Restless legs syndrome is associated with cardio/cerebrovascular events and mortality in end-stage renal disease.

BACKGROUND AND PURPOSE: Earlier studies suggested an association between idiopathic restless legs syndrome (RLS) and cardiovascular diseases. However, the risk of cardiovascular events in patients with secondary RLS due to end-stage renal disease (ESRD) is unclear. Our aim was to examine whether ESRD patients with RLS had an increased risk of cardio/cerebrovascular events and mortality. METHODS: In all, 1093 ESRD patients were recruited between 2009 and 2010. The diagnosis and severity of RLS were assessed in a face-to-face interview. The occurrence of cardio/cerebrovascular events and death were confirmed by medical record review. The association between RLS and the outcomes of interest was examined using an adjusted multivariate Cox regression model. RESULTS: After a mean follow-up period of 3.7 ± 0.8 years, ESRD patients with RLS had a significantly higher risk of developing cardiovascular events and strokes [adjusted hazard ratio (aHR) 2.82, 95% confidence interval (CI) 2.02-4.11, and aHR 2.41, 95% CI 1.55-3.75, respectively] compared with patients without RLS. Increasing RLS severity was associated with an increasing likelihood of cardiovascular events [mild RLS severity, aHR 1.71 (95% CI 1.02-2.87); moderate, 2.79 (1.64-4.66); severe, 2.85 (1.99-4.46)] and strokes [mild, 1.89 (0.87-4.16); moderate, 2.42 (1.50-3.90); severe, 2.64 (1.49-4.91)] in a dose-dependent manner. RLS also increased the risk of total mortality in patients with ESRD [aHR 1.53 (95% CI 1.07-2.18), P = 0.02]; this association attenuated slightly after stratification by individual RLS severity category [mild RLS severity, aHR 1.44 (95% CI 0.78-2.67); moderate, 1.49 (0.98-2.55); severe, 2.03 (0.93-4.45)]. CONCLUSIONS: ESRD patients with RLS demonstrated an increased likelihood of cardio/cerebrovascular events and mortality.

Association of candidate genetic variants with restless legs syndrome in end stage renal disease: a multicenter case-control study in Taiwan.

BACKGROUND AND PURPOSE: Recent genome-wide association studies have shown associations between multiple genetic variants and primary restless legs syndrome (RLS). Their roles in end stage renal disease (ESRD) related secondary RLS are not clear and studies in Asian populations are scarce. The association between candidate genetic variants and uremic RLS was investigated in a large cohort of Taiwanese dialysis patients. METHODS: Sixteen RLS-related genetic variants at six loci, including MEIS1, BTBD9, MAP2K5/SKOR1, PTPRD, TOX3/BC034767 and the intergenic region of chromosome 2p14, in a total of 993 ESRD patients (259 subjects with and 734 subjects without RLS) were genotyped using TaqMan genotyping assays. Multivariate logistic regression analysis was used to test for associations between the genotypes and RLS in ESRD. Power calculations were completed using the CATs Genetic Power Calculator with settings of a multiplicative genetic model. RESULTS: A modest association between the PTPRD variant rs4626664 and uremic RLS (odds ratio 1.52, 95% CI 1.03-2.23, P = 0.03) and a trend that TOX3/BC034767 variant rs3104767 may associate with the occurrence of RLS were observed in our dialysis population (odds ratio 1.74, 95% CI 0.97-3.11, P = 0.06). No associations between other genetic variants and risk and severity of RLS were observed in our ESRD cohort. CONCLUSIONS: The genetic variants of primary RLS candidate genes did not play a major role in our uremic RLS populations. The ethnic difference and heterogeneous etiologies underlying renal failure may partly explain the minor genetic contribution to uremic RLS in our populations. Further studies for other ethnicities will be of worth.

Restless legs syndrome in end-stage renal disease: a multicenter study in Taiwan.

BACKGROUND AND PURPOSE: Restless legs syndrome (RLS) is an underestimated movement disorder in patients with end-stage renal disease (ESRD). Several clinical and laboratory factors were inconsistently reported to associate with RLS. We aim to perform a large-scale multicenter study to investigate the possible associated risk factors of RLS in patients with ESRD in Taiwan, a country with the highest incidence of uremia in the world. METHODS: From October 2009 to October 2011, we constitutively recruited 1130 patients with ESRD from 17 hemodialysis centers. Demographic, laboratory data, presence and severity of RLS were collected. Odds ratios (ORs) were estimated by logistic regression models. RESULTS: We found the prevalence of RLS to be 25.3% in patients with ESRD. Having type 2 diabetes [OR = 3.61 (2.27-5.77), P < 0.01], low serum transferrin saturation [OR = 1.42 (1.01-2.03), P < 0.05] and duration of dialysis [OR = 1.09 (1.03-1.14), P < 0.01] were associated with RLS. In contrast, high serum hemoglobin level was inversely associated with RLS [OR = 0.61 (0.40-0.89), P < 0.05]. RLS has a significant impact on sleep quality in dialysis patients. Among patients with RLS, history of type 2 diabetes [OR = 4.04 (1.65-10.79), P < 0.05], low serum hemoglobin level [OR = 5.41 (2.43-13.12), P < 0.01] and duration of dialysis [OR = 1.01 (1.01-1.02), P < 0.01] were associated with increased severity of RLS. CONCLUSIONS: Our findings demonstrated that RLS is common in Taiwanese dialysis patients. Clinicians should have a high suspicion for the presence of RLS symptoms in patients with ESRD, especially those with type 2 diabetes, anemia, low serum iron status and long duration of dialysis.

Technetium-99m HIDA hepatic lobar distribution and retention ratios in detection of intrahepatic lithiasis.

Technetium-99m HIDA hepatic lobar distribution and retention ratios were developed to evaluate patients with intrahepatic lithiasis. The data of 57 cases were analyzed. Results reveal a highly significant difference in these ratios between the patients and normal individuals. They are simple, objective, and easily obtainable. Thus, the determination of these ratios may replace [99mTc]HIDA sequential scintiphotography, which is qualitative and time consuming, for screening intrahepatic lithiasis.