Cupisti A, Capitanini A, Betti G, D'Alessandro C, Barsotti G
Division of Nephrology, Department of Internal Medicine, University of Pisa, Pisa, Italy.
Clin Nephrol. 2011 Mar;75(3):218-25. doi: 10.5414/cnp75218.
Assessment of physical activity level and of energy expenditure is important in the clinical and nutritional care of dialysis patients, but it is not so easy to accomplish. The SenseWear™ Armband (SWA) is a novel multisensory device that is worn on the upper arm and collects a variety of physiologic data related to physical activity. Thus, duration and intensity of physical activity is recorded and expressed as METs (Metabolic Equivalent Task), and energy expenditure is estimated. The aim of our study was to assess interdialytic spontaneous physical activity in stable chronic hemodialysis (HD) patients and the relation to nutritional status and dietary nutrient intake.
In 50 stable patients on maintenance hemodialysis treatment and 33 normal subjects (control group), level of spontaneous physical activity and estimated daily energy expenditure was assessed by SWA and related to biochemistry and anthropometry data, bioelectric impedance vector analysis, and energy and nutrient intake information coming from a 3-day food recall.
In respect to controls, HD patients showed lower mean daily METs value (1.3 ± 0.3 vs. 1.5 ± 0.2, p < 0.01), a lower time spent on activities > 3 METs (89 ± 85 vs. 143 ± 104 min/day, p < 0.05), lower number of steps per day (5,584 ± 3,734 vs. 11,735 ± 5,130, p < 0.001), resulting in a lower estimated energy expenditure (2,190 ± 629 vs. 2,462 ± 443 Kcal/day, p < 0.05). 31 out of the 50 HD patients (62%) had a mean daily value < 1.4 METs and hence were defined as sedentary. They differed from the active patients for higher age (63 ± 12 vs. 54 ± 12 y, p < 0.01), lower energy intake (26.1 ± 6.4 vs. 32.4 ± 11.3 Kcal/day, p < 0.05) and lower phase angle (5.5 ± 1.0 vs. 6.3 ± 0.9, p < 0.05). SWA-based estimation of daily energy expenditure was negatively related to age (r = -0.31, p < 0.05), whereas positive relations were observed with BMI (r = 0.51, p < 0.001), phase angle (r = 0.40, p < 0.01), serum phosphate (r = 0.49, p < 0.001) and albumin (r = 0.41, p < 0.01). The mean daily METs values were strongly related to normalized energy intake (r = 0.47, p < 0.001) and also to protein intake (r = 0.33, p < 0.05) and to phase angle (r = 0.38, p < 0.01). Multiple regression analysis showed that energy intake and dietary protein intake were independently related to the intensity of physical activity.
Our findings indicate that poor physical activity is highly prevalent in stable dialysis patients even when free from physical or neurological disabilities or severe comorbid conditions. The level and intensity of physical activity is positively related to body composition and to dietary nutrient intake. This confirms the strong interrelationship between exercise and nutrition, which in turn are associated with survival, rehabilitation and quality of life in dialysis patients.
评估身体活动水平和能量消耗在透析患者的临床及营养护理中至关重要，但实现起来并非易事。SenseWear™ 臂带（SWA）是一种新型多传感器设备，佩戴于上臂，可收集与身体活动相关的各种生理数据。由此，身体活动的持续时间和强度得以记录，并以代谢当量（METs）表示，同时估算能量消耗。我们研究的目的是评估稳定的慢性血液透析（HD）患者透析间期的自发身体活动情况，以及其与营养状况和膳食营养摄入的关系。
对50例接受维持性血液透析治疗的稳定患者和33名正常受试者（对照组），通过SWA评估自发身体活动水平和每日估算能量消耗，并将其与生化及人体测量数据、生物电阻抗矢量分析以及来自3天食物回顾的能量和营养摄入信息相关联。
与对照组相比，HD患者的平均每日METs值较低（1.3±0.3对1.5±0.2，p<0.01），进行>3METs活动的时间较少（89±85对143±104分钟/天，p<0.05），每日步数较少（5,584±3,734对11,735±5,130，p<0.001），导致估算的能量消耗较低（2,190±629对2,462±443千卡/天，p<0.05）。50例HD患者中有31例（62%）的平均每日值<1.4METs，因此被定义为久坐不动。他们与活跃患者的区别在于年龄较大（63±12对54±12岁，p<0.01）、能量摄入较低（26.1±6.4对32.4±11.3千卡/天，p<0.05）以及相位角较低（5.5±1.0对6.3±0.9，p<0.05）。基于SWA的每日能量消耗估算与年龄呈负相关（r = -0.31，p<0.05），而与体重指数（r = 0.51，p<0.001）、相位角（r = 0.40，p<0.01）、血清磷酸盐（r = 0.49，p<0.001）和白蛋白（r = 0.41，p<0.01）呈正相关。平均每日METs值与标准化能量摄入密切相关（r = 0.47，p<0.001），也与蛋白质摄入（r = 0.33，p<0.05）和相位角（r = 0.38，p<0.01）密切相关。多元回归分析表明，能量摄入和膳食蛋白质摄入与身体活动强度独立相关。
我们的研究结果表明，即使没有身体或神经功能障碍或严重合并症，稳定透析患者中身体活动不足的情况也非常普遍。身体活动的水平和强度与身体组成及膳食营养摄入呈正相关。这证实了运动与营养之间存在紧密的相互关系，而这又与透析患者的生存、康复及生活质量相关。
