Physical Exercise Improves Cognitive Function in Older Adults with Stage 3-4 Chronic Kidney Disease: A Randomized Controlled Trial.

INTRODUCTION: Patients with chronic kidney disease (CKD) exhibit a higher probability of having cognitive impairment or dementia than those without CKD. The beneficial effects of physical exercise on cognitive function are known in the general older population, but more research is required in older adults with CKD. METHODS: Eighty-one outpatients (aged ≥65 years) with CKD stage G3-G4 were assessed for eligibility. Among them, 60 were randomized (single-center, unblinded, and stratified) and 53 received the allocated intervention (exercise n = 27, control n = 26). Patients in the exercise group undertook group-exercise training at our facility once weekly and independent exercises at home twice weekly or more, for 24 weeks. Patients in the control group received general care. General and specific cognitive functions (memory, attention, executive, and verbal) were measured, and differences in their scores at baseline and at the 24-week follow-up visit were assessed between the 2 groups. RESULTS: Forty-four patients completed the follow-up at 24 weeks (exercise n = 23, control n = 21). Patients in the exercise group showed significantly greater changes in Wechsler Memory Scale-Revised Logical Memory delayed recall (exercise effect: 2.82, 95% CI: 0.46-5.19, p = 0.03), and immediate and delayed recall (exercise effect: 5.97, 95% CI: 1.13-10.81, p = 0.02) scores than those in the control group. CONCLUSIONS: The 24-week exercise intervention significantly improved the memory function in older adults with pre-dialysis CKD. This randomized controlled trial suggests that physical exercise is a useful nonpharmacological strategy for preventing cognitive decline in these patients.

Effects of resistance training using elastic bands on muscle strength with or without a leucine supplement for 48 weeks in elderly patients with type 2 diabetes.

Type 2 diabetes is associated with sarcopenia. Resistance training and appropriate nutritional therapy are reported to be effective for muscle strength and mass. This study aimed to evaluate the effect of resistance training using elastic bands at home combined with a leucine-rich amino acid supplement on muscle strength, physical function, and muscle mass in elderly type 2 diabetes. We conducted a 48-week prospective single-center randomized controlled trial in 60 patients who were randomly allocated to one of three groups: control (C), resistance exercise (R), and resistance exercise plus supplement (RL). R and RL groups performed daily bodyweight resistance training with elastic bands exercises at home, and the RL group also took 6 g of a leucine-rich amino acid supplement daily. Knee extension strength (muscle strength), grip strength, usual gait speed (physical function), muscle mass, and cognitive function were assessed at 0 and 48 weeks. Although the change in knee extension strength from baseline was significantly increased by 6.4 Nm (95% CI 1.0, 11.7) in the RL group (p = 0.036), no significant difference was observed among the three groups (p = 0.090). Physical function, muscle mass, and cognitive function also had no changes during the study period among the three groups. No additive effect of a leucine-rich amino acid supplement on muscle strength or mass was observed. Although a post hoc analysis comparing with or without resistance training (C group vs. R + RL group) found that knee extension strength was significantly increased (p = 0.028), and cognitive decline was less (p = 0.046) than in the C group.

The impact of the combination of kidney and physical function on cognitive decline over 2 years in older adults with pre-dialysis chronic kidney disease.

BACKGROUND: No longitudinal study has investigated the impact of combination of kidney function (KF) and physical function (PF) on cognitive decline in these patients. METHODS: We conducted a 2-year prospective cohort study enrolling 131 patients ≥ 65 years with pre-dialysis chronic kidney disease (CKD). We assessed cognitive function with the Japanese version of the Montreal Cognitive Assessment (MoCA-J). We calculated %MoCA-J based on the rate of change between baseline and follow-up MoCA-J scores, and defined cognitive decline over 2 years as a %MoCA-J of less than the first quartile value. We defined eGFR ≥ 30 as mild-to-moderate and eGFR < 30 mL/min per 1.73 m2 as severe. In addition, low PF was defined as low handgrip strength (< 26 for men and < 18 kgf for women) and/or low gait speed (< 0.8 m/s). Patients were classified into four groups: group 1, patients with mild-to-moderate impairment in KF and high PF; group 2, with mild-to-moderate impairment in KF and low PF; group 3, with severe impairment in KF and high PF; and group 4, with severe impairment in KF and low PF. RESULTS: Eighty-four patients completed follow-up assessment. Multivariate logistic regression analysis showed that the combination of severe impairment in KF and low PF was significantly associated with cognitive decline (odds ratio 5.73). However, no significant cognitive decline was observed in patients with either severe impairment in KF or low PF alone. CONCLUSIONS: We may need to focus on maintaining PF in older patients with advanced CKD may help to prevent cognitive decline.

Mild cognitive impairment in older adults with pre-dialysis patients with chronic kidney disease: Prevalence and association with physical function.

AIM: Chronic kidney disease (CKD) is a risk factor for declining cognitive and physical function. However, the prevalence of mild cognitive impairment (MCI) and its relationship with physical function is not clear. Therefore, our aim was to evaluate the prevalence of MCI and the relationship between MCI and physical function among older adults with pre-dialysis CKD. METHODS: We conducted a cross-sectional study of 120 patients, aged ≥65 years (mean age, 77.3 years), with pre-dialysis CKD but without probable dementia (Mini Mental State Examination <24). MCI was evaluated using the Japanese version of the Montreal Cognitive Assessment (MoCA-J). For analysis, patients were classified into two cognitive function groups: normal (MoCA-J ≥ 26) and MCI (MoCA-J < 26). Physical, clinical, and biochemical parameters were compared between the groups. Logistic and linear regression analyses were used to evaluate the specific association between cognitive and physical function. RESULTS: Seventy-five (62.5%) patients belonged to the MCI group. Significant differences between the two groups were identified for gait speed, balance, age, and haemoglobin concentration. After adjustment for covariates, only gait speed was significantly associated with MCI (odds ratio, 0.06; 95% confidence interval, 0.009-0,411). CONCLUSION: The prevalence of MCI among older adults with pre-dialysis CKD was as high as 62.5%. The association between MCI and reduced gait speed supports the possible interaction between physical and cognitive functions and the need for early screening.

Effects of home-based exercise on pre-dialysis chronic kidney disease patients: a randomized pilot and feasibility trial.

BACKGROUND: Only a few research is available on the effects of home-based exercise training on pre-dialysis chronic kidney disease (CKD) patients. Therefore, we aimed to elucidate the effect of home-based exercise therapy on kidney function and arm and leg muscle strength in pre-dialysis CKD patients. METHODS: Thirty-six male stage 3-4 pre-dialysis CKD patients (age, 68.7 ± 6.8 years; estimated glomerular filtration rate (eGFR), 39.0 ± 11.6 ml/min/1.73 m2) who were being treated as outpatients were included. The subjects were randomly assigned to an exercise intervention group (Ex group: 18) and a control group (C group: 18). The Ex group wore accelerometer pedometers and were instructed to perform home-based aerobic and resistance exercises, such as brisk walking for 30 min per day, for 12 months. The C group subjects wore accelerometer pedometers but received no exercise therapy guidance; the number of steps covered during normal daily activities was recorded for the C group. The outcome measures were changes in kidney function and handgrip and knee extension muscle strength. Values at the baseline (T1) and 12 months later (T2) were compared. RESULTS: There were no significant differences in baseline characteristics between the two groups; however, the C group was more physically active than the Ex group. Eight subjects dropped out, and 28 subjects (14 in each group) were included in the final analysis. Physical activity increased significantly only in the Ex group. Grip strength (F = 7.0, p = 0.01) and knee extension muscle strength (F = 14.3, p < 0.01) were found to improve only in the Ex group. Further, the changes in eGFR were not significantly different between the two groups (F = 0.01, p = 0.93). CONCLUSIONS: Home-based exercise therapy for pre-dialysis CKD patients was feasible and improved arm and leg muscle strength without affecting kidney function. TRIAL REGISTRATION: UMIN Clinical Trials Registry ( UMIN000005091 ). Registered 2/15/2011.

Respiratory muscle strength in relation to sarcopenia in elderly cardiac patients.

BACKGROUND AND AIMS: Little information exists on the relation between respiratory muscle strength such as maximum inspiratory muscle pressure (MIP) and sarcopenia in elderly cardiac patients. The present study aimed to determine the differences in MIP, and cutoff values for MIP according to sarcopenia in elderly cardiac patients. METHODS: We enrolled 63 consecutive elderly male patients aged ≥65 years with cardiac disease in this cross-sectional study. Sarcopenia was defined based on the European Working Group on Sarcopenia in Older People algorithm, and, accordingly, the patients were divided into two groups: the sarcopenia group (n = 24) and non-sarcopenia group (n = 39). The prevalence of sarcopenia in cardiac patients and MIP in the patients with and without sarcopenia were assessed to determine cutoff values of MIP. RESULTS: After adjustment for body mass index, the MIP in the sarcopenia group was significantly lower than that in the non-sarcopenia group (54.7 ± 36.8 cmH2O; 95 % CI 42.5-72.6 vs. 80.7 ± 34.7 cmH2O; 95 % CI 69.5-92.0; F = 4.89, p = 0.029). A receiver-operating characteristic curve analysis of patients with and without sarcopenia identified a cutoff value for MIP of 55.6 cmH2O, with a sensitivity of 0.76, 1-specificity of 0.37, and AUC of 0.70 (95 % CI 0.56-0.83; p = 0.01) in the study patients. CONCLUSION: Compared with elderly cardiac patients without sarcopenia, MIP in those with sarcopenia may be negatively affected. The MIP cutoff value reported here may be a useful minimum target value for identifying elderly male cardiac patients with sarcopenia.

Knee extensor muscle strength and index of renal function associated with an exercise capacity of 5 metabolic equivalents in male chronic heart failure patients with chronic kidney disease.

BACKGROUND: The goal of the present study was to determine knee extensor muscle strength (KEMS) and degree of renal dysfunction associated with an exercise capacity of ≥5 metabolic equivalents (METs) in male chronic heart failure (CHF) patients with chronic kidney disease (CKD). METHODS: In this cross-sectional study of 75 male CHF patients with CKD (65.3 ± 11.6 years), we measured clinical characteristics, peak [Formula: see text], estimated glomerular filtration rate (eGFR), and KEMS. Patients were divided into two groups by exercise capacity: ≥5 METs group (n = 41) and <5 METs group (n = 34). Cutoff values for KEMS and eGFR resulting in an exercise capacity of ≥5 METs were selected with ROC curves. Patients were divided into four groups according to cutoff values, and numbers of patients attaining an exercise capacity of ≥5 METs were compared between groups. RESULTS: Age was significantly higher although eGFR, Hb, and KEMS were lower in the <5 METs versus ≥5 METs group (P < 0.001). Multiple logistic regression analysis revealed a positive significant relation between KEMS and eGFR and exercise capacity of ≥5 METs. Exercise capacity of ≥5 METs was associated with KEMS of approximately 1.69 Nm/kg and an eGFR of 45.7 mL/min/1.73 m(2). The number of patients attaining an exercise capacity of ≥5 METs in the patients who did not reach both cutoff values was significantly lower than that in any other patients (P < 0.001). CONCLUSION: KEMS and eGFR may be useful indices for predicting attainment of exercise capacity of ≥5 METs in male CHF patients with CKD.

Decreased physical function in pre-dialysis patients with chronic kidney disease.

BACKGROUND: Patients undergoing dialysis experience decreases in physical function; however, few data exist on physical function in pre-dialysis patients with chronic kidney disease (CKD). The primary objective of this study was to clarify physical function in pre-dialysis patients according to CKD stage. METHODS: This was a cross-sectional study of 120 ambulant pre-dialysis CKD stage 2 or higher patients (85 male, 35 female; mean age 66.5 years) who visited St. Marianna University School of Medicine Hospital. Participants were grouped according to CKD stage as follows: stage 2 (n = 17), stage 3 (n = 55), stage 4 (n = 25), and stage 5 (n = 23). Handgrip strength, knee extensor muscle strength, single-leg stance time, and maximum gait speed were used to assess physical function. Clinical laboratory tests were also examined at the same time as physical function measurements. RESULTS: All indices of physical function decreased according to the progression of CKD. Each physical function index was significantly lower in CKD stage 4 or 5 patients than CKD stage 2 or 3 patients. All physical function indices showed a positive correlation with estimated glomerular filtration rate (eGFR), blood hemoglobin level, and serum albumin level, and a negative correlation with urinary protein levels. In multiple regression analysis, age, female sex, body mass index, eGFR and urinary protein were significantly correlated with indices of physical function. CONCLUSION: Physical function in pre-dialysis CKD patients decreased as the disease progressed according to stage. Early intervention in CKD patients might delay the loss of physical function.

Moderate-intensity single exercise session does not induce renal damage.

BACKGROUND: The aim of this study was to determine whether a single moderate-intensity exercise session induces renal injury based on various parameters that reflect kidney dysfunction, including urinary L-type fatty acid-binding protein (L-FABP). METHODS: Adult outpatients (n = 31) with chronic kidney disease (CKD) not receiving renal replacement therapy participated in this study. Urine was collected before and after a single 20-min moderate-intensity exercise session. Urinary levels of L-FABP, albumin, N-acetyl-ß-d-glucosaminidase (NAG), and α1-microglobrin (α1MG) were measured. In addition, 12 patients with estimated glomerular filtration fraction less than 30 ml/min/1.73 ml(2) were selected from all patients and evaluated using the same analysis. RESULTS: Urinary values of L-FABP, albumin, NAG, and α1MG did not increase significantly after exercise compared with before exercise (urinary L-FABP, from 8.3 to 9.4 µg/g of creatinine; urinary albumin, from 293.1 to 333.7 mg/g of creatinine; urinary NAG, from 9.2 to 8.2 U/g of creatinine; urinary α1MG, from 11.4 to 9.8 mg/g of creatinine, not significant). Similar findings were seen in all patients, regardless of degree of renal dysfunction. CONCLUSIONS: A single session of moderate-intensity exercise was not associated with an increase in renal parameters used to assess renal damage.

Determination of the effectiveness of accelerometer use in the promotion of physical activity in cardiac patients: a randomized controlled trial.

OBJECTIVE: To investigate the effect of the self-monitoring of physical activity by hospitalized cardiac patients attending phase I cardiac rehabilitation (CR). DESIGN: Randomized controlled trial. SETTING: University hospital CR program. PARTICIPANTS: CR patients (N=126) with a mean age of 59.1 years. INTERVENTIONS: Patients were randomly assigned to the self-monitoring group (group A, n=63) or the control group (group B, n=63). Along with CR, group A patients performed self-monitoring of their physical activity at the beginning of a phase I CR program (acute in-hospital phase for inpatients) and ending just before they began a phase II CR program (postdischarge recovery phase for outpatients). MAIN OUTCOME MEASURES: Physical activity (averages of daily number of steps taken and daily energy expenditure for 1wk) as measured by accelerometer was assessed in both groups at baseline (t1) and before the beginning of phase II CR (t2). RESULTS: Although there were no significant differences in physical activity values between groups A and B at t1, values of group A at t2 were significantly higher than those of group B (8609.6 vs 5512.9 steps, P<.001; 242.6 vs 155.9kcal, P<.001). CONCLUSIONS: Self-monitoring of patient physical activity from phase I CR might effectively increase the physical activity level in preparation for entering a phase II CR program. Results of the present study could contribute to the development of new strategies for the promotion of physical activity in cardiac patients.

Physical activity is associated with serum albumin in peritoneal dialysis patients.

The incidence of metabolic syndrome is about 50% in peritoneal dialysis (PD) patients. The positive association of metabolic syndrome with lower physical activity (PA) has been reported in the general population, but the effect of PA in PD patients has not been clarified. The purpose of the present study was to evaluate PA in PD patients and to clarify the correlations between PA and various clinical parameters in PD patients. We assessed 38 PD patients (22 men; age: 63.9 +/- 10.8 years; body mass index: 24.0 +/- 3.9; 15 with diabetes) who had been treated with PD at least for 3 months. We defined PA as the average number of steps per day measured using a pedometer for 1 month. Blood biochemical findings and dialysis adequacy were measured as clinical parameters. Of the 38 patients, only 11 (29%) reached the steps per day of healthy individuals. In addition, steps per day were significantly correlated with serum albumin (r = 0.45, p = 0.01), C-reactive protein (r = -0.33, p = 0.04), and age (r = -0.34, p = 0.04). Multiple regression analysis showed that serum albumin was the only variable that significantly correlated with steps per day (beta = 0.42, p = 0.01). Our study showed that PA declines significantly in PD patients, which might correlate with malnutrition-inflammation-atherosclerosis syndrome.

Relationship between Serum Vitamin D and Leg Strength in Older Adults with Pre-Dialysis Chronic Kidney Disease: A Preliminary Study.

Active vitamin D (calcitriol, or 1.25 (OH) 2 D) is associated with muscle weakness, falls, and fracture in community-dwelling older people. This study aimed to investigate the relationship between a serum active vitamin D level and lower extremity muscle strength in elderly patients with pre-dialysis chronic kidney disease (CKD). This cross-sectional study included 231 patients with CKD treated conservatively as outpatients. We analyzed patient background factors, including age, sex, body mass index (BMI), intact parathyroid hormone (PTH), phosphorus, calcium, albumin, serum calcitriol level as an indicator of active vitamin D, and estimated glomerular filtration rate (eGFR) collected from medical records. As an index of lower extremity muscle strength, the isometric knee extension muscle strength-to-weight ratio (kgf/kg) was calculated. The mean patient age was 75.9 ± 6.1 years (68.8% male), and the BMI was 24.1 ± 3.8 kg/m2. A significant correlation was observed between knee extensor muscle strength and serum calcitriol level (r = 0.32, p < 0.01), age (r = -0.30, p < 0.01), BMI (r = -0.31, p < 0.01), intact PTH (r = -0.22, p < 0.01), phosphorus (r = -0.29, p < 0.01), albumin (r = -0.28, p < 0.01), and eGFR (r = 0.25, p < 0.01). Multiple regression analysis showed calcitriol to be significantly associated with knee extensor muscle strength (ß: 0.14, 95% confidence interval: 0-0.002, p = 0.04) after adjustment for covariates. These results suggest that the serum active vitamin D level is associated with lower extremity muscle strength in older adults with pre-dialysis CKD. It is necessary to verify whether vitamin D supplementation increases lower extremity muscle strength in pre-dialysis CKD patients.

Handgrip strength as a predictor of prognosis in Japanese patients with congestive heart failure.

BACKGROUND: Whether upper-extremity and lower-extremity muscle strength can predict a prognosis of congestive heart failure (CHF) patients is unclear. This study evaluated the impact of muscle strength on long-term mortality in patients with CHF. DESIGN: Prospective observational study of male Japanese CHF patients. METHODS: Clinical characteristics (age, body mass index, left ventricular ejection fraction, heart failure etiology, and medications) were obtained from hospital records of 148 male outpatients with stable CHF. Brain natriuretic peptide was determined as an index of disease severity. Peak oxygen uptake ((Equation is included in full-text article.)), handgrip, and knee extensor muscle strength were also determined. RESULTS: After 1331.9+/-700.3 days of follow-up, 13 cardiovascular-related deaths occurred, and the patients were divided into two groups: survival (n=135) and nonsurvival (n=13). No significant differences were found between the groups in clinical characteristics, brain natriuretic peptide levels, and knee extensor muscle strength. Peak(Equation is included in full-text article.)(P=0.011) and handgrip strength (P=0.008) were significantly lower in the nonsurvival versus survival group. Left ventricular ejection fraction, peak(Equation is included in full-text article.), and handgrip strength were found by univariate Cox proportional hazards analysis to be significant prognostic indexes of survival. Multivariate analysis, however, revealed handgrip strength to be an independent predictor of prognosis. A handgrip strength cutoff value of 32.2 kgf was determined by the analysis of receiver-operating characteristics and was assessed. Kaplan-Meier survival curves after log-rank test showed significant prognostic difference between the two groups (P=0.008). CONCLUSION: Handgrip strength may be useful for forecasting prognosis in patients with CHF.

Longitudinal Changes of Handgrip, Knee Extensor Muscle Strength, and the Disability of the Arm, Shoulder and Hand Score in Cardiac Patients During Phase II Cardiac Rehabilitation.

Handgrip strength (HS) and knee extensor muscle strength (KEMS) showed a negative correlation with the Disabilities of the Arm, Shoulder, and Hand (DASH) score at one month following cardiac surgery. We performed a longitudinal study to examine changes in HS/KEMS and DASH score during phase II cardiac rehabilitation (CR) in patients after cardiac surgery. We measured and assessed HS, KEMS, and DASH score in 41 consecutive patients at one and three months following cardiac surgery and examined the relation between these factors at three months following cardiac surgery. Wilcoxon signed-rank test and Spearman correlation coefficients were used to analyze the results. Finally, 26 patients (63.2 years, 73.1% male) were analyzed. There were significant differences from one month to three months following cardiac surgery in HS (26.78 ± 8.26 to 31.35 ± 9.41 kgf, p < 0.001), KEMS (1.53 ± 0.42 to 1.72 ± 0.46 Nm/kg, p = 0.001), and DASH score (14.76 ± 12.58 to 7.62 ± 9.29, p < 0.001). DASH score correlated negatively with HS (r = -0.41, p = 0.01) but not with KEMS (r = -0.32, p = 0.09) after three months of phase II CR. Although HS, KEMS, and DASH scores changed significantly from one to three months following cardiac surgery during phase II CR, only HS correlated negatively with DASH score at three months following cardiac surgery.

Gender-related differences in clinical characteristics and physiological and psychosocial outcomes of Japanese patients at entry into phase II cardiac rehabilitation.

OBJECTIVE: To examine gender differences in clinical characteristics and physiological and psychosocial outcomes at entry into phase II cardiac rehabilitation. DESIGN: Cross-sectional study. SUBJECTS: The study comprised 442 consecutive patients with cardiac diseases assessed at entry into a phase II cardiac rehabilitation programme. METHODS: Clinical characteristics of the patients, such as age, education, marital status, employment and body mass index, were obtained from hospital records. Oxygen uptake, handgrip and knee extensor muscle strength were measured to assess physiological outcomes. Self-efficacy for physical activity, hospital anxiety depression scale and health-related quality of life assessed by Short Form-36 were evaluated to assess psychosocial outcomes. RESULTS: The number of married women and their levels of education, employment and body mass index were significantly lower, and their ages higher, than those of the men. Measures of physiological outcome in women were significantly lower than those in men. Measures of self-efficacy for physical activity and Short Form-36 physical and emotional subscale scores were lower and anxiety levels higher in women than in men. CONCLUSION: Cardiac rehabilitation programmes exclusively for women focusing on physiological outcomes, group counselling, and training to enhance physical and emotional domains may encourage increased participation by women in cardiac rehabilitation.