, p = 0.0085). Furthermore, the microscopic section showed granulations beneath the skin at the buttonhole entry site and around the buttonhole tract. CONCLUSION A significant association was shown between an entry site with bulging deformity and occurrence of access-related infection. The microscopic features of the buttonhole entry site of the patient on the buttonhole method for 3 years suggest that the entity of bulging deformity at the entry site is hypertrophic granulation.

A New Method That Enables Complete Removal of Scabs at Buttonhole Entry Sites

BACKGROUND Scab removal is a time-consuming process and often injures the skin at a buttonhole entry site. Incomplete removal of scabs may cause access-related infection. METHODS In a new procedure, buttonhole entry sites were treated with a moist healing step after hemodialysis, and then a formed scab was wiped off with a microfiber towel during bathing on the night prior to hemodialysis, which was performed on the following day. In the moist healing step, the entry site was disinfected with a diluted povidone-iodine solution (0.1% povidone-iodine solution). RESULTS When the buttonhole entry sites of the patients were treated with the new procedure, the scabs had already been removed at the buttonhole entry sites, and the sites were covered with a thin transparent membrane. Histological examination showed the thin membrane was stratum corneum, in which nuclei are still seen in keratinocytes. CONCLUSION By treating the buttonhole entry sites of patients with the wound moist healing method and then rubbing the sites with a microfiber towel during bathing, scabs can be removed without injuring the skin at the sites in advance.