The Shengli Clinical Medical College of Fujian Medical University, 134 Dongjie Road, Fuzhou, Fujian, 350100, People's Republic of China.
Department of Nursing, Fujian Provincial Hospital, Fuzhou, Fujian, People's Republic of China.
BMC Public Health. 2022 Jul 26;22(1):1414. doi: 10.1186/s12889-022-13842-1.
While physical inactivity or prolonged sitting has been linked to an increased risk of frailty, the interaction between sitting time (ST), physical activity (PA) and frailty is not well understood. The aim of this study was to examine the dose-response relationship between PA, ST and frailty and further to evaluate the interaction effect of PA and ST on frailty in the context of regular COVID-19 epidemic prevention and control in China.
A cross-sectional analysis was performed on 1458 participants (age ≥ 60) enrolled from a prospective cohort study of frailty in elderly people of Fujian Province. PA and ST levels were assessed using the International Physical Activity Questionnaire. A 40-item frailty index (FI) quantified frailty. Multivariable logistic regression and linear regression models were applied to examine the dose-response relationship between PA or ST and frailty level. Interaction plots were used to visualise the interaction effects of PA and ST on frailty.
Compared with light PA, the odds ratios (ORs) for frailty were significantly lower for moderate PA (OR, 0.609 [95% CI, 0.419, 0.885], P < .001) and vigorous PA (OR, 0.399 [95% CI, 0.236,0.673], P < .001). Comparing subjects with ST < 4 h/day, those with ST ≥ 8 h/day were significantly more likely to be diagnosed with frailty (OR, 3.140 [95% CI, 1.932, 5.106], P < .001), 6-8 h/day (OR, 1.289 [95% CI, 0.835, 1.989], P >0.05), and 4-6 h/day (OR, 1.400 [95% CI, 0.972, 2.018], P >0.05). Each one unit increase in metabolic equivalents (h/day) of PA was related to an average 0.928 (0.887, 0.971) decrease in prevalence of frailty, while each one unit increase in sitting time (h/day) was related to average 1.114 (1.046,1.185) increase in prevalence of frailty. Negative interactive effects of PA and ST on frailty were observed (P < 0.001).
There are nonlinear and linear dose-response relationships between PA, SB and frailty respectively. In addition, excess ST may counteract the beneficial effects of PA on frailty. Interventions that focus on reducing excess ST may be effective strategies to reduce the risk of frailty and should be taken seriously by public health authorities, especially in the context of regular epidemic prevention and control in China.
尽管身体活动不足或长时间久坐与虚弱风险增加有关，但坐的时间（ST）、身体活动（PA）和虚弱之间的相互作用尚不清楚。本研究的目的是检验 PA、ST 与虚弱之间的剂量-反应关系，并进一步评估 PA 和 ST 在我国常规 COVID-19 疫情防控背景下对虚弱的交互作用。
对来自福建省老年人虚弱前瞻性队列研究的 1458 名（年龄≥60 岁）参与者进行横断面分析。使用国际体力活动问卷评估 PA 和 ST 水平。使用 40 项虚弱指数（FI）量化虚弱。多变量逻辑回归和线性回归模型用于检验 PA 或 ST 与虚弱水平之间的剂量-反应关系。交互图用于直观显示 PA 和 ST 对虚弱的交互作用。
与轻度 PA 相比，中度 PA（OR，0.609 [95%CI，0.419，0.885]，P<0.001）和剧烈 PA（OR，0.399 [95%CI，0.236，0.673]，P<0.001）的虚弱发生比值比（OR）明显降低。与 ST<4 小时/天的受试者相比，ST≥8 小时/天的受试者更有可能被诊断为虚弱（OR，3.140 [95%CI，1.932，5.106]，P<0.001），6-8 小时/天（OR，1.289 [95%CI，0.835，1.989]，P>0.05），和 4-6 小时/天（OR，1.400 [95%CI，0.972，2.018]，P>0.05）。PA 每增加一个代谢当量（h/天），虚弱的患病率平均降低 0.928（0.887，0.971），而 ST 每增加一个单位（h/天），虚弱的患病率平均增加 1.114（1.046，1.185）。PA 和 ST 对虚弱的负交互作用是观察到的（P<0.001）。
PA、SB 与虚弱之间分别存在非线性和线性剂量-反应关系。此外，过度的 ST 可能会抵消 PA 对虚弱的有益影响。关注减少过度 ST 的干预措施可能是降低虚弱风险的有效策略，应引起公共卫生当局的重视，尤其是在中国常规疫情防控背景下。
