Impaired insulin secretion and glucose tolerance in β cell-selective Ca(V)1.2 Ca(2+) channel null mice

Insulin is secreted from pancreatic β cells in response to an elevation of cytoplasmic Ca(2+) resulting from enhanced Ca(2+) influx through voltage-gated Ca(2+) channels. Mouse β cells express several types of Ca(2+) channel (L-, R- and possibly P/Q-type). β cell-selective ablation of the gene encoding the L-type Ca(2+) channel subtype Ca(v)1.2 (βCa(v)1.2(–/–) mouse) decreased the whole-cell Ca(2+) current by only ∼45%, but almost abolished first-phase insulin secretion and resulted in systemic glucose intolerance. These effects did not correlate with any major effects on intracellular Ca(2+) handling and glucose-induced electrical activity. However, high-resolution capacitance measurements of exocytosis in single β cells revealed that the loss of first-phase insulin secretion in the βCa(v)1.2(–/–) mouse was associated with the disappearance of a rapid component of exocytosis reflecting fusion of secretory granules physically attached to the Ca(v)1.2 channel. Thus, the conduit of Ca(2+) entry determines the ability of the cation to elicit secretion

Prevalence and patterns of cognitive impairment in adult hemodialysis patients: the COGNITIVE-HD study

Background. Mounting evidence indicates an increased risk of cognitive impairment in adults with end-stage kidney disease on dialysis, but the extent and pattern of deficits across the spectrumof cognitive domains are uncertain. Methods. We conducted a cross-sectional study of 676 adult hemodialysis patients from 20 centers in Italy, aiming to evaluate the prevalence and patterns of cognitive impairment across five domains of learning and memory, complex attention, executive function, language and perceptual-motor function. We assessed cognitive function using a neuropsychological battery of 10 tests and calculated test and domain z-scores using population norms (age or age/education). We defined cognitive impairment as a z-score <= -1.5. Results. Participants' median age was 70.9 years (range 21.6-94.1) and 262 (38.8%) were women. Proportions of impairment on each domain were as follows: perceptual-motor function 31.5% (150/476), language 41.2% (273/662), executive function 41.7% (281/674), learning and memory 42.2% (269/638), complex attention 48.8% (329/674). Among 474 participants with data for all domains, only 28.9% (n = 137) were not impaired on any domain, with 25.9% impaired on a single domain (n = 123), 17.3% on two (n = 82), 13.9% on three (n = 66), 9.1% on four (n = 43) and 4.9% (n = 23) on all five. Across patients, patterns of impairment combinations were diverse. Conclusions. In conclusion, cognitive impairment is extremely common in hemodialysis patients, across numerous domains, and patients often experience multiple deficits simultaneously. Clinical care should be tailored to meet the needs of patients with different types of cognitive impairment and future research should focus on identifying risk factors for cognitive decline

COGNITIVE-HD study: Protocol of an observational study of neurocognitive functioning and association with clinical outcomes in adults with end-stage kidney disease treated with haemodialysis

Introduction: The prevalence of cognitive impairment may be increased in adults with end-stage kidney disease compared with the general population. However, the specific patterns of cognitive impairment and association of cognitive dysfunction with activities of daily living and clinical outcomes (including withdrawal from treatment) among haemodialysis patients remain incompletely understood. The COGNITIVE impairment in adults with end-stage kidney disease treated with HemoDialysis (COGNITIVE-HD) study aims to characterise the age-adjusted and education-adjusted patterns of cognitive impairment (using comprehensive testing for executive function, perceptual-motor function, language, learning and memory, and complex attention) in patients on haemodialysis and association with clinical outcomes. Methods and analysis: A prospective, longitudinal, cohort study of 750 adults with end-stage kidney disease treated with long-term haemodialysis has been recruited within haemodialysis centres in Italy ( July 2013 to April 2014). Testing for neurocognitive function was carried out by a trained psychologist at baseline to assess cognitive functioning. The primary study factor is cognitive impairment and secondary study factors will be specific domains of cognitive function. The primary outcome will be total mortality. Secondary outcomes will be cause-specific mortality, major cardiovascular events, fatal and non-fatal myocardial infarction and stroke, institutionalisation, and withdrawal from treatment at 12 months. Ethics and dissemination: This protocol was approved before study conduct by the following responsible ethics committees: Catania (approval reference 186/BE; 26/09/2013), Agrigento ( protocol numbers 61-62; 28/6/2013), USL Roma C (CE 39217; 24/6/2013), USL Roma F ( protocol number 0041708; 23/7/2013), USL Latina ( protocol number 20090/A001/ 2011; 12/7/2013), Trapani ( protocol number 3413; 16/ 7/2013) and Brindisi ( protocol number 40259; 6/6/ 2013). All participants have provided written and informed consent and can withdraw from the study at any time. The findings of the study will be disseminated through peer-reviewed journals and national and international conference presentations and to the participants through communication within the dialysis network in which this study is conducted

Associations of cognitive function and education level with all-cause mortality in adults on hemodialysis: Findings from the COGNITIVE-HD Study

Rationale & Objective: In the general population, cognitive impairment is associated with increased mortality, and higher levels of education are associated with lower risks for cognitive impairment and mortality. These associations are not well studied in patients receiving long-term hemodialysis and were the focus of the current investigation. Study Design: Prospective cohort study. Setting & Participants: Adult hemodialysis patients treated in 20 Italian dialysis clinics. Exposures: Patients’ cognitive function across 5 domains (memory, attention, executive function, language, and perceptual-motor function), measured using a neuropsychological assessment comprising 10 tests; and patients’ self-reported years of education. Outcome: All-cause mortality. Analytical Approach: Nested multivariable Cox regression models were used to examine associations of cognition (any domain impaired, number of domains impaired, and global function score from principal components analysis of unadjusted test scores) and education with mortality and whether there were interactions between them. Results: 676 (70.6%) patients participated, with a median age of 70.9 years and including 38.8% women. Cognitive impairment was present in 79.4% (527/664; 95% CI, 76.3%-82.5%). During a median follow-up of 3.3 years (1,874 person-years), 206 deaths occurred. Compared to no cognitive impairment, adjusted HRs for mortality were 1.77 (95% CI, 1.07-2.93) for any impairment, 1.48 (95% CI, 0.82-2.68) for 1 domain impaired, 1.88 (95% CI, 1.01-3.53) for 2 domains, and 2.01 (95% CI, 1.14-3.55) for 3 to 5 domains. The adjusted HR was 0.68 (95% CI, 0.51-0.92) per standard deviation increase in global cognitive function score. Compared with primary or lower education, adjusted HRs were 0.79 (95% CI, 0.53-1.20) for lower secondary and 1.13 (95% CI, 0.80-1.59) for upper secondary or higher. The cognition-by-education interaction was not significant (P = 0.7). Limitations: Potential selection bias from nonparticipation and missing data; no data for cognitive decline; associations with education were not adjusted for other socioeconomic factors. Conclusions: Cognitive impairment is associated with premature mortality in hemodialysis patients. Education does not appear to be associated with mortality

Oral disease in adults treated with hemodialysis: prevalence, predictors, and association with mortality and adverse cardiovascular events: the rationale and design of the ORAL Diseases in hemodialysis (ORAL-D) study, a prospective, multinational, longitu

Background: People with end-stage kidney disease treated with dialysis experience high rates of premature death that are at least 30-fold that of the general population, and have markedly impaired quality of life. Despite this, interventions that lower risk factors for mortality (including antiplatelet agents, epoetins, lipid lowering, vitamin D compounds, or dialysis dose) have not been shown to improve clinical outcomes for this population. Although mortality outcomes may be improving overall, additional modifiable determinants of health in people treated with dialysis need to be identified and evaluated.Oral disease is highly prevalent in the general population and represents a potential and preventable cause of poor health in dialysis patients. Oral disease may be increased in patients treated with dialysis due to their lower uptake of public dental services, as well as increased malnutrition and inflammation, although available exploratory data are limited by small sample sizes and few studies evaluating links between oral health and clinical outcomes for this group, including mortality and cardiovascular disease. Recent data suggest periodontitis may be associated with mortality in dialysis patients and well-designed, larger studies are now required. Methods/design. The ORAL Diseases in hemodialysis (ORAL-D) study is a multinational, prospective (minimum follow-up 12 months) study. Participants comprise consecutive adults treated with long-term in-center hemodialysis. Between July 2010 and February 2012, we recruited 4500 dialysis patients from randomly selected outpatient dialysis clinics in Europe within a collaborative network of dialysis clinics administered by a dialysis provider, Diaverum, in Europe (France, Hungary, Italy, Poland, Portugal, and Spain) and South America (Argentina). At baseline, dental surgeons with training in periodontology systematically assessed the prevalence and characteristics of oral disease (dental, periodontal, mucosal, and salivary) in all participants. Oral hygiene habits and thirst were evaluated using self-administered questionnaires. Data for hospitalizations and mortality (total and cause-specific) according to baseline oral health status will be collected once a year until 2022. Discussion. This large study will estimate the prevalence, characteristics and correlations of oral disease and clinical outcomes (mortality and hospitalization) in adults treated with dialysis. We will further evaluate any association between periodontitis and risk of premature death in dialysis patients that has been suggested by existing research. The results from this study should provide powerful new data to guide strategies for future interventional studies for preventative and curative oral disease strategies in adults who have end-stage kidney disease

Prevalence and correlates of self-reported sexual dysfunction in CKD: A meta-analysis of observational studies

Background: Sexual dysfunction is an under-recognized problem in men and women with chronic kidney disease (CKD). The prevalence, correlates, and predictors of this condition in patients with CKD have not been evaluated comprehensively. Study Design Systematic review and meta-analysis. Setting & Population Patients treated using dialysis (dialysis patients), patients treated using transplant (transplant recipients), and patients with CKD not treated using dialysis or transplant (nondialysis nontransplant patients with CKD). Selection Criteria for Studies Observational studies conducted in patients with CKD only or including a control group without CKD. Predictor Type of study population. Outcomes Sexual dysfunction in men and women with CKD using validated tools, such as the International Index of Erectile Function, the Female Sexual Function Index (FSFI), or other measures as reported by study investigators. Results 50 studies (8,343 patients) of variable size (range, 16-1,023 patients) were included in this review. Almost all studies explored sexual dysfunction in men and specifically erectile dysfunction. The summary estimate of erectile dysfunction in men with CKD was 70% (95% CI, 62%-77%; 21 studies, 4,389 patients). Differences in reported prevalence rates of erectile dysfunction between different studies were attributable primarily to age, study populations, and type of study tool used to assess the presence of erectile dysfunction. In women, the reported prevalence of sexual dysfunction was assessed in only 306 patients from 2 studies and ranged from 30%-80%. Compared with the general population, women with CKD had a significantly lower overall FSFI score (8 studies or subgroups, 407 patients; mean difference, -9.28; 95% CI, -12.92 to -5.64). Increasing age, diabetes mellitus, and depression consistently were found to correlate with sexual dysfunction in 20 individual studies of patients with CKD using different methods. Limitations Suboptimal and lack of uniform assessment of outcome measures. Conclusions Sexual dysfunction is highly prevalent in both men and women with CKD, especially among those on dialysis. Larger studies enrolling different ethnic groups, using validated study tools, and analyzing the influence of various factors on the development of sexual dysfunction are needed

Oral mucosal lesions and risk of all-cause and cardiovascular mortality in people treated with long-term haemodialysis: the ORAL-D multinational cohort study

Chronic kidney disease is a risk factor for oral diseases, which may be associated with premature death. We evaluated the risk of all-cause and cardiovascular mortality associated with oral mucosal lesions in adults with kidney failure treated with long-term haemodialysis.Oral mucosal lesions (herpes, ulceration, neoformation, white lesion, red lesion, oral candidiasis, geographical tongue, petechial lesions, and fissured tongue) were evaluated within the Oral Diseases in Haemodialysis (ORAL-D) study, a multinational cohort study of 4726 haemodialysis adults. We conducted cox regression analyses adjusted for demographic and clinical variables to evaluate the association with all-cause and cardiovascular mortality.Overall, 4205 adults (mean age 61.6 ± 15.6 years) underwent oral mucosal examination with 40% affected by at least one lesion. The prevalence of oral lesions was (in order of frequency): oral herpes 0.5%, mucosal ulceration 1.7%, neoformation 2.0%, white lesion 3.5%, red lesion 4.0%, oral candidiasis 4.6%, geographical tongue 4.9%, petechial lesions 7.9%, and fissured tongue 10.7%. During median follow-up of 3.5 years, 2114 patients died (1013 due to cardiovascular disease). No association was observed between any individual oral lesion and all-cause or cardiovascular mortality when adjusted for comorbidities, except for oral candidiasis, which was associated with all-cause mortality (adjusted hazard ratio 1.37, 95% CI 1.00 to 1.86) and cardiovascular mortality (adjusted hazard ratio 1.64, 95% CI 1.09 to 2.46).Oral mucosal lesions are prevalent in haemodialysis patients. Oral candidiasis appears to be a risk factor for death due to cardiovascular diseases