Shinichiro Yoshi

Plasma Aldosterone in Hypertensive Patients on Chronic Hemodialysis: Distribution, Determinants and Impact on Survival

A high plasma aldosterone concentration (PAC) is known to be associated with poor outcome in patients with cardiac disease. However, the prognostic value of PAC in chronic hemodialysis (HD) patients is unknown. In 1996 we examined 128 hypertensive patients treated with antihypertensive drugs, excluding angiotensin-converting enzyme inhibitors, who were undergoing chronic HD (ages 61.8±13.8 years, 62% male), and for whom PAC (ng/dl) data were obtained. We followed up these patients until November 2003. During the follow-up period, 30 patients died. About half of all patients (48%) had PAC values above the normal range. We assigned the 128 patients to a lower (<22.9) or higher (≥22.9) PAC group according to the median baseline PAC. The survival rate as calculated by the Kaplan-Meier method was 90.6% in the higher PAC group and 62.5% in the lower PAC group (p=0.003). In multivariate analysis, serum potassium and plasma renin activity were independent determinants of PAC. Cox proportional hazards analysis, with adjustment for other variables including diabetes, showed that lower PAC was independently predictive of death. The adjusted hazard ratio (95% confidence interval) of the lower PAC group was 2.905 (1.187–7.112, p=0.020). The significance of PAC became marginal by adjustment with albumin or potassium. These results indicate that higher PAC is common, but not associated with an increase in total and cardiovascular deaths among hypertensive patients undergoing chronic HD. The association between lower PAC and poor survival may be driven by volume retention and/or lower potassium.

Improved long-term survival rate of chronic dialysis patients with diabetes mellitus

AbstractBackground. The survival rate of diabetic dialysis patients has been poor. However, it is uncertain whether the survival rate of these patients has been improving. Methods. Using the Okinawa Dialysis Study (OKIDS) registry, in which the records of all chronic dialysis patients in Okinawa, Japan, are filed, we compared the prognosis of dialysis patients with diabetes mellitus (DM) and that of dialysis patients with chronic glomerulonephritis (CGN). Using Cox proportional hazard analysis, we examined the effect of the start year of dialysis on survival after adjusting for confounding variables such as age, sex, and predialysis comorbid conditions. Results. Between 1976 and 1998, a total of 1256 DM patients and 2101 CGN patients started dialysis. In the DM patients who started dialysis between 1976 and 1990, the survival rate was 80.4% at 12 months and 42.1% at 60 months, and among those who started dialysis between 1991 and 1998, the survival rate was 87.9% at 12 months and 55.8% at 60 months. In both disease groups, the relative risk of death was significantly lower in patients who started dialysis between 1991 and 1998 than in those who started dialysis between 1976 and 1990. The adjusted relative risk (95% confidence interval [CI]) was 0.65 (95% CI 0.54–0.77). The relative risk of death of DM to CGN was 2.23 (95% CI, 1.91–2.60) when comparing those treated between 1976 and 1990, and 2.00 (95% CI, 1.62–2.46) when comparing those treated between 1991 and 1998. Conclusions. While the prognosis of diabetic dialysis patients in both categories improved significantly with time, that of DM patients was still worse than that of CGN patients.

Cytokine production by peripheral blood lymphocytes and their LAK cell activity in patients on short- or long-term hemodialysis.

透析患者の末梢血リンパ球 (PBL) 機能について検討した. 対象は透析開始3年以内の透析導入および透析安定群, 10年以上の長期透析群, そして腎機能正常な対照群である. 検討項目は, PBLまたはLymphokine-activated killer (LAK) 細胞によるサイトカイン (IFN-γとTNF-α) 産生能と, 末梢血モノサイトのInterleukin-1 (IL-1) 産生能, そしてLAK細胞活性である. 透析開始3年以内の群では, 対照群に比して, LAK活性とIL-1産生能が有意に低下し, LAK細胞によるIFN-γ産生能も低下傾向を示した. Interleukin-2 (IL-2) 刺激PBLのIFN-γおよびTNF-αの産生量に関しては症例によりバラツキが大きく, 透析患者の両群いずれにおいても, 対照群との間に有意な差は見られなかった. 両サイトカインのともに産生量の低下した症例の割合が対照群に比べ3年以内の群で多かったが, 統計学的には有意な差は認められなかった. 一方TNFとIFNの産生量の多寡に関して相関が認められた. 従ってIL-2刺激により誘導されるLAK活性が低下している等の結果から, 透析3年以内の群において, IL-2に対するPBLの反応性の低下した症例の存在が示唆された.以上より, 我々の測定した免疫のパラメータに関するかぎり, 透析導入3年以内の患者においては免疫能の低下が認められるが, 10年以上の長期透析患者の免疫能は改善し, 健腎対象群のそれとに差異が認められなかった.