Effects of parathyroidectomy on plasma PTH fragments and heart rate variability in stage 5 chronic kidney disease patients

IntroductionCirculating intact parathyroid hormone (iPTH) levels include full-length (1-84) PTH and long C-PTH fragments, but primarily (7-84) PTH, which have been reported to have antagonistic effects on the bones and kidneys. However, their effects on the cardiovascular system remain unclear. In this study, the relationships between the plasma PTH fragments levels and heart rate variability (HRV) in stage 5 chronic kidney disease (CKD5) patients are explored. Furthermore, the effects of parathyroidectomy (PTX) on the above indices are investigated.MethodsIn this cross-sectional study, 164 healthy controls and 354 CKD5 patients, including 208 secondary hyperparathyroidism (SHPT) subgroup with PTX, were enrolled. Circulating (7-84) PTH levels were calculated by subtracting plasma (1-84) PTH levels from iPTH levels. The HRV parameters were measured using a 24-hour Holter.ResultsThe baseline levels of plasma iPTH, (1-84) PTH, and (7-84) PTH in the CKD5 patients were 930.40 (160.65, 1792.50) pg/mL, 448.60 (99.62, 850.45) pg/mL, and 468.20 (54.22, 922.55) pg/mL, respectively. In the CKD5 patients, plasma (1-84) PTH levels were independently correlated with the standard deviation of the normal-to-normal R-R intervals (SDNN) and the standard deviation of the five-minute average of the normal R-R intervals (SDANN). With a median follow up time of 6.50 months after PTX in the SHPT patients (n = 30), improved SDNN and SDANN markers were related with decreased (1-84) PTH levels. Furthermore, an improved SDNN was related with decreased (7-84) PTH levels.ConclusionsThe CKD5 patients’ baseline (1-84) PTH levels were correlated with the SDNN and SDANN. After PTX, an improved SDNN was related with decreased (1-84) PTH and (7-84) PTH levels, while improved SDANN was related with decreased (1-84) PTH levels. No antagonistic effects of (1-84) PTH and (7-84) PTH on HRV were found in the CKD5 patients.     

Serum endocan and circadian heart rate variability in non-dialysis stage 5 chronic kidney disease patients

Background

Chronic kidney disease (CKD) is very common now and is associated with high overall and cardiovascular mortality. Numerous studies have reported that elevated heart rate (HR) is a risk factor for cardiovascular mortality. We investigated the link between serum endocan and circadian heart rate variability in non-dialysis stage 5 CKD patients.

Methods

In a cross-sectional study, we enrolled 54 prevalent n non-dialysis stage 5 CKD patients (32 males, aged 48.2?±?14.92 years). HR was measured with an automatic system. Serum endocan level was analyzed by ELISA.

Results

Night/day HR ratio was independently predicted by serum endocan level (P?<?0.01) and hypertension history (P?<?0.05). Adjusted R² of the model was 0.222.

Conclusion

Increased serum endocan is significantly associated with circadian heart rate variability in non-dialysis stage 5 CKD patients. Further investigation is needed to explore the potential benefits of serum endocan lowering therapy in this patient group.

     

Day-by-day variability of home blood pressure in patients with chronic kidney disease

PURPOSE: We examined the characteristics of the day-by-day variability of home blood pressure (HBP) in patients with chronic kidney disease (CKD). METHODS: We obtained HBP recordings from 368 CKD patients (63+/-13 years, eGFR 34+/-23 mL/min/1.73 m2, males 253). The day-by-day variability of HBP was defined as the coefficient of variation (CV) values of BP measurements every morning after waking and every evening before sleeping on 7 consecutive days. In a portion of the patients, the CV values of HBP were collected every 6 months during a 2-year period and the association with a decline in GFR was examined. RESULTS: CV values of morning/evening systolic BP (SBP) were 5.4+/-2.4%, 6.1+/-2.9 % (p<0.01). The CV values of morning SBP in females or patients with diabetic nephropathy (DN) were significantly greater than those in males or patients without DN, respectively (females 5.9+/-2.3%, males 5.2+/-2.4%, p< 0.01, DN 6.1+/-2.8 %, non DN 5.2+/-2.2 %, p<0.05). Multivariate linear regression analysis showed that female gender, DN, the number of antihypertensive drugs, higher heart rate and higher CV values of heart rate were associated with higher CV values of the morning SBP. CV values of the morning SBP showed no significant change during the 2-year period (0; 5.4+/-2.6%, 1 year; 5.3+/-2.9%, 2 years 5.6+/-3.1%, n=200). There was no significant difference in the change in eGFR between a group with high CV values (greater than 5 %) and a group with low CV values (lower than 5 %) during the 2-year period. CONCLUSIONS: In CKD patients, the day-by-day variability of HBP tended to be greater in the evening, in female and DN patients. There was no significant association between the day-by-day variability of HBP and decline rate in eGFR. Further studies are needed to clarify the clinical significance of the day-by-day variability of HBP in CKD patients.     

慢性肾脏病患者动态血压参数及血压变异的特点分析

目的 分析慢性肾脏病（chronic kidney disease,CKD）患者动态血压参数与肾小球滤过率（GFR）及尿蛋白定量的相关性,并探讨血压变异性参数特点.方法 收集首次治疗的伴有高血压及蛋白尿的CKD患者70例.测量肾功能、24 h尿蛋白定量等生化检测结果,采用动态血压监测仪监测24 h血压并记录参数.根据GFR将患者分为CKD1~2期组和CKD3~5期组.根据24 h尿蛋白定量分为以下3组：Ⅰ组＜1.0 g,Ⅱ组1.0～3.5 g,Ⅲ组＞3.5 g.比较各组动态血压参数,并探讨监测结果与肾功能及蛋白尿的关系.结果 随着患者肾功能恶化,24 h收缩压、舒张压、脉压差、白昼收缩压、夜间收缩压等指标明显升高（P＜0.05）,且与GFR成负相关,白昼收缩压是GFR下降的独立危险因素.Ⅲ组的白昼舒张压（92.94±15.32）mm Hg明显高于Ⅰ组的（85.25±8.64）mm Hg（P＜0.05）.白昼舒张压与蛋白尿水平呈正相关（r=0.257,P=0.032）.所有患者舒张压变异性均明显高于收缩压变异性（P＜0.05）.结论 本研究样本中收缩压与肾功能恶化明显相关,白昼收缩压和舒张压分别与GFR下降及蛋白尿有关,舒张压变异性应受到更多重视.     

Association between visit-to-visit clinic blood pressure variability and home blood pressure variability in patients with chronic kidney disease

Abstract

Although both clinic blood pressure (BP) variability and home BP variability are associated with the risk of cardiovascular disease, the relationship between both BP variabilities remain unclear. We evaluated the association between visit-to-visit variability of clinic BP (VVV) and day-by-day home BP variability (HBPV) in patients with chronic kidney disease (CKD). We recruited 143 CKD patients in whom we performed HBP measurements every morning and evening over seven consecutive days. We obtained clinic BP data during 9.6?±?1.0 consecutive visits within 24 months. The associations between the variables of VVV and HPBV were examined. The CV values of clinic systolic BP (CSBP) was significantly correlated with the mean values of morning systolic BP (MSBP) and those of evening systolic BP (ESBP) (r?=?0.23, 0.20; p?=?0.007, 0.02, respectively). The CV values of CSBP was significantly correlated with the CV values of MSBP and those of ESBP (r?=?0.19, 0.31; p?=?0.02, <0.001, respectively). On the multivariate regression analysis, the CV values of CSBP was significantly correlated with the CV values of MSBP and those of ESBP [standardized regression coefficient (β)?=?0.19, 0.34; p?=?0.03, <0.001, respectively]. In conclusion, VVV showed a weak but significant association with HBPV, especially the CV values of ESBP in CKD patients. Further studies are necessary to clarify whether these different BPV elements will be alternative marker of BPV.     

Bone histomorphometry and biochemical markers of bone turnover in patients with chronic kidney disease Stages 3 - 5

AIMS: Precise identification of renal osteodystrophy requires bone histomorphometry. Several markers of bone turnover may be useful to predict classification and severity of renal osteodystrophy, but there are only limited data whether these markers correlate with bone histomorphometry. METHODS: In 36 patients with chronic kidney disease (CKD) Stage 3/4 and in 96 patients with CKD Stage 5 bone histomorphometry was performed and renal osteodystrophy was classified according to the standardized international nomenclature. Blood samples were taken at the time of bone biopsy, stored and analyzed at the end of the study. RESULTS: Osteitis fibrosa (OF) was the most frequent histomorphometric form, occurred in 47.2% in CKD Stages 3 - 4 and in 61.4% in CKD Stage 5. There was no difference in the frequency of adynamic renal bone disease (ARBD). The correlation coefficients between bone turnover markers and histomorphometric parameters were higher in CKD 5 patients with high bone turnover lesions. The predictive value for high versus low/normal bone turnover status was comparable for alkaline phosphatase (APH), bone alkaline phosphatase (BAP), pyridinoline (Pyd), desoxypyridinoline (Dpyd), tartrat-resistent acid phosphatase (TRAP Vb) and parathyroid hormone (PTH) in CKD Stage 5 patients, but was insufficient for APH and TRAP Vb in CKD Stage 3 - 4 patients. CONCLUSIONS: Besides parathyroid hormone, biochemical parameters of bone turnover provide a moderate discrimination and prediction of bone turnover status only in patients with CKD Stage 5. Due to a large variability, they are of limited use in predicting the histomorphometric type of renal osteodystrophy. Bone histology remains necessary for an exact classification of underlying pathology.     

慢性肾脏病中、晚期患者矿物质和骨代谢紊乱的知晓率、治疗率和控制率

目的 调查我院慢性肾脏病（CKD）中、晚期非透析和透析患者矿物质和骨代谢紊乱的知晓率、治疗率和控制率。 方法 选取503例CKD 3期以上的非透析和透析患者,通过问卷的形式,结合实验室检查了解患者对矿物质和骨代谢紊乱的知晓率、治疗率和控制率。 结果 CKD中、晚期患者矿物质和骨代谢紊乱知识知晓率以血液透析患者最高,腹膜透析患者其次,非透析患者最低,差异有统计学意义（P < 0.01）。知识调查总得分显示,腹膜透析[11（9,12）]和血液透析[13（11,15）]患者显著高于非透析患者[6（5,8）]（P < 0.01）。相关知识的了解程度与年龄（r = -0.11,P < 0.05）呈负相关;与文化程度（r = 0.226,P < 0.01）、肾脏病病程（r = 0.597,P < 0.01）和透析龄（r = 0.366,P < 0.01）呈正相关。医护人员宣教是CKD中、晚期患者获取知识的主要渠道,在非透析、腹膜透析和血液透析患者中分别占94.0%、79.5%和69.4%。腹膜透析（88.6%）和血液透析（96.9%）患者的矿物质和骨代谢紊乱治疗率均显著高于非透析患者（58.2%）（均P < 0.01）。在控制率方面,以K/DOQI指南为标准,非透析患者血钙、血磷、钙磷乘积和甲状旁腺素（PTH）等的达标率明显优于透析患者;在各项指标的达标数量上也显著优于透析患者（均P < 0.01）。以KDIGO指南为标准,非透析（46.7%）和腹膜透析（36.9%）患者的血磷达标率均显著高于血液透析患者（23.6%）（均P < 0.01）。 结论 CKD中、晚期非透析患者矿物质和骨代谢紊乱的知晓率和治疗率较低,控制率较高;而透析患者的知晓率和治疗率较高,但控制率较低。     

Use of alternative medicine by patients with stage 5 chronic kidney disease

The use of complementary and alternative medicine (CAM) in the United States is growing at a remarkable speed. Herbal products and dietary supplements are CAM therapies that have grown faster than any other CAM treatments. Little information is available about herbs and dietary supplement use in the stage 5 chronic kidney disease population. These products contain a myriad of pharmacologically active compounds that, when used by people with kidney disease, may be hazardous. Members of the renal dietitian listserv were queried about herbs and dietary supplements reportedly used by dialysis patients. Up-to-date information on the use, safety, efficacy, adverse effects, and recommended dosages in the nondialysis population are presented for 24 products. In the dialysis population, Noni juice should be avoided because of its high potassium content. In addition, bulk-forming laxatives such as flaxseed should be used with caution because of the need for increased fluid intake. Dialysis practitioners should include specific questions about herbs and dietary supplement use in medical and nutrition histories, and they should increase their knowledge about these products to advise patients appropriately. A list of reliable sources of information for the health care provider on herbs and dietary supplements is also presented.     

慢性肾脏病5期患者碳酸氢盐水平与矿物质和骨代谢异常的相关性分析

目的分析未行透析治疗的慢性肾脏病5期(chronic kidney disease 5 period,CKD5)患者血清碳酸氢盐与骨代谢指标的关系,探索终末期肾脏病(end stage renal disease,ESRD)患者代谢性酸中毒与慢性肾脏病的矿物质和骨代谢异常(mineral and bone metabolic abnormalities in chronic kidney disease,CKD-MBD)发生的关系及可能机制。方法收集2014年8月至2016年10月就诊未行透析治疗的CKD5期患者252例,根据血清标准碳酸氢盐(standard bicarbonate,SB)水平对患者进行分组,SB22 mmol/L定义为伴有酸中毒组(217例),SB22 mmol/L定义为不伴有酸中毒组(35例)。收集SB、血肌酐(serum creatinine,Scr)、尿素氮(blood urea nitrogen,BUN)、血白蛋白(blood albumin,Alb)、血钙(Ca)、血磷(P)、甲状旁腺素(parathyroid hormone,PTH)、血β2-微球蛋白(β2-MG)、Ⅰ型胶原羧基端肽β特殊序列(β-CTX)及总Ⅰ型胶原氨基端前肽(TPINP)等指标,计算钙磷乘积(Ca×P)。对两组患者各项参数进行对比分析,并分别与SB作相关性分析。结果伴有酸中毒组BUN、PTH、P、Ca×P、β2-MG、β-CTX及TPINP等指标均较不伴酸中毒组高,伴有酸中毒组血Ca较不伴酸中毒组低,而两组间Scr及Alb差异无统计学意义。相关性分析显示SB与血Ca呈正相关,相关系数为0. 255;与PTH、Ca×P、β2-MG、β-CTX及TPINP呈负相关,相关系数分别为-0. 869、-0. 656、-0. 775、-0. 615和-0. 720;与血P无明显相关。结论代谢性酸中毒参与了未行透析治疗CKD5期患者CKD-MBD的发生,其可能机制是代谢性酸中毒诱导了成骨细胞与破骨细胞功能失衡。     

Determination of bone architecture and strength in men and women with stage 5 chronic kidney disease

Fractures are common in men and women with dialysis-dependent chronic kidney disease (stage 5D CKD) and are associated with substantial morbidity and mortality. The clinical utility of dual energy X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT), noninvasive measures of bone mass and architecture that reflect fracture risk in healthy men and women, is uncertain in patients with stage 5D CKD. This review will outline the epidemiology and etiology of fractures and will summarize the published data that describe the association between fractures, bone mass, and bone strength in stage 5D CKD. Fracture risk assessment in stage 5D CKD is complicated as the etiology of fractures is multifactorial and includes impairments in bone quantity and quality. Cross-sectional data suggest that bone density by DXA is lower among stage 5D CKD patients with fractures compared with those without, and that this may be particularly true at cortical sites. However, DXA does not capture bone microarchitecture and cannot differentiate between cortical and trabecular bone. Some, but not all studies, that measure cortical and trabecular bone by pQCT in stage 5D CKD, demonstrate a preferential decrease in cortical bone; however, these studies are limited by small sample sizes and cross-sectional study design. No studies have reported on longitudinal relationships between bone architecture, strength, and incident fractures in patients with stage 5D CKD. Further research is needed to identify noninvasive measures of bone strength that can be used for fracture risk assessment in stage 5D CKD.     

Vitamin D levels, bone turnover and bone mineral density show seasonal variation in patients with chronic kidney disease stage 5

AIM: Many patients with chronic kidney disease (CKD) have reduced levels of 25-hydroxyvitamin D (25(OH)D). Although renal conversion of 25(OH)D to calcitriol is reduced or absent in CKD stage 5 (GFR < 15 mL/min per 1.73 m(2) or on dialysis), 25(OH)D may have direct skeletal and non-skeletal paracrine actions. The aim of this study was to assess seasonal variation in levels of 25(OH)D, bone turnover markers and bone mineral density, which would support a direct physiological role for 25(OH)D. METHODS: Vitamin D levels, bone turnover markers and bone mineral density were measured and assessed for seasonal variation in 257 patients about to undergo kidney or kidney pancreas transplantation. RESULTS: The mean age was 43 +/- 11 years; 62% were on haemodialysis, 24% on peritoneal dialysis and 34% had type 1 diabetes. Serum 25(OH)D was less than 50 nmol/L in 39% and lower levels were associated with female sex, diabetes and peritoneal dialysis (P < 0.0001 for each). Levels of 25(OH)D varied by season (P = 0.018; anova) peaking in autumn with a nadir in spring and calcitriol levels followed a similar seasonal trend. Bone mineral denisty Z-scores differed between summer and winter at the lumbar spine (P = 0.009) with a similar trend at the hip. Osteocalcin levels also showed seasonal periodicity (P = 0.0142) and together with alkaline phosphatase were higher in summer than winter. CONCLUSION: In summary, these data suggest direct effects of 25(OH)D on bone parameters in CKD stage 5 and support the need for prospective studies to establish the effect of treatments that increase 25(OH)D levels in all stages of CKD.     

Factors associated with calcium requirements after parathyroidectomy in chronic kidney disease patients

Background

Renal hyperparathyroidism is a common complication of chronic kidney disease (CKD). Parathyroidectomy (PTX) for these patients continues to be a valuable option in the era of calcimimetics. Postoperative hypocalcemia is common after surgery. The aim of this study was to identify clinical factors to define postoperative calcium requirements.

Methods

From February 2013 to May 2017, 68 patients with chronic kidney disease 5 (CKD5) who underwent PTX were reviewed. We collected clinical and laboratory data preoperatively and calculated the total calcium requirement in a week after surgery. Univariate and multiple analyses were performed to study whether these clinical and laboratory factors were associated with calcium requirement.

Results

Univariate analysis showed that preoperative alkaline phosphatase (ALP), calcium (Ca), parathyroid hormone and hemoglobin were independently associated with calcium requirement. Multivariate model showed that the preoperative ALP was the only independent factor that could predict the requirement of calcium.

Conclusions

In the context of a high dCa (1.75 mmol/l) and a stable dose of calcitriol, preoperative ALP levels were significantly associated with calcium requirement in patients with CKD5 undergoing PTX.

     

Effects of parathyroidectomy on plasma iPTH, (1-84)PTH and (7-84)PTH levels in patients with stage 5 chronic kidney disease

Objective Currently, parathyroid hormone (PTH) is mainly measured by the second generation intact PTH (iPTH) assay which detects both full-length (1-84)PTH and (7-84)PTH fragments. The third generation whole PTH (wPTH) assay however has turned out to be specific for (1-84)PTH. The aim of this study is to investigate the features of plasma iPTH, (1-84)PTH, (7-84)PTH levels in patients with stage 5 chronic kidney disease (CKD), and evaluate the effects of parathyroidectomy (PTX) on above markers in severe secondary hyperparathyroidism (SHPT) patients. Methods A cross-sectional study including 90 controls and 233 stage 5 CKD patients, and a prospective follow-up study in 31 severe SHPT patients were conducted. Plasma iPTH and (1-84)PTH levels were measured by the second and third generation assay, respectively. Circulating (7-84)PTH level was calculated by subtracting the (1-84)PTH value from the iPTH value. Results Plasma levels of iPTH, (1-84)PTH, (7-84)PTH were higher (P＜0.01), and (1-84)PTH/iPTH was lower (P＜0.01) in stage 5 CKD patients than in controls. For severe SHPT patients with PTX (n=74), plasma iPTH, (1-84)PTH and (7-84)PTH concentrations were significantly increased compared to non-PTX group (n=159) (P＜0.01), and the increase of (7-84)PTH level was more striking than (1-84)PTH. Meanwhile, the value of (1-84)PTH/iPTH was decreased (P＜0.01). Plasma iPTH level was strongly correlated with (1-84)PTH level (r=0.980, P＜0.01) in stage 5 CKD patients. Also, both iPTH and (1-84)PTH levels were positively correlated with serum alkaline phosphatase, dialysis vintage and serum phosphorus (P＜0.01). After PTX (median interval of follow-up: 7.1 months), plasma iPTH, (1-84)PTH, (7-84)PTH concentrations were decreased (by 92.9%, 89.7%, 95.8%, P＜0.01, respectively) greatly and (1-84)PTH/iPTH was increased (P＜0.01). Conclusions In stage 5 CKD patients, plasma iPTH, (1-84)PTH, (7-84)PTH levels are greatly increased while (1-84)PTH/iPTH is decreased, and PTX can significantly improve abnormality of above markers in severe SHPT patients. The second generation PTH assay overestimates the severity of SHPT, and the accurate measurement of (1-84)PTH by the third assays is more conducive to diagnosis and treatment of CKD and SHPT patients.     

Adynamic bone in patients with chronic kidney disease

Adynamic bone in patients with chronic kidney disease (CKD) is a clinical concern because of its potential increased risk for fracture and cardiovascular disease (CVD). Prevalence rates for adynamic bone are reportedly increased, although the variance for its prevalence and incidence is large. Differences in its prevalence are largely attributed to classification and population differences, the latter of which constitutes divergent groups of elderly patients having diabetes and other comorbidities that are prone to low bone formation. Most patients have vitamin D deficiency and the active form, 1,25-dihydroxyvitamin D, invariably decreases to very low levels during CKD progression. Fortunately, therapy with vitamin D receptor activators (VDRAs) appears to be useful in preventing bone loss, in part, by its effect to stimulate bone formation and in decreasing CVD morbidity, and should be considered as essential therapy regardless of bone turnover status. Future studies will depend on assessing cardiovascular outcomes to determine whether the risk/reward profile for complications related to VDRA and CKD is tolerable.     

慢性肾脏疾病患者血压变异性与血脂异常的关系

目的探讨慢性肾脏疾病（chronickidneydisease,CKD）1～4期患者血脂代谢异常与血压变异性的相关性。方法入选142例CKD1-4期的患者,将不伴有高脂血症的患者47例设为A组,其中男28例,女19例;伴有高脂血症的患者95例设为B组,其中男56例,女39例。记录2组饮酒史、吸烟史、病程、年龄、性别、身高、体质量、诊所血压,并计算体质量指数。测量空腹时血清总胆固醇（totalcholesterol,TC）、三酰甘油（triglyceride）、低密度脂蛋白胆固醇（10wdensitylipopro—teincholesterol,U）L厂C）、高密度脂蛋白胆固醇（high-densitylipoproteincholesterol,HDL-C）、肌酐、尿酸,对入选的患者进行24h动态血压监测（ambulatorybloodpressure,ABPM）。收集血压参数,将2组血压标准差及变异系数进行对比分析,并将B组的血压变异系数与血脂值进行相关性检验与回归分析,了解血脂异常与CKD患者血压变异性的相关性。结果与A组比较,B组的24h收缩压标准差变异系数和白昼收缩压标准差变异系数增大,差异有统计学意义（P〈0．05）,B组24h收缩压标准差变异系数与TC值呈正相关（r=0．21,P=0．03）,但未能建立回归方程;白昼收缩压标准差变异系数与TC值呈正相关（r=0．19,P=0．04）,但未能建立回归方程;夜间收缩压标准差变异系数与TC值呈正相关（r=0．22,P=0．02）,但未能建立回归方程。结论CKD合并血脂异常较不伴有血脂异常者血压变异性增大,且收缩压血压变异性与TC值呈正相关,提示CKD患者血压变异性与血脂异常之间存在密切的关系,二者联合干预治疗对于减少CKD患者心血管疾病的发生、改善CKD发展和预后具有重要的意义。     

Prognostic value of heart rate variability in patients with end-stage renal disease on chronic haemodialysis.

BACKGROUND: Although decreased heart rate variability (HRV) is an independent predictor of death in various populations, its prognostic value in patients with end-stage renal disease on chronic haemodialysis is unknown. METHODS: We prospectively studied 120 chronic haemodialysis patients (age 61+/-11 years; males 51%; diabetics 38%; duration of haemodialysis therapy 50+/-114 months) who underwent 24 h electrocardiography at baseline for analysis of time- and frequency-domain HRV. RESULTS: All HRV measures in the patients were significantly reduced compared with those obtained from 62 age-matched healthy subjects. During a follow-up period of 26+/-10 months, 21 patients died (17.5%); 10 from cardiac causes and 11 from non-cardiac causes (seven fatal strokes and four other causes). A Cox proportional hazards model revealed that, of the HRV measures, decreases in the triangular index (TI), very-low-frequency (0.0033-0.04 Hz) power, ultra-low-frequency (<0.0033 Hz) power (ULF) and the ratio of low-frequency (0.04-0.15 Hz) power to high-frequency (0.15-0.4 Hz) power had significant predictive value for cardiac death. None of the HRV measures, however, had predictive value for non-cardiac death, including stroke death. Even after adjustment for other univariate predictors including age, diabetes, serum albumin and coronary artery disease, the predictive value of decreased TI and ULF remained significant-adjusted relative risk (95% confidence interval) per 1 SD decrement of TI and ULF, 3.28 (1.08-9.95) and 1.92 (1.01-3.67), respectively. CONCLUSIONS: Decreases in some HRV measures, particularly those reflecting long-term variability, are independent predictors of cardiac death in chronic haemodialysis patients.