Minimum accelerometer wear-time for reliable estimates of physical activity and sedentary behaviour of people receiving haemodialysis

From Springer Nature via Jisc Publications RouterHistory: received 2020-01-31, accepted 2020-06-01, registration 2020-06-01, online 2020-06-16, epub 2020-06-16, collection 2020-12Background: Low levels of physical activity are implicated in low life expectancies of people receiving maintenance haemodialysis. Accelerometers are increasingly being used to quantify activity behaviours of this population but guidance to quality-assure such data is lacking. The objective of this study was to provide data processing and reduction recommendations to ensure accelerometer-derived outcomes are sufficiently reliable for interpretative analysis. Methods: Seventy people receiving maintenance haemodialysis (age 55.9 ± 15.7 years, 34% women, 23% diabetic) from a single outpatient renal unit volunteered for the study. Participants wore Actigraph GT3x and ActivPAL monitors during waking hours over seven days. Reliability of accelerometer output (normalised to wear-time) was assessed via intraclass correlation coefficient (ICC). The Spearman-Brown prophecy formula was subsequently applied to the ICCs to derive the minimum required accelerometer wear-time for each behavioural outcome. Results: Monitor wear compliance was greater on dialysis compared to non-dialysis days (90% v 77%). Participants were significantly more active on non-dialysis days compared to dialysis days but there were no significant differences in estimated behaviours between days within the same condition. Average measure ICCs for all accelerometer outcomes were high (range 0.76–0.96). Computations indicated that habitual physical activity and sedentary behaviour could be estimated with a minimum reliability level of 0.80 from one dialysis day and two non-dialysis days, and at least eight hours monitor wear per day. Applying this rubric allowed 90% of participant data to be retained for further analysis. Conclusions: Regardless of accelerometer, one dialysis and two non-dialysis days data with a minimum of eight hours wear each day should enable habitual activity of people receiving maintenance haemodialysis to be characterised with acceptable reliability. These recommendations reconcile the tension between wear-time criteria stringency and retention of an adequately representative sample.21pubpu

The relative importance of frailty, physical and cardiovascular function as exercise-modifiable predictors of falls in haemodialysis patients: A prospective cohort study

From PubMed via Jisc Publications RouterTobia Zanotto - ORCID 0000-0002-6571-4763 https://orcid.org/0000-0002-6571-4763Marietta van der Linden - ORCID 000-0003-2256-6673 https://orcid.org/0000-0003-2256-6673Stage 5 chronic kidney disease (CKD-5) patients on haemodialysis (HD) are at high risk of accidental falls. Previous research has shown that frailty is one of the primary contributors to the increased risk of falling in this clinical population. However, HD patients often present with abnormalities of cardiovascular function such as baroreflex impairment and orthostatic dysregulation of blood pressure (BP) which may also be implicated in the aetiology of falling. Therefore, we aimed to explore the relative importance of frailty and cardiovascular function as potential exercise-modifiable predictors of falls in these patients. Ninety-three prevalent CKD-5 patients on HD from three Renal Units were recruited for this prospective cohort study, which was conducted between October 2015 and August 2018. At baseline, frailty status was assessed using the Fried's frailty phenotype, while physical function was evaluated through timed up and go (TUG), five repetitions chair sit-to-stand (CSTS-5), objectively measured physical activity, and maximal voluntary isometric strength. Baroreflex and haemodynamic function at rest and in response to a 60° head-up tilt test (HUT-60°) were also assessed by means of the Task Force Monitor. The number of falls experienced was recorded once a month during 12 months of follow-up. In univariate negative binomial regression analysis, frailty (RR: 4.10, 95%CI: 1.60-10.51, p = 0.003) and other physical function determinants were associated with a higher number of falls. In multivariate analysis however, only worse baroreflex function (RR: 0.96, 95%CI: 0.94-0.99, p = 0.004), and orthostatic decrements of BP to HUT-60° (RR: 0.93, 95%CI: 0.87-0.99, p = 0.033) remained significantly associated with a greater number of falls. Eighty falls were recorded during the study period and the majority of them (41.3%) were precipitated by dizziness symptoms, as reported by participants. This prospective study indicates that cardiovascular mechanisms implicated in the short-term regulation of BP showed a greater relative importance than frailty in predicting falls in CKD-5 patients on HD. A high number of falls appeared to be mediated by a degree of cardiovascular dysregulation, as evidenced by the predominance of self-reported dizziness symptoms. ClinicalTrials.gov (trial registration ID: NCT02392299; date of registration: March 18, 2015).This work was supported by a British Kidney Patient Association – British Renal Society joint grant (BKPA-BRS grant number: 16–003). The funders of this study had no role in study design; collection, analysis, and interpretation of data; writing the report; or the decision to submit the report for publication.21pubpu

Baroreflex function, haemodynamic responses to an orthostatic challenge, and falls in haemodialysis patients

From PLOS via Jisc Publications Router.History: collection 2018, received 2018-05-24, accepted 2018-11-12, epub 2018-12-06Publication status: PublishedBackground Stage 5 chronic kidney disease patients on haemodialysis (HD) often present with dizziness and pre-syncopal events as a result of the combined effect of HD therapy and cardiovascular disease. The dysregulation of blood pressure (BP) during orthostasis may be implicated in the aetiology of falls in these patients. Therefore, we explored the relationship between baroreflex function, the haemodynamic responses to a passive orthostatic challenge, and falls in HD patients. Methods Seventy-six HD patients were enrolled in this cross-sectional study. Participants were classified as “fallers” and “non-fallers” and completed a passive head up tilting to 60o (HUT-60°) test on an automated tilt table. ECG signals, continuous and oscillometric BP measurements and impedance cardiography were recorded. The following variables were derived from these measurements: heart rate (HR) stroke volume (SV), cardiac output (CO), total peripheral resistance (TPR), number of baroreceptor events, and baroreceptor effectiveness index (BEI). Results The forty-four participants who were classified as fallers (57.9%) had a lower number of baroreceptor events (6.5±8.5 vs 14±16.7, p = .027) and BEI (20.8±24.2% vs 33.4±23.3%, p = .025). In addition, fallers experienced a significantly larger drop in systolic (-6.4±10.9 vs -0.4±7.7 mmHg, p = .011) and diastolic (-2.7±7.3 vs 1.8±6 mmHg, p = .027) oscillometric BP from supine to HUT-60° compared with non-fallers. None of the variables taken for the analysis were significantly associated with falls in multivariate logistic regression analysis. Conclusions This cross-sectional comparison indicates that, at rest, HD patients with a positive history of falls present with a lower count of baroreceptor sequences and BEI. Short-term BP regulation warrants further investigation as BP drops during a passive orthostatic challenge may be implicated in the aetiology of falls in HD

A combined diabetes renal clinic improves risk factor management and progression of renal disease in a district general hospital

Aims  Aggressive management of vascular risk factors reduces the rate of progression to end-stage renal failure in patients with diabetic nephropathy. The aim of our audit was to clarify whether improvements in patient care could be demonstrated within a short time period after establishing a combined diabetes renal clinic in a district general hospital. Methods  A retrospective analysis of weight, glycaemic control, blood pressure control, rate of decline in renal function and appropriate use of medications for vascular risk management for patients in a district general hospital was performed before and after attendance at a combined diabetes renal clinic. Results  Data were complete for 45 patients. There was no significant change in weight from 14 months before attending the combined clinic, referral to the clinic and after 14 months of mean follow-up. An improvement in mean systolic blood pressure was achieved at the combined diabetes renal clinic (from 147 to 134 mmHg with an average fall of 16.5 mmHg, P &#60; 0.01). The mean glycated haemoglobin (HbA1c) improved from 8.6% to 8% (P = 0.002). The rate of decline in estimated glomerular filtration rate of 1.16 mL min−1 per month prior to referral improved to 0.21 mL min−1 per month on attending the combined clinic (P = 0.002). Conclusions  Vascular risk factor management was improved and decline in renal function slowed in patients with diabetic nephropathy within a short period of establishing a combined diabetes renal clinic in a district general hospital.</p

Baroreflex function, haemodynamic responses to an orthostatic challenge, and falls in haemodialysis patients [SP400] (Abstract)

** From Crossref via Jisc Publications Router. ** Licence for VoR version of this article starting on 18-05-2018: https://academic.oup.com/journals/pages/about_us/legal/notices Published in: Nephrology Dialysis Transplantation, Volume 33, Issue Supplement 1 (55th ERA-EDTA Congress, Copenhagen, Denmark, May 24th - 27th 2018, NDT Abstract Supplement 2018) Document number: SP400. DOI: https://doi.org/10.1093/ndt/gfy104.SP400Background: The prevalence of falls among Stage 5 chronic kidney disease (CKD-5) patients undergoing haemodialysis (HD) therapy ranges from 26.3% to 47%, and is considerably higher than in the general healthy population. In addition to traditional risk factors such as older age, frailty, comorbidity, and polypharmacy, these patients often present with dizziness and pre-syncopal events as a result of the combined effect of HD therapy and cardiovascular disease, which may contribute to an increased risk of falling. Particularly, it has been suggested that the dysregulation of blood pressure during orthostasis may play a role in the aetiology of falls in these patients. Purpose of the study: To compare the haemodynamic responses to a passive orthostatic challenge, as well as the baroreflex function, in HD patients with and without history of falls.http://www.era-edta2018.org/en-US/homehttp://www.era-edta2018.orgsch_phy33pub5380pubSuppl_

Association of postural balance and falls in adult patients receiving haemodialysis: A prospective cohort study

From Elsevier via Jisc Publications RouterBackground Static postural balance performance is often impaired in people receiving haemodialysis (HD) for the treatment of stage-5 chronic kidney disease (CKD-5). However, the question as to whether lower postural balance is associated with adverse clinical outcomes such as falls has not been addressed yet. Research question We conducted a prospective cohort study to explore the association between static postural balance and falls in people receiving HD. We hypothesised that higher postural sway would be associated with increased odds of falling. Methods Seventy-five prevalent CKD-5 patients receiving HD (age: 61.8 ± 13.4 years) from three Renal Units were enrolled in this prospective cohort study. At baseline, postural balance was assessed with a force platform in eyes open (EO) and eyes closed (EC) conditions. Centre of pressure (CoP) measures of range, velocity and area were taken for the analysis. Falls experienced by study participants were prospectively recorded during 12 months of follow-up. Secondary outcomes included timed-up and go, five-repetition sit-to-stand test and the Tinetti falls efficacy scale (FES). Results In multivariable logistic regression analysis, higher CoP range in medial-lateral direction during EC was associated with increased odds of falling (OR: 1.04, 95 %CI: 1.00−1.07, p = 0.036). In ROC curve analysis, CoP velocity in EO exhibited the greatest prognostic accuracy (AUC: 0.69, 95 %CI: 0.55−0.82), however this was not statistically different from CoP measures of area and range. None of the postural balance measures exceeded the prognostic accuracy of the FES (AUC: 0.70, 95 %CI: 0.58−0.83, p = 0.005). Significance This prospective cohort study showed that higher postural sway in medial-lateral direction was associated with increased odds of falling in people receiving HD. CoP measures of range, velocity and area displayed similar prognostic value in discriminating fallers from non-fallers. The overall utility of static posturography to detect future fall-risk may be limited in a clinical setting.82pubpu

Zeitabhaengige Vorgaenge und Schadenserkennung in Komponenten waermetechnischer Anlagen Arbeits- und Ergebnisbericht: 2. Halbj. 1983 - 1984 - 1985 1. Halbj. 1986

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