Kidney function, gait pattern and fall in the general population: a cohort study

Mobility-related brain regions linking carotid intima-media thickness to specific gait performances in old age

BACKGROUND

Gait disturbance is common in older adults with vascular diseases. However, how carotid atherosclerosis affects gait remains poorly understood. The objectives were to investigate the associations between carotid intima-media thickness and specific gait performances and explore the potential role of brain structure in mediating these associations.

METHODS

A cross-sectional analysis of data from the Taizhou Imaging Study was conducted, including 707 individuals who underwent both gait and carotid ultrasound examinations. Gait assessments include the Timed-Up-and-Go test, the Tinetti test, and quantitative gait assessment using a wearable device. Quantitative parameters were summarized into independent gait domains with factor analysis. Magnetic resonance images were obtained on a 3.0-Tesla scanner, and the volumes of fifteen brain regions related to motor function (primary motor, sensorimotor), visuospatial attention (inferior posterior parietal lobules, superior posterior parietal lobules), executive control function (dorsolateral prefrontal cortex, anterior cingulate), memory (hippocampus, entorhinal cortex), motor imagery (precuneus, parahippocampus, posterior cingulated cortex), and balance (basal ganglia: pallidum, putamen, caudate, thalamus) were computed using FreeSurfer and the Desikan-Killiany atlas. Mediation analysis was conducted with carotid intima-media thickness as the predictor and mobility-related brain regions as mediators.

RESULTS

Carotid intima-media thickness was found to be associated with the Timed-Up-and-Go performance (β = 0.129, p = 0.010) as well as gait performances related to pace (β=-0.213, p < 0.001) and symmetry (β = 0.096, p = 0.045). Besides, gait performances were correlated with mobility-related brain regions responsible for motor, visuospatial attention, executive control, memory, and balance (all FDR < 0.05). Notably, significant regions differed depending on the gait outcomes measured. The primary motor (41.9%), sensorimotor (29.3%), visuospatial attention (inferior posterior parietal lobules, superior posterior parietal lobules) (13.8%), entorhinal cortex (36.4%), and motor imagery (precuneus, parahippocampus, posterior cingulated cortex) (27.3%) mediated the association between increased carotid intima-media thickness and poorer Timed-Up-and-Go performance. For the pace domain, the primary motor (37.5%), sensorimotor (25.8%), visuospatial attention (12.3%), entorhinal cortex (20.7%), motor imagery (24.9%), and balance (basal ganglia: pallidum, putamen, caudate, thalamus) (11.6%) acted as mediators.

CONCLUSIONS

Carotid intima-media thickness is associated with gait performances, and mobility-related brain volume mediates these associations. Moreover, the distribution of brain regions regulating mobility varies in the different gait domains. Our study adds value in exploring the underlying mechanisms of gait disturbance in the aging population.

Novel risk-factor analysis and risk-evaluation model of falls in patients receiving maintenance hemodialysis

This study investigated the prevalence of falls in maintenance hemodialysis (MHD) patients, and established a nomogram model for evaluating the fall risk of MHD patients. This study enrolled 303 MHD patients from the dialysis department of a tertiary hospital in July 2021. The general data of the participants, as well as the scores on the FRAIL scale, Sarcopenia Screening Questionnaire (SARC-F), Short Physical Performance Battery (SPPB) Scale, and of anxiety and depression, and the occurrence of falls were recorded. Using R language, data were assigned to the training set (n = 212) and test set (n = 91), and a logistic regression model was established. The regression model was verified by the receiver operating characteristic (ROC) curve, area under the curve (AUC), and the calibration curve. As a result, the prevalence of falls in MHD patients was 20.46%. Risk factors for falls in the optimal multivariate logistic regression model included hearing impairment, the depression score, and the SPPB score, of which a higher depression score (odds ratio (OR): 1.28, 95% confidence interval (CI): 1.09-1.49, p = 0.002) and SPPB ≤ 6 (OR_vsSPPB9-12: 3.69, 95% CI: 1.04-13.14, p = 0.043) conferred independent risk for falls. AUC of the nomogram in the training was 0.773, which in the test group was 0.663. The calibration and standard curves were fitted closely, indicated that the evaluation ability of the model was good. Thus, a higher depression score and SPPB ≤ 6 are independent risk factors for falls in MHD patients, and the nomogram with good accuracy and discrimination that was established in this study has clinical application value.

Serum bicarbonate levels and gait abnormalities in older adults: a cross-sectional study

Metabolic acidosis is associated with impaired physical function in patients with chronic kidney disease (CKD) and older adults. However, whether acidosis is associated with gait abnormalities has received little attention. In a cohort of 323 community-dwelling adults ≥ 65 years old who underwent quantitative gait analysis, we examined associations of serum bicarbonate with eight individual gait variables. After multivariable adjustment, participants in the lowest bicarbonate tertile (< 25 mEq/L) had 8.6 cm/s slower speed (95% confidence interval [CI] 3.2–13.9), 7.9 cm shorter stride length (95% CI 3.5–12.2), and 0.03 s longer double support time (95% CI 0.002–0.1) compared with those in the middle tertile (25–27 mEq/L). Furthermore, lower bicarbonate levels were associated with more severe gait abnormalities in a graded manner. After further adjustment for possible mediating factors, associations were attenuated but remained significant. Among participants with CKD, associations were of similar or greater magnitude compared with those without CKD. Factor analysis was performed to synthesize the individual gait variables into unifying domains: among the pace, rhythm, and variability domains, lower serum bicarbonate was associated with worse performance in pace. In sum, lower serum bicarbonate was independently associated with worse performance on several quantitative measures of gait among older adults.

Step length and fall risk in adults with chronic kidney disease: a pilot study

Background

Patients with chronic kidney disease commonly experience gait abnormalities, which predispose to falls and fall-related injuries. An unmet need is the development of improved methods for detecting patients at high risk of these complications, using tools that are feasible to implement in nephrology practice. Our prior work suggested step length could be such a marker. Here we explored the use of step length as a marker of gait impairment and fall risk in adults with chronic kidney disease.

Methods

We performed gait assessments in 2 prospective studies of 82 patients with stage 4 and 5 chronic kidney disease (n = 33) or end-stage renal disease (ESRD) (n = 49). Gait speed and step length were evaluated during the 4-m walk component of the Short Physical Performance Battery (SPPB). Falls within 6 months prior to or following enrollment were identified by questionnaire. Associations of low step length (≤47.2 cm) and slow gait speed (≤0.8 m/s) with falls were examined using logistic regression models adjusted for demographics and diabetes and peripheral vascular disease status.

Results

Assessments of step length were highly reproducible (r = 0.88, p < 0.001 for duplicate measurements at the same visit; r = 0.78, p < 0.001 between baseline and 3-month evaluations). Patients with low step length had poorer physical function, including lower SPPB scores, slower gait speed, and lower handgrip strength. Although step length and gait speed were highly correlated (r = 0.73, p < 0.001), one-third (n = 14/43) of patients with low step length did not have slow gait speed. Low step length and slow gait speed were each independently associated with the likelihood of falls (odds ratio (OR) 3.90 (95% confidence interval (CI) 1.05–14.60) and OR 4.25 (95% CI 1.24–14.58), respectively). Compared with patients who exhibited neither deficit, those with both had a 6.55 (95% CI 1.40–30.71) times higher likelihood of falls, and the number of deficits was associated with a graded association with falls (p trend = 0.02). Effect estimates were similar after further adjustment for ESRD status.

Conclusions

Step length and gait speed may contribute additively to the assessment of fall risk in a general adult nephrology population.

Gait disorders in CKD patients: muscle wasting or cognitive impairment? A cross-sectional pilot study to investigate gait signatures in Stage 1-5 CKD patients

Background

Instrumental gait analysis in nephrology is widely neglected, although patients with chronic kidney disease (CKD) show brain changes due to cerebrovascular disease and metabolic disorders that can potentially influence gait quality. Our study assesses the association between CKD stages and gait parameters, to understand the prevalent status of brain related gait parameters (i.e. variability) and of performance related parameters (i.e. gait speed, stride length). We hypothesize that gait changes are detectable already in early stages of CKD.

Methods

Forty-five participants distributed in 5 CKD severity groups underwent an instrumental gait analysis via a triaxial accelerometer affixed to the lower trunk under single- and dual-task conditions. In addition to spatio-temporal parameters, variability and dual-task cost of gait were extracted. A battery of clinical assessments was conducted with the aim of helping to better explain the findings of the gait analysis. A correlation analysis was made to investigate a linear relation between gait parameters and CKD severity.

Results

Statistically significant correlations (Pearson correlation coefficient) with CKD severity were found for gait speed (p < 0.01, r = -0.55, 95% CI [-0.73;-0.30]), stride length ( p < 0.01, r = -0.40, 95% CI [-0.62;-0.12]), step length (p < 0.01, r = -0.41, 95% CI [-0.63;-0.13], coefficient of variance (CV) of step length (p = 0.01, r = 0.36, 95% CI [0.08;0.59]), gait regularity (p < 0.01, r = -0.38, 95% CI [-0.61;-0.10]), dual-task cost of gait speed (p < 0.01, r = 0.40, 95% CI [0.13;0.62]) and dual-task cost of stride time (p = 0.03, r = 0.32, 95% CI [0.03;0.57]). Adjustment for age and gender confirmed all results except for gait regularity. With increasing severity of renal failure, Handgrip strength, Time for the Expanded Timed Get Up and Go test, executive functions, haemoglobin, and haematocrit, worsen.

Conclusions

The correlation of CKD severity with spatio-temporal parameters (performance indices mainly relatable to peripheral functionality) and with variability of gait (related to central factors) supported by the results of the clinical assessments, suggests that gait disturbance in CKD patients is not only due to metabolic factors that lead to muscle wasting, but also to brain changes that affect motor control. This suggests that the treatment of renal disease should include cognitive aspects in addition to metabolic and functional factors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02697-8.

Unraveling the Association Between Gait and Mortality-One Step at a Time

BACKGROUND

Slowness of walking is one of the very first signs of aging and is considered a marker for overall health that is strongly associated with mortality risk. In this study, we sought to disentangle the clinical drivers of the association between gait and mortality.

METHODS

We included 4,490 participants of the Rotterdam Study who underwent a gait assessment between 2009 and 2015 and were followed-up for mortality until 2018. Gait was assessed with an electronic walkway and summarized into the domains Rhythm, Phases, Variability, Pace, Tandem, Turning, and Base of Support. Cox models adjusted for age, sex, and height were built and consecutively adjusted for six categories of health indicators (lifestyle, musculoskeletal, cardiovascular, pulmonary, metabolic, and neurological). Analyses were repeated in comorbidity-free individuals.

RESULTS

Multiple gait domains were associated with an increased risk of mortality, including Pace (hazard ratio (HR) per SD worse gait, adjusted for other domains: 1.34 [1.19-1.50]), Rhythm (HR: 1.12 [1.02-1.23]) and Phases (HR: 1.12 [1.03-1.21]). Similarly, a 0.1 m/s decrease in gait speed was associated with a 1.21 (1.15-1.27) times higher hazard of mortality (HR fully adjusted: 1.14 [1.08-1.20]). In a comorbidity-free subsample, the HR per 0.1 m/s decrease in gait speed was 1.25 (1.09-1.44). Cause-specific mortality analyses revealed an association between gait speed and multiple causes of death.

CONCLUSIONS

Several gait domains were associated with mortality risk, including Pace which primarily represents gait speed. The association between gait speed and mortality persisted after an extensive adjustment for covariates, suggesting that gait is a marker for overall health.

Walking while Talking in Older Adults with Chronic Kidney Disease

BACKGROUND AND OBJECTIVES

Walking while talking is a dual cognitive-motor task that predicts frailty, falls, and cognitive decline in the general elderly population. Adults with CKD have gait abnormalities during usual walking. It is unknown whether they have greater gait abnormalities and cognitive-motor interference during walking while talking.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Community-dwelling, nondisabled adults (n=330) ≥65 years of age underwent quantitative gait analysis, including walking while talking. Differences in walking-while-talking performance by CKD status were evaluated, and relative changes between walking-while-talking and walking alone performance were computed to quantify cognitive-motor interference (dual-task cost). Associations were tested using multivariable linear spline regression models, and independent gait domains were derived using factor analysis. CKD was defined as an eGFR<60 ml/min per 1.73 m2.

RESULTS

CKD was present in 134 (41%) participants. Participants with CKD had slower gait speed along with various gait cycle abnormalities during walking while talking: among those with CKD, every 10-ml/min per 1.73 m2 lower eGFR was associated with 3.3-cm/s (95% confidence interval, 0.4 to 6.1) slower gait speed, 1.8-cm (95% confidence interval, 0.6 to 3.0) shorter step length, 1.1% (95% confidence interval, 0.6 to 1.7) less time in the swing phase, and 1.4% (95% confidence interval, 0.5 to 2.3) greater time in double support after multivariable adjustment. When comparing walking while talking with walking alone, every 10-ml/min per 1.73 m2 lower eGFR was associated with 1.8% (95% confidence interval, 0.5 to 3.2) greater decrease in time in the swing phase and 0.9% (95% confidence interval, 0.2 to 1.5) greater increase in time in the stance phase. Factor analysis identified three walking-while-talking domains and three dual-task cost domains: eGFR was associated specifically with the rhythm domain for both walking-while-talking and dual-task cost. Every 10-ml/min per 1.73 m2 lower eGFR was associated with a poorer performance of 0.2 SD (95% confidence interval, 0.1 to 0.3) for walking while talking and 0.2 SD (95% confidence interval, 0.03 to 0.3) for dual-task cost.

CONCLUSIONS

During walking while talking, CKD is associated with gait abnormalities, possibly due to increased cognitive-motor interference.

Long-term gait measurements in daily life: Results from the Berlin Aging Study II (BASE-II)

Background

Walking ability is an important prerequisite for activity, social participation and independent living. While in most healthy adults, this ability can be assumed as given, limitations in walking ability occur with increasing age. Furthermore, slow walking speed is linked to several chronic conditions and overall morbidity. Measurements of gait parameters can be used as a proxy to detect functional decline and onset of chronic conditions. Up to now, gait characteristics used for this purpose are measured in standardized laboratory settings. There is some evidence, however, that long-term measurements of gait parameters in the living environment have some advantages over short-term laboratory measurements.

Methods

We evaluated cross-sectional data from an accelerometric sensor worn in a subgroup of 554 participants of the Berlin Aging Study II (BASE-II). Data from the two BASE-II age groups (age between 22–36 years and 60–79 years) were used for the current analysis of accelerometric data for a minimum of two days and a maximum of ten days were available. Real world walking speed, number of steps, maximum coherent distance and total distance were derived as average data per day. Linear regression analyses were performed on the different gait parameters in order to identify significant determinants. Additionally, Mann-Whitney-U-tests were performed to detect sex-specific differences.

Results

Age showed to be significantly associated with real world walking speed and with the total distance covered per day, while BMI contributed negatively to the number of walking steps, maximum coherent distance and total distance walked. Additionally, sex was associated with walking steps. However, R²-values for all models were low. Overall, women had significantly more walking steps and a larger coherent distance per day when compared to men. When separated by age group, this difference was significant only in the older participants. Additionally, walking speed was significantly higher in women compared to men in the subgroup of older people.

Conclusions

Age- and sex-specific differences have to be considered when objective gait parameters are measured, e.g. in the context of clinical risk assessment. For this purpose normative data, differentiating for age and sex would have to be established to allow reliable classification of long-term measurements of gait.

Accidental falling in community-dwelling elderly with chronic kidney disease

PURPOSE

The aim of the current study was to evaluate the association between a decreased estimated glomerular filtration rate (eGFR) and accidental falling in elderly patients who visited the day clinic of the department of geriatric medicine of the University of Medical Center Utrecht (UMCU).

STUDY DESIGN

A cross-sectional analysis with people aged ≥ 65 years of the Utrecht Cardiovascular Cohort was performed. Patients were stratified into different stages of kidney disease (< 45, 45-59, and ≥ 60 ml/min per 1.73 m2). Logistic regression models were used to evaluate the association between chronic kidney disease and falling.

RESULTS

Our analysis included 1000 participants with a mean age 79.4 (± 6.6) years, of whom 38% had an eGFR of < 60 ml/min per 1.73 m2 and 17% < 45 ml/min per 1.73 m2. Univariate analysis showed a significant higher prevalence [odds ratio 1.75 (95% confidence interval 1.21-2.53; p ≤ 0.01)] of falling in the population with an eGFR < 45 ml/min per 1.73 m2 compared to patients with an eGFR ≥ 60 ml/min per 1.73 m2. After correcting for multiple potential confounders in the multivariate analysis, this association was no longer present.

CONCLUSIONS

In geriatric patients ≥ 65 years, patients with a decreased eGFR fall more often than patients with a preserved kidney function. This seems to be related with the risk profile of patients with CKD and not with a decreased eGFR itself, as after correcting for potential confounders no association remained. Nevertheless, accidental falling is a highly prevalent problem in the elderly CKD population. Therefore, nephrologists should actively ask about accidental falling, and thereby screen for high-risk patients.