Are there any seasonal changes of cognitive impairment, depression, sleep disorders and quality of life in hemodialysis patients?

Seasonality of cognitive function in the general population: the Rotterdam Study

Seasonal variation in cognitive function and underlying cerebral hemodynamics in humans has been suggested, but not consistently shown in previous studies. We assessed cognitive function in 10,276 participants from the population-based Rotterdam Study, aged 45 years and older without dementia, at baseline and at subsequent visits between 1999 and 2016. Seasonality of five cognitive test scores and of a summary measure of global cognition were determined, as well as of brain perfusion. Using linkage with medical records, we also examined whether a seasonal variation was present in clinical diagnoses of dementia. We found a seasonal variation of global cognition (0.05 standard deviations [95% confidence interval: 0.02–0.08]), the Stroop reading task, the Purdue Pegboard test, and of the delayed world learning test, with the best performance in summer months. In line with these findings, there were fewer dementia diagnoses of dementia in spring and summer than in winter and fall. We found no seasonal variation in brain perfusion. These findings support seasonality of cognition, albeit not explained by brain perfusion.

Seasonal variations in nutritional status and oxidative stress in patients on hemodialysis: Are they related?

OBJECTIVE

Seasonal variations in body composition and parameters that reflect nutritional status are well established in patients on hemodialysis (HD). However, to our knowledge, no study has assessed the changes in oxidative stress (OS). The aims of this study were to assess seasonal variations in OS, body composition, and other nutritional parameters.

METHODS

Seasonal variations in fat tissue mass (FTM), fat tissue index (FTI), adipose tissue mass (ATM), lean tissue mass (LTM), lean tissue index (LTI), body cell mass (BCM), overhydration (OH) volume, and OS (blood levels of derivatives of reactive oxygen metabolites [d-ROMs], thiobarbituric reactive substances, plasma protein reduced thiol content [THIOLS], and ferric reducing ability of plasma) were assessed in 45 patients on HD, 70 y of age (60.5-76.5 y).

RESULTS

FTM (P < 0.001), FTI (P < 0.001), and ATM (P < 0.001) significantly increased, whereas LTI (P < 0.001), LTM (P < 0.001), BCM (P < 0.001), and OH volume (P = 0.004) significantly decreased over the season. Additionally, significant seasonal variations in the levels of d-ROMs (P = 0.02) and THIOLS (P = 0.02) were found. Levels of d-ROMs were found to be a significant predictor of LTM and BCM (β = -0.57; 95% confidence interval [CI], -1.08 to -0.06; P = 0.03; β = -0.04; 95% CI, -0.075 to -0.006; P = 0.02). Furthermore, hip circumference was found to be the most significant predictor of the level of d-ROMs (β = 2.66; 95% CI; 0.28-5.04; P = 0.03) and waist-to-height ratio (β = 251; 95% CI, 16.6-477.2; P = 0.03) and serum prealbumin levels of THIOLS (β = 263; 95% CI, 6.8-521.1; P = 0.04).

CONCLUSION

These results suggest seasonal variations in OS in patients on HD and a possible interaction between OS and nutritional status in these patients.

Quality of life, depression, and anxiety of patients undergoing hemodialysis: Significant role of acceptance of the illness

OBJECTIVE

Routine dialysis is stressful. It has the possibility of leading to depression and anxiety and also reducing patients' quality of life. Despite these significant consequences, these comorbidities have been rarely studied among Indonesian patients. This study aims to examine the rate of depression, anxiety, and the role of acceptance of their illness on patients' quality of life.

METHOD

A total of 213 patients undergoing hemodialysis in three general hospitals in Aceh, Indonesia, were included in the study. The presence of depression, anxiety, and the quality of life of each patient was assessed using the hospital anxiety and depression scale and WHO quality of life-BREF questionnaires.

RESULTS

The prevalence of depression and anxiety was 46% and 30.5%, respectively. Depression was only associated with the presence of anxiety and the duration of hemodialysis. Anxiety was negatively associated with quality of life but positively associated with depression and the prescription of an anxiolytic. Overall quality of life was associated with age, body mass index, the presence of anxiety, and acceptance of the illness. Acceptance of the illness was also independently associated with almost every domain of patients' quality of life.

CONCLUSIONS

The rates of depression and anxiety among patients undergoing hemodialysis in the current study setting are relatively similar to the rates in other settings. Patients' acceptance of their illnesses is significantly associated with the occurrence of anxiety and quality of life. Therefore, health practitioners should help patients accept their illnesses and the administration of regular hemodialysis.

Diurnal and seasonal molecular rhythms in the human brain and their relation to Alzheimer disease

Diurnal and seasonal rhythms influence many aspects of human physiology including brain function. Moreover, altered diurnal and seasonal behavioral and physiological rhythms have been linked to Alzheimer's disease and related dementias (ADRD). Understanding the molecular basis for these links may lead to identification of novel targets to mitigate the negative impact of normal and abnormal diurnal and seasonal rhythms on ADRD or to alleviate the adverse consequences of ADRD on normal diurnal and seasonal rhythms. Diurnally and seasonally rhythmic gene expression and epigenetic modification in the human neocortex may be a key mechanism underlying these links. This chapter will first review the observed epidemiological links between normal and abnormal diurnal and seasonal rhythmicity, cognitive impairment, and ADRD. Then it will review normal diurnal and seasonal rhythms of brain epigenetic modification and gene expression in model organisms. Finally, it will review evidence for diurnal and seasonal rhythms of epigenetic modification and gene expression the human brain in aging, Alzheimer's disease, and other brain disorders.

Seasonal plasticity of cognition and related biological measures in adults with and without Alzheimer disease: Analysis of multiple cohorts

BACKGROUND

There are few data concerning the association between season and cognition and its neurobiological correlates in older persons-effects with important translational and therapeutic implications for the diagnosis and treatment of Alzheimer disease (AD). We aimed to measure these effects.

METHODS AND FINDINGS

We analyzed data from 3,353 participants from 3 observational community-based cohort studies of older persons (the Rush Memory and Aging Project [MAP], the Religious Orders Study [ROS], and the Minority Aging Research Study [MARS]) and 2 observational memory-clinic-based cohort studies (Centre de Neurologie Cognitive [CNC] study at Lariboisière Hospital and the Sunnybrook Dementia Study [SDS]). We performed neuropsychological testing and, in subsets of participants, evaluated cerebrospinal fluid AD biomarkers, standardized structured autopsy measures, and/or prefrontal cortex gene expression by RNA sequencing. We examined the association between season and these variables using nested multiple linear and logistic regression models. There was a robust association between season and cognition that was replicated in multiple cohorts (amplitude = 0.14 SD [a measure of the magnitude of seasonal variation relative to overall variability; 95% CI 0.07-0.23], p = 0.007, in the combined MAP, ROS, and MARS cohorts; amplitude = 0.50 SD [95% CI 0.07-0.66], p = 0.017, in the SDS cohort). Average composite global cognitive function was higher in the summer and fall compared to winter and spring, with the difference equivalent in cognitive effect to 4.8 years' difference in age (95% CI 2.1-8.4, p = 0.002). Further, the odds of meeting criteria for mild cognitive impairment or dementia were higher in the winter and spring (odds ratio 1.31 [95% CI 1.10-1.57], p = 0.003). These results were robust against multiple potential confounders including depressive symptoms, sleep, physical activity, and thyroid status and persisted in cases with AD pathology. Moreover, season had a marked effect on cerebrospinal fluid Aβ 42 level (amplitude 0.30 SD [95% CI 0.10-0.64], p = 0.003), which peaked in the summer, and on the brain expression of 4 cognition-associated modules of co-expressed genes (m6: amplitude = 0.44 SD [95% CI 0.21-0.65], p = 0.0021; m13: amplitude = 0.46 SD [95% CI 0.27-0.76], p = 0.0009; m109: amplitude = 0.43 SD [95% CI 0.24-0.67], p = 0.0021; and m122: amplitude 0.46 SD [95% CI 0.20-0.71], p = 0.0012), which were in phase or anti-phase to the rhythms of cognition and which were in turn associated with binding sites for several seasonally rhythmic transcription factors including BCL11A, CTCF, EGR1, MEF2C, and THAP1. Limitations include the evaluation of each participant or sample once per annual cycle, reliance on self-report for measurement of environmental and behavioral factors, and potentially limited generalizability to individuals in equatorial regions or in the southern hemisphere.

CONCLUSIONS

Season has a clinically significant association with cognition and its neurobiological correlates in older adults with and without AD pathology. There may be value in increasing dementia-related clinical resources in the winter and early spring, when symptoms are likely to be most pronounced. Moreover, the persistence of robust seasonal plasticity in cognition and its neurobiological correlates, even in the context of concomitant AD pathology, suggests that targeting environmental or behavioral drivers of seasonal cognitive plasticity, or the key transcription factors and genes identified in this study as potentially mediating these effects, may allow us to substantially improve cognition in adults with and without AD.

Seasonal variation in hemodialysis initiation: A single-center retrospective analysis

The number of new dialysis patients has been increasing worldwide, particularly among elderly individuals. However, information on seasonal variation in hemodialysis initiation in recent decades is lacking, and the seasonal distribution of patients’ conditions immediately prior to starting dialysis remains unclear. Having this information could help in developing a modifiable approach to improving pre-dialysis care. We retrospectively investigated the records of 297 patients who initiated hemodialysis at Hiroshima Prefectural Hospital from January 1st, 2009 to December 31st, 2013. Seasonal differences were assessed by χ² or Kruskal-Wallis tests. Multiple comparison analysis was performed with the Steel test. The overall number of patients starting dialysis was greatest in winter (n = 85, 28.6%), followed by spring (n = 74, 24.9%), summer (n = 70, 23.6%), and autumn (n = 68, 22.9%), though the differences were not significant. However, there was a significant winter peak in dialysis initiation among patients aged ≥65 years, but not in those aged <65 years. Fluid overload assessed by clinicians was the most common uremic symptom among all patients, but a winter peak was only detected in patients aged ≥65 years. The body weight gain ratio showed a similar trend to fluid overload assessed by clinicians. Pulmonary edema was most pronounced in winter among patients aged ≥65 years compared with other seasons. The incidences of infection were modestly increased in summer and winter, but not statistically significant. Cardiac complications were similar in all seasons. This study demonstrated the existence of seasonal variation in dialysis initiation, with a winter peak among patients aged ≥65 years. The winter increment in dialysis initiation was mainly attributable to increased fluid overload. These findings suggest that elderly individuals should be monitored particularly closely during the winter.

Vitamin D Status Is an Independent Risk Factor for Global Cognitive Impairment in Peritoneal Dialysis Patients

Objective

Vitamin D (VD) deficiency is an independent risk factor for cognitive impairment (CI) in the general population, but VD status in peritoneal dialysis (PD) patients has not been investigated. In this study, we aimed to investigate the relationship between serum VD levels and global and specific cognitive functions in PD patients.

Design and Setting

Cross-sectional study, simultaneously conducted at two PD centers.

Patients

Clinically stable patients (n = 273) undergoing PD for at least 3 months were enrolled over a period of one year.

Main outcome Measures

Demographic and comorbidity data were recorded, and routine biochemical parameters and serum 25-hydroxyvitamin D (25(OH) D) levels of overnight fasted patients were determined. Global cognitive function was assessed by the Modified Mini-Mental State Examination (3MS) score; executive function, by the trail making tests (Trails A and B); and immediate memory, delayed memory, and language ability by the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) sub-tests.

Results

In the univariate analysis, serum 25(OH) D levels significantly correlated with 3MS scores (r = -0.139; P = 0.02), and Trail A (r = -0.188; P = 0.002) and B (r = -0.154; P = 0.01) completion times. In the multivariate analysis, 25(OH) D was found to be independently associated with global CI, but not with executive dysfunction. Serum 25(OH) D could not predict scores of immediate/delayed memory and language ability.

Conclusions

VD deficiency is highly prevalent in PD patients and is an independent risk factor for global CI in this patient cohort.

Association between serum bicarbonate and pH with depression, cognition and sleep quality in hemodialysis patients

Metabolic acidosis is a common feature in chronic renal failure patients, worsening progressively as renal function declines. There are conflicting data in hemodialysis (HD) patients with regard to acidosis, alkalosis and mortality. In HD patients, cognitive impairment, depression, sleep disorders and impaired quality of life are very common. Besides, these conditions are related with increased morbidity and mortality. However, no previous study investigated the relationship between pH, venous bicarbonate and anion gap with depression, sleep problems and cognitive function in HD patients. In this study we investigated these relationships. In total, 65 HD patients were included. The demographic parameters and laboratory parameters including bicarbonate, pH and anion gap was measured for all patients. Depressive symptoms, sleep quality and cognitive function, were measured by Beck depression inventory, The Pittsburgh Sleep Quality Index and by Mini Mental State Examination, respectively. We found that, sleep quality but not cognitive function or depression was independently related with venous pH and bicarbonate. Anion gap has no independent relationship with sleep quality, cognitive function and depression. In conclusion, metabolic acidosis and bicarbonate levels were independently related with sleep quality in HD patients. However, there was no association between metabolic acidosis and bicarbonate levels with cognitive function and depression.

[Evaluation and analysis of insomnia in chronic hemodialysis]

L'insomnie est aussi fréquente chez les hémodialysés chroniques qu'elle est négligée par le personnel soignant, davantage attelé à gérer les complications qui accompagnent l'insuffisance rénale chronique terminale et la dialyse chronique. Notre travail a eu pour but de déterminer la prévalence de l'insomnie et les facteurs qui lui sont associés, afin de pouvoir, dans un temps futur, lui dédier une stratégie de prise en charge adaptée. Il s'agit d'une étude transversale incluant 93 hémodialysés chroniques, dont nous avons étudié les données sociodémographiques, biologique, dialytiques; nous avons également collecté les caractéristiques de l'insomnie, et enfin mis en exergue les facteurs associés à sa survenue. L'insomnie a été définie par un score total supérieur ou égal à 15 au questionnaire de l'I.S.I (Insomnia Severity Index). Ainsi, la prévalence de l'insomnie est de 67,7% (n=63); l’âge moyen est de 55,6±12,7 (22-82) ans, le sexe ratio de 24 Hommes/39 Femmes, la durée moyenne en hémodialyse de 94,6 ± 58,2 (6-252) mois. 45 des patients insomniaques sont dialysés deux fois par semaine. Cette insomnie concernait le début de la nuit dans 52,3% des cas, le milieu de la nuit dans 55,5% des cas, et le petit matin dans 19,04% des cas. Les troubles associés à cette insomnie ont été: la somnolence diurne dans 79,3% des cas (n=50), le syndrome de la jambe sans repos dans 17,4% des cas (n=11), et les cauchemars dans 30,1% des cas (n=19). Une prise régulière d'hypnogènes a été notée chez 20 patients (31,7%). En analyse univariée, les facteurs associés à la survenue de l'insomnie sont l’âge avancé des patients, le sexe féminin, l'ancienneté en hémodialyse, la fréquence de deux séances de dialyse par semaine, le taux d'urée en prédialyse, le score de Charlson, la présence d'une douleur chronique (depuis plus de trois mois), la dépression et enfin l'hypertension artérielle. En analyse multivariée, on retient l’âge avancé des patients, le sexe féminin, l'ancienneté en dialyse et la fréquence de deux séances de dialyse par semaine. En conclusion, les troubles du sommeil et en particulier l'insomnie chez les hémodialysés chroniques sont fréquents et multifactoriels. Une attention particulière doit leur être accordée, incluant une collaboration régulière et étroite entre néphrologues et psychologues, psychiatres et spécialistes du sommeil.