Nakamura Takeshi, Kamiya Kentaro, Hamazaki Nobuaki, Matsuzawa Ryota, Nozaki Kohei, Ichikawa Takafumi, Yamashita Masashi, Maekawa Emi, Reed Jennifer L, Noda Chiharu, Meguro Kentaro, Yamaoka-Tojo Minako, Matsunaga Atsuhiko, Ako Junya
Department of Rehabilitation Sciences, Kitasato University Graduate School of Medical Sciences, Sagamihara, Japan; Department of Rehabilitation, Juntendo University Hospital, Tokyo, Japan.
Department of Rehabilitation Sciences, Kitasato University Graduate School of Medical Sciences, Sagamihara, Japan; Department of Rehabilitation, School of Allied Health Sciences, Kitasato University, Sagamihara, Japan.
Can J Cardiol. 2021 Mar;37(3):476-483. doi: 10.1016/j.cjca.2020.06.019. Epub 2020 Jul 3.
This study was performed to test the hypothesis that low quadriceps isometric strength (QIS) is associated with greater risk of mortality and has the additive prognostic significance to the severity of heart failure (HF) and gait speed in older patients with HF.
A retrospective cohort study was performed in 1273 patients ≥ 60 years of age with HF (mean age 75 ± 8 years, 59.1% men); all of whom were evaluated during hospitalization for usual gait speed and maximal QIS. The QIS was expressed relative to body mass (% BM). The endpoint was all-cause mortality.
Over a median follow-up period of 1.59 years (interquartile range, 0.58 to 3.42 years), 224 patients died. The cutoff value based on the Youden index for the QIS discriminating those at high risk of mortality was 36.2% BM for overall, and we defined less than this cutoff point of QIS as low QIS. After adjustment for the HF risk score, the hazard ratio in low QIS was 1.55 for overall (95% confidence interval [CI], 1.17-2.06). The addition of low QIS to the HF risk score and gait speed was associated with significant increases in both net reclassification improvement (NRI, 0.239 for overall; 95% CI, 0.096-0.381) and integrated discrimination improvement (IDI, 0.004 for overall; 95% CI, 0.001-0.009) for all-cause mortality.
Low QIS was strongly associated with poor prognosis and showed complementary prognostic predictive capability to the HF risk score and gait speed in older patients with HF.
本研究旨在验证以下假设：股四头肌等长肌力（QIS）较低与较高的死亡风险相关，并且对老年心力衰竭（HF）患者的心力衰竭严重程度和步速具有额外的预后意义。
对1273例年龄≥60岁的HF患者进行了一项回顾性队列研究（平均年龄75±8岁，男性占59.1%）；所有患者均在住院期间接受了常规步速和最大QIS评估。QIS以相对于体重的百分比（%BM）表示。终点为全因死亡率。
在中位随访期1.59年（四分位间距，0.58至3.42年）内，224例患者死亡。基于约登指数确定的QIS区分高死亡风险患者的临界值总体为36.2%BM，我们将低于此QIS临界值定义为低QIS。在调整HF风险评分后，低QIS患者的总体风险比为1.55（95%置信区间[CI]，1.17 - 2.06）。将低QIS纳入HF风险评分和步速与全因死亡率的净重新分类改善（总体NRI为0.239；95%CI，0.096 - 0.381）和综合判别改善（总体IDI为0.004；95%CI，0.001 - 0.009）均显著增加相关。
低QIS与老年HF患者的不良预后密切相关，并且对HF风险评分和步速具有互补的预后预测能力。
