Low parathyroid hormone levels after parathyroidectomy reduce cardiovascular mortality in chronic hemodialysis patients.

BACKGROUND: The aim of the study is to elucidate whether parathyroid hormone (PTH) levels after parathyroidectomy affect the prognosis of patients with secondary hyperparathyroidism. SUBJECTS AND METHODS: Two hundred and ninety-five patients, who underwent PTx without autotransplantation from July 1998 to December 2011, were divided into the low (n = 148) and high (n = 147) PTH groups, using the median value of each mean value of intact PTH after surgery (16.6 pg/mL). After observation for 5.00 years, we evaluated demographic factors, influences of postoperative mineral metabolism, magnitude of uremia, and vitamin D receptor activators on their prognosis, with the multivariate Cox proportional hazard model. RESULTS: While overall survival rates in the high and low PTH groups were 54.9 and 74.2 %, respectively (P = 0.1500), cardiovascular survival rates were 71.6 and 94.4 %, respectively (P = 0.0256). The hazard ratio for cardiovascular mortality in the high PTH group (≥16.6 pg/mL) was 3.132 (P = 0.0470), and those in groups with the median age more than 59 years and with cardiovascular disease were 2.654 (P = 0.0589) and 3.377 (P = 0.0317), respectively. The intact PTH level 6 days after surgery and the mean postoperative intact PTH value showed a strong correlation (Spearman ρ = 0.9007, P < 0.0001, y = 0.4725x + 30.395, R 2 = 0.51798). CONCLUSION: The present study suggests that maintaining low PTH levels after parathyroidectomy reduces cardiovascular mortality and improves the prognosis. Total parathyroidectomy (more than 4 glands) without autotransplantation seems to be one of the treatment options for managing severe secondary hyperparathyroidism.

Effects of intravenous l-carnitine on myocardial fatty acid imaging in hemodialysis patients: responders or non-responders to l-carnitine.

We investigated whether chronic intravenous administration of l-carnitine could improve myocardial fatty acid imaging in patients on maintenance hemodialysis. We enrolled 72 hemodialysis patients who had impaired myocardial fatty acid imaging and left ventricular dysfunction not based on coronary lesion. l-Carnitine (1,000 mg) was intravenously administered after dialysis for 1 year to 36 participants (Carnitine group), while not in the other 36 participants (Control group). Single-photon emission computed tomography (SPECT) using an iodinated fatty acid analogue, BMIPP, was performed. Uptake on SPECT images was graded in 17 segments on a five-point scale (0, normal; 4, absent) and assessed as BMIPP summed scores. During follow-up, 19 participants were discontinued from the study, and 53 participants (65 ± 12 years: 27 carnitine, 26 control) were analyzed. The mean BMIPP summed scores 1 year after carnitine administration did not differ from that before in the carnitine group, nor from that in the control group. However, improved SPECT (Changes in BMIPP summed scores <-20%) was found in 7 (25.9%) participants in the carnitine, whereas in 2 (7.7%) in the control group. Multivariate logistic analysis showed the improved SPECT was inversely associated with baseline serum albumin levels (1 g/L: odds ratio, 0.669); the cut-off was 35 g/L. Chronic intravenous l-carnitine might improve myocardial fatty acid imaging in a selected group of hemodialysis patients with hypoalbuminemia.

Improvement of myocardial fatty acid metabolism by oral nicorandil in hemodialysis patients without coronary artery disease.

BACKGROUND: We investigated the potential of oral nicorandil to improve myocardial fatty acid metabolism assessed by single-photon emission computed tomography (SPECT) using (123)I-ß-methyliodophenyl pentadecanoic acid (BMIPP) in hemodialysis patients without obstructive coronary artery disease (CAD). METHODS: This study was based on a cohort study of 155 hemodialysis patients with angiographic absence of obstructive CAD, with analysis performed in 100 propensity-matched patients (54 men and 46 women, 64 ± 10 years); 50 with oral administration of nicorandil (15 mg/d, nicorandil group) and 50 without (control). BMIPP SPECT was performed every year after angiography. Uptake on SPECT was graded in 17 segments on a five-point scale (0 normal, 4 absent) and assessed as BMIPP summed scores (SS). RESULTS: Over a mean follow-up period of 5.3 ± 1.9 years, we observed 25 cardiac deaths among 100 propensity-matched patients. Myocardial uptake of BMIPP in SPECT improved in the nicorandil group compared with the control group from 2 years of administration. In Kaplan-Meier survival analyses, free survival rate from cardiac death was higher in patients with a BMIPP SS improvement rate of ≥20% compared to those with ≥0% <20% or with <0% BMIPP SS improvement rate. At multiple logistic analysis, a ≥20% BMIPP SS improvement rate was positively associated with serum albumin concentration and oral nicorandil. CONCLUSIONS: Long-term oral nicorandil may inhibit cardiac death by improving myocardial fatty acid metabolism in hemodialysis patients without obstructive CAD.

Clinical potential of oral nicorandil to improve myocardial fatty acid metabolism after percutaneous coronary intervention in hemodialysis patients.

BACKGROUND/AIMS: The assessment of myocardial fatty acid metabolism impairment by single-photon emission computed tomography (SPECT) using (123)I-ß-methyliodophenyl-pentadecanoic acid (BMIPP) might predict the risk of cardiac death in hemodialysis patients. We investigated the potential of oral nicorandil to improve myocardial fatty acid metabolism after percutaneous coronary intervention (PCI) in this population. METHODS: We evaluated 128 hemodialysis patients who had obtained coronary revascularization by PCI (90 men and 38 women, 66 ± 9 years). Participants for the analysis were randomly assigned to either the nicorandil (n = 63) or control group (n = 65). BMIPP SPECT was performed every year after coronary revascularization by PCI. Uptake on SPECT was graded in 17 segments on a 5-point scale (0, normal; 4, absent) and assessed as BMIPP summed scores (SS). RESULTS: The incidence of cardiac death was lower (p = 0.004) in the nicorandil group (7/63, 11.1%) than in the control group (21/65, 32.3%) during a mean follow-up of 2.7 ± 1.4 years. BMIPP SS reduction rates improved in the nicorandil group compared with the control group from 3 years of administration. In Kaplan-Meier analyses, free survival rate of cardiac death was higher in patients with a ≥20% BMIPP SS reduction rate as compared with those with a <20% BMIPP SS reduction rate (p = 0.0001). In multiple logistic analysis, oral administration of nicorandil was associated with ≥20% reduction rates of BMIPP SS (odds ratio 2.823, p = 0.011). CONCLUSION: Long-term oral administration of nicorandil may improve impaired myocardial fatty acid metabolism after coronary revascularization by PCI in hemodialysis patients.

Total parathyroidectomy improves survival of hemodialysis patients with secondary hyperparathyroidism.

BACKGROUND AND AIMS: To compare the prognosis of chronic hemodialysis patients with or without parathyroidectomy. METHODS: Among 158 chronic hemodialysis patients who underwent total parathyroidectomy between July 1998 and April 2009, 88 patients were matched with 88 controls for sex, age, underlying disease and prior dialysis history. Then a retrospective evaluation of their prognosis was performed over a median observation period of 4.41 years. RESULTS: The overall survival rate was 90.4% in the parathyroidectomy group and 67.4% in the control group. The cardiovascular death-free survival rate was 94.6% in the parathyroidectomy group and 76.3% in the control group. During observation, intact parathyroid hormone was measured every 6 months, and its average serum level was 37 ± 92 ng/L in the total parathyroidectomy group versus 274 ± 233 ng/L in the control group (p=0.0001). The total parathyroidectomy group had a significantly lower corrected calcium level and higher serum albumin level. Multivariate analysis revealed that parathyroidectomy, atrial fibrillation and serum albumin were significant factors for both total and cardiovascular mortality. CONCLUSION: Total parathyroidectomy was associated with better survival, probably due to decreased cardiovascular mortality.

Oral nicorandil for prevention of cardiac death in hemodialysis patients without obstructive coronary artery disease: a propensity-matched patient analysis.

BACKGROUND/AIMS: We examined the potential of oral administration of nicorandil for protecting against cardiac death in hemodialysis patients without obstructive coronary artery disease. METHODS: This study was based on a cohort study of 155 hemodialysis patients with angiographic absence of obstructive coronary lesions, with analysis performed in 100 propensity-matched patients (54 men and 46 women, 64 ± 10 years), including 50 who received oral administration of nicorandil (15 mg/day, nicorandil group) and 50 who did not (control). The efficacy of nicorandil in preventing cardiac death was investigated. RESULTS: Over a mean follow-up period of 5.3 ± 1.9 years, we observed 25 cardiac deaths among 100 propensity-matched patients, including 6 due to acute myocardial infarction, 11 due to heart failure, and 8 due to sudden cardiac death. The incidence of cardiac death was lower (p < 0.001) in the nicorandil group (4/50, 8%) than in the control (21/50, 42%). On multivariate Cox hazard analysis, cardiac death was inversely associated with oral nicorandil (hazard ratio, 0.123; p = 0.0002). On Kaplan-Meier analysis, cardiac death-free survival rates at 5 years were higher in the nicorandil group than in the control group (91.4 vs. 66.4%). CONCLUSION: Oral nicorandil may inhibit cardiac death of hemodialysis patients without obstructive coronary artery disease.

Clinical potential of nicorandil to inhibit major cardiac events in hemodialysis patients with suspected myocardial ischemia.

BACKGROUND/AIMS: We examined whether nicorandil, which is a hybrid of an adenosine triphosphate-sensitive potassium channel opener and a nitrate, could inhibit major adverse cardiac events (MACE) in maintenance hemodialysis patients with suspected myocardial ischemia. METHODS: We enrolled 148 asymptomatic patients on maintenance hemodialysis, who had exhibited potential myocardial ischemia as assessed by myocardial fatty acid imaging. The end-point was MACE including cardiac death and non-fatal acute myocardial infarction. A propensity-matched analysis was performed. RESULTS: Over a mean duration of follow-up of 2.8 +/- 1.6 years in the 82 propensity-matched patients (41 in the nicorandil group and 41 in the non-nicorandil group), we observed 17 cardiac deaths and 12 cases of nonfatal myocardial infarction. The incidence of MACE was lower (p = 0.0365) in the nicorandil group (10/41, 24.4%) than in the non-nicorandil group (19/41, 46.3%). On stepwise Cox hazard analysis, MACE was significantly inhibited by administration of nicorandil (hazard risk, 0.387; 95% CI 0.178-0.842; p = 0.0168). Kaplan-Meier survival estimates revealed that MACE-free survival rates at 3 years were 80.5 and 58.5% in patients with and without nicorandil, respectively. CONCLUSIONS: Oral administration of nicorandil may offer new potential for the inhibition of MACE in hemodialysis patients.

Familial central diabetes insipidus detected by nocturnal enuresis.

A 10-year-old male referred to our clinic with the chief complaint of nocturnal enuresis also complained of daytime polyuria, frequency, and polydipsia. The clinical diagnosis was central diabetes insipidus. Since the patient's father had complained of similar symptoms, the arginine vasopressin-neurophysin II gene was examined. This revealed a single base substitution in one of two alleles in the patient, his father, and his grandfather (a C to T transition at nucleotide position 280 at codon 19 in the first exon). In conclusion, a history of polyuria or polydipsia should be carefully noted and the urinary volume and urine gravity or osmolarity examined in cases of nocturnal enuresis.