Associations of cardiovascular disease and blood pressure with cognition in hemodialysis patients: The Osaka Dialysis Complication Study

Association between Serum Zinc and All-Cause Mortality in Patients Undergoing Maintenance Hemodialysis: The Osaka Dialysis Complication Study (ODCS)

BACKGROUND/OBJECTIVES

Zinc is an essential microelement, and its deficiency is common in patients undergoing hemodialysis. However, the association between serum zinc and mortality in these patients remains unclear. The aim of this study was to explore the possible association between serum zinc levels and all-cause mortality in prevalent patients with kidney failure on maintenance hemodialysis.

METHODS

This was a prospective cohort study of maintenance hemodialysis patients followed up for 5 years. The key exposure was serum zinc level measured at baseline, and the outcome was all-cause mortality. Their association was analyzed using Cox proportional hazard models.

RESULTS

Among 1662 eligible patients selected for this analysis, 468 (28%) died. Lower serum zinc levels were associated with a higher risk for mortality, independent of the major demographic factors and factors including mineral and bone disorder and renal anemia. However, this association was no longer significant when adjusted for serum albumin. Because there was a close correlation between serum zinc and albumin levels, we performed further analyses in which participants were categorized into four groups by median serum zinc (68 µg/dL) and albumin (3.7 g/dL) levels. In the lower serum albumin groups, risk of death was significantly higher in those with lower zinc than those with higher zinc levels, whereas such a difference was not significant in the high serum albumin groups.

CONCLUSIONS

In patients undergoing maintenance hemodialysis with lower serum albumin levels, a lower serum zinc level was associated with a higher risk of mortality.

Needs, barriers and facilitators for a healthier lifestyle in haemodialysis patients: The GoodRENal project

BACKGROUND

Malnutrition, sedentary lifestyle, cognitive dysfunction and poor psychological well-being are often reported in patients on haemodialysis (HD).

AIMS

We aimed to explore needs, barriers and facilitators-as perceived by patients, their carers, and healthcare professionals (HCPs) for increasing the adherence to the diet, to physical activity and cognition and psychological well-being.

METHODS

This is an observational cross-sectional study following the STROBE statement. This study is part of an ERASMUS+ project, GoodRENal-aiming to develop digital tools as an educational approach to patients on HD. For that, the GoodRENal comprises HD centers located in four Belgium, Greece, Spain and Sweden. Exploratory questionnaires were developed regarding the perceived needs, barriers and facilitators regarding the diet, physical activity, cognition and psychological well-being from the perspective of patients, their carers and HCPs.

RESULTS

In total, 38 patients, 34 carers and 38 HCPs were included. Nutrition: For patients and carers, the main needs to adhere to the diet included learning more about nutrients and minerals. For patients, the main barrier was not being able to eat what they like. Physical activity: As needs it was reported information about type of appropriate physical activity, while fatigue was listed as the main barrier. For Cognitive and emotional state, it was perceived as positive for patients and carers perception but not for HCPs. The HCPs identified as needs working as a team, having access to specialised HCP and being able to talk to patients in private.

CONCLUSIONS

Patients and their carers listed as needs guidance regarding nutrition and physical activity but were positive with their cognitive and emotional state. The HCPs corroborated these needs and emphasised the importance of teamwork and expert support.

Lean-to-fat tissue ratio as a risk factor for cognitive impairment in patients undergoing maintenance hemodialysis

OBJECTIVE

The relationship between body mass index (BMI) and cognitive impairment (CI) remains controversial, and no research has been done to explore the effect of lean-to-fat (L/F) tissue ratio on the risk of CI in patients undergoing maintenance hemodialysis (MHD) so far. This study aimed to explore the effect of L/F tissue ratio on the risk of incident CI in patients undergoing MHD.

METHODS

In this observational cohort study, 3356 patients were recruited and followed up for a median of 2 years. Global cognitive function was measured using Mini-Mental State Examination score. Lean tissue mass (LTM) and fat tissue mass (FTM) were analyzed using body composition monitor based on bioimpedance spectroscopy (BCM-BIS), and L/F tissue ratio was calculated by LTM divided by FTM. Hazard ratios (HRs) for incident CI were determined by Cox regression.

RESULTS

The median age of the cohort was 55 years, and 68.7% patients were less educated. During the follow-up period, 1249 patients (37.2%) experienced incident CI. Patients with lower L/F tissue ratios had significantly higher risks of CI (HR 1.51, 95% confidence interval 1.24-1.84; p < 0.001) than those with higher L/F tissue ratios. The association between L/F tissue ratio and incident CI persisted in all subgroups stratified by sex, age, education status, especially in older and less educated participants. Both in all our patients and subgroups, BMI and CI occurrence were not independently relevant.

CONCLUSION

The L/F tissue ratio rather than BMI was an independent risk factor of incident cognitive impairment in patients undergoing MHD.

Low intracellular water and incident cognitive impairment in chronic hemodialysis patients

OBJECTIVE

To explore the effect of intracellular water (ICW) evaluated by the bioelectrical Impedance Spectroscopy (BIS) on the risk of incident cognitive impairment (CI) in chronic hemodialysis (HD) patients.

METHODS

Three thousand three hundred eighty-five patients were recruited and monitored prospectively for up to 3 years (the median follow-up time, 2 years) in this observational cohort study. Mini-Mental State Examination score (MMSE) was used to assess the global cognitive function. ICW was measured by body composition monitor based on BIS. Multiple Cox regression models, stratified analyses, and interactive analyses were conducted.

RESULTS

During the follow-up period, 1256 patients (37.1%) experienced incident CI. The incidence of CI was increased with decreasing quartiles of ICW (27.4%, 32.2%, 38.9%, and 50.1% for the fourth, third, second, and first quartiles, respectively). Decreased ICW was significantly associated with incident CI. The association remained statistically significant even after adjusting for age, sex, education, albumin, C-reactive protein, residual renal function and various medical histories. The hazard ratios were 1.38 (1.17-1.64) and 1.28 (1.08-1.52) for ICW quartile 1 and quartile 2, respectively (reference, quartile 4). The association stably existed across subgroups, and the residual renal function had an interactive role in the association between ICW and incident CI (p = 0.014).

CONCLUSION

Low baseline ICW was an independent risk factor for CI in chronic HD patients. Our finding highlights the necessity of using BIS to measure body composition when assessing the risk of CI in HD patients.

Association between Levocarnitine Treatment and the Change in Knee Extensor Strength in Patients Undergoing Hemodialysis: A Post-Hoc Analysis of the Osaka Dialysis Complication Study (ODCS)

Carnitine deficiency is prevalent in patients undergoing hemodialysis, and it could result in lowered muscle strength. So far, the effect of treatment with levocarnitine on lower limb muscle strength has not been well described. This observational study examined the association between treatment with levocarnitine with the change in knee extensor strength (KES) in hemodialysis patients. Eligible patients were selected from the participants enrolled in a prospective cohort study for whom muscle strength was measured annually. We identified 104 eligible patients for this analysis. During the one-year period between 2014 to 2015, 67 patients were treated with intravenous levocarnitine (1000 mg per shot, thrice weekly), whereas 37 patients were not. The change in KES was significantly higher (p = 0.01) in the carnitine group [0.02 (0.01–0.04) kgf/kg] as compared to the non-carnitine group [−0.02 (−0.04 to 0.01) kgf/kg]. Multivariable-adjusted regression analysis showed the positive association between the change in KES and the treatment with levocarnitine remained significant after adjustment for the baseline KES and other potential confounders. Thus, treatment with intravenous levocarnitine was independently and positively associated with the change in KES among hemodialysis patients. Further clinical trials are needed to provide more solid evidence.