Factors associated with subgroups of fatigue in maintenance hemodialysis patients: a cross-sectional study.

OBJECTIVE: This study aimed to investigate affected factors for subgroups of fatigue and the degree of fatigue in maintenance hemodialysis (MHD) patients. METHODS: This study included 120 MHD patients. Questionnaires, pre- and post-dialysis clinical data, bioimpedance spectroscopy, and ultrasound assessment were involved. RESULTS: The prevalence of fatigue in participants was 83%, including 54% of patients with fatigue worsened by dialysis, 13% with fatigue lessened by dialysis, and 16% with undifferentiated fatigue. Based on multi-nominal logistic regression analysis, age was associated with worsened fatigue by dialysis (odds ratio (OR) = 1.06, 95% confidence interval (CI) 1.01-1.11, p = 0.019), lower post-dialysis phosphorus was associated with lessened fatigue by dialysis (OR = 0.03, 95% CI 0.001-0.981, p = 0.049), and there was an increasing trend of patients experiencing undifferentiated fatigue as the extracellular water / intracellular water (E/I) level increased (p for trend = 0.020). Based on multi-ordinal logistic regression analysis, age was also a significant predictor for more severe fatigue (OR = 1.042, 95% CI 1.008-1.059, p = 0.015). CONCLUSIONS: Different subgroups of fatigue in MHD patients have different affecting factors. Older patients were prone to worsened fatigue by dialysis, patients with lower post-dialysis phosphorus were prone to lessened fatigue by dialysis, and patients with higher E/I levels were prone to undifferentiated fatigue. Meanwhile, older patients are prone to suffer from more severe fatigue. However, more in-depth studies are needed to clarify the pathogenesis of fatigue in MHD patients.

A multiplex qPCR gene dosage assay for rapid genotyping and large-scale population screening for deletional α-thalassemia.

The predominant determinants of α-thalassemia are deletions in the human α-globin gene cluster. A rapid DNA-based assay is needed for mass screening in thalassemia-prevention programs. Herein, we established a novel quadruplex TaqMan qPCR gene dosage assay with two separate combination reactions. The assay directly determined the copy number of human α-globin genes based on relative quantitation of three target genes (HBA2, HBA1, and HBZ or HBPA1) versus a control gene (CREBBP). The assay showed good accuracy, with mean intra-assay and interassay variations of 3.31% ± 1.02% and 5.49% ± 0.32%, respectively. The assay was evaluated using 678 pretyped clinical DNA samples containing six α-thalassemia deletions in 13 genotypes and 186 normal samples previously screened by multiplex ligation-dependent probe amplification or gap PCR. As determined by the 2(-ΔΔCq) method, deleted gene dosage ratios were 0.46 to 0.60 in heterozygotes, 0.0 in homozygotes, and 0.97 to 1.07 in nondeleted samples. We found 99.3% concordance between the quantitative PCR and multiplex ligation-dependent probe amplification or gap-PCR results. Furthermore, routine screening for α-thalassemia deletions was performed on 3000 random samples in a blind analysis. Results for all 279 positives, which had different deletions, were fully coincident with results from standard methods. We also identified two novel deletions confirmed by multiplex ligation-dependent probe amplification. Assays using the novel method are simple and suitable for rapid genotyping and mass screening.