Utility of the low physical activity questionnaire for hemodialysis patients with frailty: a cross-sectional study

Abstract Background The low physical activity questionnaire (LoPAQ), which has been developed to assess the low levels of physical activity in patients on dialysis, is so far available only in English. Moreover, no study has examined whether the LoPAQ can be used to screen for frailty in patients on hemodialysis. The purpose of this study was to translate the original LoPAQ into Japanese and evaluate its utility in screening for frailty among patients on hemodialysis. Methods For this cross-sectional study, we enrolled patients from two hemodialysis facilities in Japan between April 2018 and June 2019. We used the LoPAQ to calculate physical activity for one week, with pedometer steps (steps/week) as the standard reference. We used Spearman’s rank test and two multiple linear regression models to assess the relationship between the Japanese LoPAQ results and pedometer step counts. Finally, we examined whether the LoPAQ had the ability to screen for frailty (Fried scale ≥ 3) using area under the curves. Results In total, 220 patients on hemodialysis completed the LoPAQ and wore a pedometer for one week. Their mean age was 67.8 ± 11.6 years, and 59.1% were men. The LoPAQ showed a total physical activity of 825.0 kilocalories/week and walking activity of 315.0 kilocalories/week. The LoPAQ total physical activity and walking activity were significantly correlated with pedometer step counts (r = 0.37–0.53, P < 0.01). Furthermore, LoPAQ total physical activity and walking activity were associated with pedometer step counts despite adjusting for covariates (β: 3.33–5.45, P < 0.001, β: 8.63–16.80, P < 0.001, respectively). In addition, the LoPAQ total physical activity and walking activity showed good values in the area under the curves to identify frailty (0.72 and 0.73, respectively). Conclusions Physical activity assessed using the LoPAQ significantly correlated with pedometer step counts in Japanese patients on hemodialysis. Furthermore, the LoPAQ total physical activity and walking activity had a moderate screening ability for frailty. The results indicate that the LoPAQ questionnaire is useful as a physical activity assessment tool and as a screening tool for frailty in patients on hemodialysis

Simplified discriminant parameters for sarcopenia among patients undergoing haemodialysis

Abstract Background Patients with end‐stage renal disease (ESRD) are at an increased risk of developing sarcopenia, which can lead to various adverse health outcomes. Although the diagnosis of sarcopenia is essential for clinical management, it is not feasible in routine clinical practice for populations undergoing haemodialysis because it is time‐consuming and resources are limited. Serum creatinine levels in patients with ESRD have been gaining attention as a screening parameter for sarcopenia because serum creatinine is a routinely measured byproduct of skeletal muscle metabolism. This study aimed to evaluate the discriminative ability of the creatinine‐derived index for sarcopenia in patients undergoing haemodialysis. Methods We diagnosed sarcopenia according to the Asian Working Group for Sarcopenia (AWGS) 2 criteria in 356 clinically stable outpatients with ESRD enrolled from three dialysis facilities. We adopted the modified creatinine index as a simplified discriminant parameter for sarcopenia in addition to the calf circumference, SARC‐F score, and combination of both (i.e. SARC‐CalF score), which are recommended by the AWGS. Receiver operating characteristic analysis and logistic regression analysis were conducted to evaluate the discriminative ability of the modified creatinine index for sarcopenia. Results Of the study participants, 142 (39.9%) were diagnosed with sarcopenia. The areas under the curve of the modified creatinine index against sarcopenia in the male and female participants were 0.77 (95% confidence interval [CI]: 0.71 to 0.83) and 0.77 (95% CI: 0.69 to 0.85), respectively. All simplified discriminant parameters were significantly associated with sarcopenia, even after adjusting for patient characteristics and centre. In the comparison of the odds ratios for sarcopenia for 1‐standard deviation change in the simplified discriminant parameters, the odds ratio of the modified creatinine index was 1.92 (95% CI: 1.15 to 3.19), which was lower than that of the calf circumference (odds ratio: 6.58, 95% CI: 3.32 to 13.0) and similar to that of the SARC‐F (odds ratio: 1.57, 95% CI: 1.14 to 2.16) and SARC‐CalF scores (odds ratio: 2.36, 95% CI: 1.60 to 3.47). Conclusions This study revealed a strong association between the creatinine‐derived index and sarcopenia in patients undergoing haemodialysis. The modified creatinine index was equal or superior to those of SARC‐F and SARC‐CalF score in discriminability for sarcopenia. However, the ability of the calf circumference to discriminate sarcopenia is extremely high, and further study is needed to determine whether it can be used to detect deterioration of muscle mass and function over time