Neuromuscular complications of kidney diseases

Sarcopenia is associated with mild-to-moderate chronic kidney disease in Chinese community-dwelling older men but not in women

OBJECTIVE

To determine whether a relationship exists between sarcopenia, including its individual components (muscle mass, muscle strength and gait speed), and mild-to-moderate chronic kidney disease (CKD) in Chinese older adults.

METHODS

This cross-sectional study comprised participants aged ≥60 years from Tianjin and Shanghai, China, who joined a national free physical examination program between 2014 and 2019, and consented to study inclusion. Sarcopenia was defined according to the Asian Working Group for Sarcopenia (2019 version). Mild-to-moderate CKD was defined as estimated glomerular filtration rate (eGFR) between 45 ml/min/1.73 m² and 60 ml/min/1.73 m².

RESULTS

A total of 1627 participants were included (mean age, 69.32 ± 6.17 years; 43.8% male). Sarcopenia was significantly associated with mild-to-moderate CKD in men but not women. Among three physical performance components, slow gait speed (odds ratio 1.89, 95% confidence interval 1.38, 2.58) was associated with mild-to-moderate CKD in both men and women after adjusting for all other variables.

CONCLUSIONS

Sarcopenia was closely associated with mild-to-moderate CKD in older men, and slow gait speed was related to mild-to-moderate CKD in men and women. These findings may help guide better diagnosis and management of CKD in the context of slow gait speed, and facilitate earlier CKD detection and appropriate intervention in older adults.

Different stages of chronic kidney disease are associated with physical performance in adults over 60 years

Objective

The purpose of this study was to determine the association between different stages of chronic kidney disease (CKD) and sarcopenia and its components in the Chinese older population.

Methods

The study comprised of 2,213 participants aged ≥ 60 years (1,025 men; mean age: 70.7 years) recruited from Shanghai who were invited to participate in a comprehensive geriatric assessment. Sarcopenia was defined according to the AWGS 2019 consensus update on sarcopenia diagnosis criteria. The glomerular filtration rate (GFR) was estimated using the equation that originated from the CKD-EPI equation, the stages of CKD are classified according to the Kidney Disease-Improving Global Outcomes (KDIGO).

Results

The overall prevalence of sarcopenia was 19.0%, which increased with the severity of CKD. The prevalence of sarcopenia in patients with CKD 3-4 and kidney failure was significantly higher than that in normal and CKD 1-2 (p < 0.05). In logistic regression analysis model, compared with normal and CKD 1 patients, kidney failure was significantly associated with the increased risk of sarcopenia and low grip strength (p < 0.05); CKD 2, CKD 3-4 and kidney failure groups were significantly associated with an increased risk of low walking speed (p < 0.05), respectively; while the association between CKD and muscle mass was not shown.

Conclusions

In our study, only decreased physical performance, as represented by walking speed, was significantly associated with increased CKD severity. This may improve the evidence for the prevention and intervention of sarcopenia in patients with CKD.

The role of urea in neuronal degeneration and sensitization: An in vitro model of uremic neuropathy

Background

Uremic neuropathy commonly affects patients with chronic kidney disease, with painful sensations in the feet, followed by numbness and weakness in the legs and hands. The symptoms usually resolve following kidney transplantation, but the mechanisms of uremic neuropathy and associated pain symptoms remain unknown. As blood urea levels are elevated in patients with chronic kidney disease, we examined the morphological and functional effects of clinically observed levels of urea on sensory neurons.

Methods

Rat dorsal root ganglion neurons were treated with 10 or 50 mmol/L urea for 48 h, fixed and immunostained for PGP9.5 and βIII tubulin immunofluorescence. Neurons were also immunostained for TRPV1, TRPM8 and Gap43 expression, and the capsaicin sensitivity of urea- or vehicle-treated neurons was determined.

Results

Urea-treated neurons had degenerating neurites with diminished PGP9.5 immunofluorescence, and swollen, retracted growth cones. βIII tubulin appeared clumped after urea treatment. After 48 hours urea treatment, neurite lengths were significantly reduced to 60 ± 2.6% (10 mmol/L, **P < 0.01), and to 56.2 ± 3.3% (50 mmol/L, **P < 0.01), compared with control neurons. Fewer neurons survived urea treatment, with 70.08 ± 13.3% remaining after 10 mmol/L (*P < 0.05) and 61.49 ± 7.4% after 50 mmol/L urea treatment (**P < 0.01), compared with controls. The proportion of neurons expressing TRPV1 was reduced after urea treatment, but not TRPM8 expressing neurons. In functional studies, treatment with urea resulted in dose-dependent neuronal sensitization. Capsaicin responses were significantly increased to 115.29 ± 3.4% (10 mmol/L, **P < 0.01) and 125.3 ± 4.2% (50 mmol/L, **P < 0.01), compared with controls. Sensitization due to urea was eliminated in the presence of the TRPV1 inhibitor SB705498, the mitogen-activated protein kinase kinase inhibitor PD98059, the PI3 kinase inhibitor LY294002 and the TRPM8 inhibitor N-(3-Aminopropyl)-2-[(3-methylphenyl)methoxy]-N-(2-thienylmethyl)benzamide (AMTB hydrochloride).

Conclusion

Neurite degeneration and sensitization are consistent with uremic neuropathy and provide a disease-relevant model to test new treatments.

Randomized Controlled Trial of Exercise in CKD-The RENEXC Study

Introduction

Home-based, clinically feasible trials in non-dialysis-dependent patients with chronic kidney disease (CKD) are sparse. We compared the effects of 2 different exercise training programs on physical performance, and measured glomerular filtration rate (mGFR) and albuminuria level in patients with CKD stages 3 to 5.

Methods

This is a single-center, randomized controlled trial (RCT) comprising 151 patients (mGFR: 22 ± 8 ml/min per 1.73 m²; age 66 ± 14 years) randomized to either balance or strength training. Both groups were prescribed 30 minutes of exercise per day for 5 days per week for 12 months, comprising 60 minutes per week of endurance training and 90 minutes per week of either strength or balance exercises. The exercises were individually prescribed, and the intensity was monitored with Borg's rating of perceived exertion (RPE).

Results

There were no treatment differences for any of the primary outcomes measuring physical performance. The strength and balance groups showed significantly increased effect sizes after 12 months for the following: walking (31 m and 24 m, P < 0.001) and the 30-second sit-to-stand test (both: 1 time, P < 0.001); quadriceps strength (right/left: strength 1.2/0.8 kg*m, P < 0.003; balance 0.6/0.9, P < 0.01); functional reach (both: 2 cm, P < 0.01); and fine motor skills (open/closed eyes, right/left, both: between 0.3 and 4 seconds faster, P < 0.05). After 12 months, there was a significant treatment difference for albuminuria (P < 0.02), which decreased by 33% in the strength group. In both groups, mGFR declined by 1.8 ml/min per 1.73 m².

Conclusion

Our primary hypothesis that strength training was superior to balance training was not confirmed. Within groups, 12 months of exercise training resulted in significant improvements in most measures of physical performance. Measured GFR declined similarly in the 2 groups. The strength group showed a significant decrease in albuminuria.

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

Background

Gait disturbance is proposed as a mechanism for higher risk of fall in kidney disease patients. We investigated the association of kidney function with gait pattern in the general population and tested whether the association between impaired kidney function and fall is more pronounced in subjects with lower gait function.

Methods

We included 1430 participants (mean age: 60 years) from the Rotterdam Study. Kidney function was assessed using estimated glomerular filtration rate (eGFR) and albumin-to-creatinine ratio (ACR). We assessed global gait, gait velocity and seven independent gait domains: Rhythm, Phases, Variability, Pace, Tandem, Turning and Base of Support. Regression models adjusted for cardiometabolic and neurological factors were used. We evaluated whether participants with impaired kidney function and impaired gait fell more in the previous year.

Results

The study population had a median (interquartile range) ACR of 3.6 (2.5-6.2) mg/g and mean ± SD eGFR of 87.6 ± 15 mL/min/1.73 m2. Higher ACR and lower eGFR were associated with lower global gait score [per doubling of ACR: -0.10, 95% confidence interval (CI): -0.14 to -0.06, and per SD eGFR:-0.09, 95% CI: -0.14 to -0.03] and slower gait speed (ACR: -1.44 cm/s, CI: -2.12 to -0.76; eGFR: -1.55 cm/s, CI: -2.43 to -0.67). Worse kidney function was associated with lower scores in Variability domain. The association between impaired kidney function and history of fall was present only in participants with lower gait scores [odds ratio (95% CI): ACR: 1.34 (1.09-1.65); eGFR: 1.58 (1.07-2.33)].

Conclusions

We observed a graded association between lower kidney function and impaired gait suggesting that individuals with decreased kidney function, even at an early stage, need to be evaluated for gait abnormalities and might benefit from fall prevention programmes.

Neurologic manifestations of acute and chronic renal disease

Acute and chronic renal disease is prevalent in hospitalized and ambulatory patient populations. Most patients with acute or chronic renal disease exhibit some degree of neurologic dysfunction affecting the CNS, peripheral nervous system, or both. Neurologic manifestations may be a direct consequence of the uremic state or a consequence of renal replacement therapy. Early recognition of common central and peripheral nervous system dysfunction as it relates to renal disease may provide opportunities for therapeutic intervention and improved outcomes. This review will summarize the most frequently encountered manifestations of acute and chronic renal disease, organized with respect to their occurrence as a direct consequence of advanced renal dysfunction or renal replacement therapy.

Neurologic manifestations in Sagliker syndrome: uglifying human face appearance in severe and late secondary hyperparathyroidism in chronic renal failure patients

Patients with chronic renal failure (CRF) often have signs and symptoms related to fluid and electrolyte disturbances, anemia, malnutrition, bone disease, and gastrointestinal problems. Vascular and neurologic impairment in particular remain an important source of morbidity and mortality in this vulnerable patient population. Sagliker syndrome is a novel syndrome that was recently described in 2004 in patients with CRF and severe and late secondary hyperparathyroidism who suffered from severe skull and facial bone changes, particularly from uglifying human face appearances and neuropsychiatric disorders. The goal of this study was to assess neuropsychiatric manifestations occurring in CRF patients with Sagliker syndrome. Four female and 8 male patients with CRF on regular dialysis at the hemodialysis units of the Internal Medicine Departments around southern Turkey participated in the study. All patients underwent a clinical neurologic examination performed by the same neurologist. Neuropsychiatric signs and symptoms were found in all cases. The results showed that the most frequent neurologic manifestations in CRF patients with Sagliker syndrome were headache, polyneuropathy, cranial neuropathy, fatigue, and psychiatric disorders.

Neurological complications in renal failure: a review

Neurological complications whether due to the uremic state or its treatment, contribute largely to the morbidity and mortality in patients with renal failure. Despite continuous therapeutic advances, many neurological complications of uremia, like uremic encephalopathy, atherosclerosis, neuropathy and myopathy fail to fully respond to dialysis. Moreover, dialytic therapy or kidney transplantation may even induce neurological complications. Dialysis can directly or indirectly be associated with dialysis dementia, dysequilibrium syndrome, aggravation of atherosclerosis, cerebrovascular accidents due to ultrafiltration-related arterial hypotension, hypertensive encephalopathy, Wernicke's encephalopathy, hemorrhagic stroke, subdural hematoma, osmotic myelinolysis, opportunistic infections, intracranial hypertension and mononeuropathy. Renal transplantation itself can give rise to acute femoral neuropathy, rejection encephalopathy and neuropathy in graft versus host disease. The use of immunosuppressive drugs after renal transplantation can cause encephalopathy, movement disorders, opportunistic infections, neoplasms, myopathy and progression of atherosclerosis. We address the clinical, pathophysiological and therapeutical aspects of both central and peripheral nervous system complications in uremia.

Inpatient rehabilitation of patients requiring hemodialysis11No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the author(s) or upon any organization with which the author(s) is/are associated

OBJECTIVE

To evaluate the outcomes of patients who require hemodialysis and are admitted to an inpatient rehabilitation unit.

DESIGN

Retrospective review of the data of all admissions to an inpatient rehabilitation unit in 2001.

SETTING

University medical center.

PARTICIPANTS

All inpatient rehabilitation admissions in 2001 (N=531), including 497 patients who did not require hemodialysis and 34 who required hemodialysis.

INTERVENTION

A comprehensive rehabilitation program including physical therapy and occupational therapy. Speech and language therapy and rehabilitation psychology were provided when necessary.

MAIN OUTCOME MEASURES

Length of stay (LOS), change in total score on the FIM instrument, FIM efficiency, and place of discharge.

RESULTS

Admission and discharge FIM scores of the patients requiring hemodialysis were virtually identical to those of the other patients admitted to the unit. The average LOS of the hemodialysis patients was 5.4 days longer than that of the other patients, and, therefore, efficiency scores of the dialysis group were less than those of the other patients. The rate of discharge to the community did not differ significantly for the dialysis group.

CONCLUSIONS

Patients who require hemodialysis can benefit from rehabilitation services. Their improvement on the FIM instrument is comparable to that of other patients, but their LOS may be longer than that of other patients.