Faculty of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa-city, Saitama, 359-1192, Japan.
National Institute of Health and Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition, 17-34 Senrioka-Shimmachi, Settsu-city, Osaka, 566-0002, Japan.
Int J Behav Nutr Phys Act. 2023 Dec 25;20(1):150. doi: 10.1186/s12966-023-01550-x.
Physical activity or biomarker-calibrated energy intake (EI) alone is associated with mortality in older adults; the interaction relationship between the combined use of both factors and mortality has not been examined. We evaluated the relationship between mortality and calibrated EI and step counts in older adults.
This prospective study included 4,159 adults aged ≥65 years who participated in the Kyoto-Kameoka study in Japan and wore a triaxial accelerometer between 1 April and 15 November 2013. The calibrated EI was calculated based on a previously developed equation using EI biomarkers. The step count was obtained from the accelerometer ≥ 4 days. Participants were classified into the following four groups: low EI (LEI)/low step counts (LSC) group (EI: <2,400 kcal/day in men and <1,900 kcal/day in women; steps: <5,000 /day), n = 1,352; high EI (HEI)/LSC group (EI: ≥2,400 kcal/day in men and ≥1,900 kcal/day in women; steps: <5,000 /day), n = 1,586; LEI/high step counts (HSC) group (EI: <2,400 kcal/day in men and < 1,900 kcal/day in women; steps: ≥5,000 /day), n = 471; and HEI/HSC group (EI: ≥2,400 kcal/day in men and ≥1,900 kcal/day in women; steps: ≥5,000 /day), n = 750. Mortality-related data were collected until 30 November 2016. We performed a multivariable Cox proportional hazard analysis.
The median follow-up period was 3.38 years (14,046 person-years), and 111 mortalities were recorded. After adjusting for confounders, the HEI/HSC group had the lowest all-cause mortality rate compared to other groups (LEI/LSC: reference; HEI/LSC: hazard ratio [HR]: 0.71, 95% confidence interval [CI]: 0.41-1.23; LEI/HSC: HR: 0.59, 95% CI: 0.29-1.19; and HEI/HSC: HR: 0.10, 95% CI: 0.01-0.76). No significant interaction was observed between the calibrated EI and steps with mortality. The spline model showed that 35-42 kcal/100 steps/day of EI/100 steps was associated with the lowest mortality risk.
HR mortality risk was lowest at 35-42 kcal/100 steps/day, suggesting that very high (≥56 kcal) or low (<28 kcal) EI/100 steps are not inversely associated with mortality. Adherence to optimal EI and adequate physical activity may provide sufficient energy balance to explain the inverse association with mortality among older Japanese adults.
体力活动或生物标志物校准的能量摄入（EI）单独与老年人的死亡率有关；两者联合使用与死亡率的交互关系尚未被研究。我们评估了死亡率与校准的 EI 和步数在老年人中的关系。
这项前瞻性研究包括 4159 名年龄≥65 岁的成年人，他们在日本的京都-龟冈研究中佩戴三轴加速度计，时间为 2013 年 4 月 1 日至 11 月 15 日。EI 是根据之前开发的使用 EI 生物标志物的方程计算得出的。步数是从加速度计中获得的，要求参与者≥4 天佩戴。参与者被分为以下四组：低 EI（LEI）/低步数（LSC）组（EI：男性<2400 kcal/天，女性<1900 kcal/天；步数：<5000 步/天），n=1352；高 EI（HEI）/LSC 组（EI：男性≥2400 kcal/天，女性≥1900 kcal/天；步数：<5000 步/天），n=1586；LEI/高步数（HSC）组（EI：男性<2400 kcal/天，女性<1900 kcal/天；步数：≥5000 步/天），n=471；HEI/HSC 组（EI：男性≥2400 kcal/天，女性≥1900 kcal/天；步数：≥5000 步/天），n=750。直到 2016 年 11 月 30 日收集与死亡率相关的数据。我们进行了多变量 Cox 比例风险分析。
中位随访时间为 3.38 年（14046 人年），记录了 111 例死亡。在调整混杂因素后，与其他组相比，HEI/HSC 组的全因死亡率最低（LEI/LSC：参考；HEI/LSC：风险比[HR]：0.71，95%置信区间[CI]：0.41-1.23；LEI/HSC：HR：0.59，95% CI：0.29-1.19；和 HEI/HSC：HR：0.10，95% CI：0.01-0.76）。未观察到校准的 EI 和步数与死亡率之间存在显著的交互作用。样条模型显示，EI/100 步 35-42 kcal 与最低的死亡率风险相关。
EI/100 步 35-42 kcal 的 HR 死亡率风险最低，这表明非常高（≥56 kcal）或低（<28 kcal）EI/100 步与死亡率没有负相关。坚持最佳 EI 和足够的体力活动可能会提供足够的能量平衡，从而解释日本老年人死亡率呈负相关的原因。
