Staff Physician Nephrology Section, San Francisco VA Medical Center, San Francisco, CA.
J Ren Nutr. 2013 Sep;23(5):356-62. doi: 10.1053/j.jrn.2013.02.010. Epub 2013 May 3.
Although sarcopenia is thought to underlie the manifestations of frailty, association of frailty with measures of body composition is underinvestigated.
Eighty hemodialysis patients were included in the study. Performance-based frailty (PbF) used gait speed over 20 feet and 5 sit-to-stand (1 point each for lowest quintile) for the physical components of the frailty phenotype plus exhaustion (Short Form-36 [SF-36] vitality score <55) and physical activity (lowest quintile of weekly kcal energy expenditure on leisure activity on the Physical Activity Scale for the Elderly questionnaire; 1 point). Function-based frailty (FbF) defined by questionnaire measures of physical functioning (SF-36 Physical Function score <75; 1 point), exhaustion, and physical activity as for PbF. A score of 2 or greater was defined as frail. Outcomes related to muscle size included muscle area of the contractile tissue of the anterior tibialis and quadriceps muscles using magnetic resonance imaging, phase angle using bioimpedance analysis, lean body mass using dual energy X-ray absorptiometry, and body mass index (BMI). Linear regression was used to analyze associations between frailty and muscle size, with and without sex and age covariates.
Fifty-nine percent of individuals met PbF criteria, 63% met FbF criteria, and 55% met both. In univariate analysis, PbF and FbF were associated with smaller muscle area of the quadriceps, smaller phase angle, and higher BMI. Associations remained significant for the quadriceps after adjustment for age and sex. The magnitude of association of PbF with quadriceps muscle area was greater than 10 years of age (-30.3 cm(2)P = .02 vs. -6.6 cm(2)P < .0001) in multivariate analysis. There was no significant association between either measure of frailty and other measures of body composition after adjustment for age and sex.
Frailty was associated with measurements related to muscle size in a population of individuals with chronic kidney disease, a known contributor to muscle wasting.
虽然肌少症被认为是衰弱表现的基础,但衰弱与身体成分测量的关联仍未得到充分研究。
本研究纳入了 80 名血液透析患者。基于表现的衰弱(PbF)采用 20 英尺的步态速度和 5 次坐站(最低五分位数各 1 分)来评估衰弱表型的身体成分,外加疲劳(SF-36 活力评分<55)和身体活动(身体活动量表老年问卷中休闲活动每周千卡能量消耗的最低五分位数;1 分)。基于问卷测量的身体功能(SF-36 身体功能评分<75;1 分)、疲劳和身体活动定义的功能为基础的衰弱(FbF)与 PbF 相同。2 分或以上定义为衰弱。与肌肉大小相关的结局包括使用磁共振成像测量的前胫骨和股四头肌的收缩组织的肌肉面积、生物电阻抗分析的相位角、双能 X 射线吸收法测量的瘦体重和体重指数(BMI)。线性回归用于分析衰弱与肌肉大小之间的关系,包括有无性别和年龄协变量。
59%的个体符合 PbF 标准,63%符合 FbF 标准,55%符合两者标准。在单变量分析中,PbF 和 FbF 与股四头肌的肌肉面积较小、相位角较小和 BMI 较高有关。在调整年龄和性别后,与 FbF 相关的关联仍然显著。在多变量分析中,与年龄相关的关联强度大于 10 岁(-30.3cm2,P=0.02 与-6.6cm2,P<0.0001)。在调整年龄和性别后,两种衰弱测量方法与其他身体成分测量方法之间没有显著关联。
在患有慢性肾脏病的人群中,衰弱与与肌肉大小相关的测量指标相关,慢性肾脏病是肌肉消耗的已知原因。