Kankaanpää Anna, Tolvanen Asko, Joensuu Laura, Waller Katja, Heikkinen Aino, Kaprio Jaakko, Ollikainen Miina, Sillanpää Elina
Gerontology Research Center (GEREC), Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland.
Methodology Center for Human Sciences, University of Jyväskylä, Jyväskylä, Finland.
medRxiv. 2023 Jun 5:2023.06.02.23290916. doi: 10.1101/2023.06.02.23290916.
The association between leisure-time physical activity (LTPA) and a lower risk of mortality is susceptible to bias from multiple sources. We investigated the potential of biological ageing to mediate the association between long-term LTPA and mortality and whether the methods used to account for reverse causality affect the interpretation of this association.
Study participants were twins from the older Finnish Twin Cohort (=22,750; 18-50 years at baseline). LTPA was assessed using questionnaires in 1975, 1981 and 1990. The mortality follow-up lasted until 2020 and biological ageing was assessed using epigenetic clocks in a subsample (=1,153) with blood samples taken during the follow-up. Using latent profile analysis, we identified classes with distinct longitudinal LTPA patterns and studied differences in biological ageing between these classes. We employed survival models to examine differences in total, short-term and long-term all-cause mortality, and multilevel models for twin data to control for familial factors.
We identified four classes of long-term LTPA: sedentary, moderately active, active and highly active. Although biological ageing was accelerated in sedentary and highly active classes, after adjusting for other lifestyle-related factors, the associations mainly attenuated. Physically active classes had a maximum 7% lower risk of total mortality over the sedentary class, but this association was consistent only in the short term and could largely be accounted for by familial factors. LTPA exhibited less favourable associations when prevalent diseases were exclusion criteria rather than covariate.
Being active may reflect a healthy phenotype instead of causally reducing mortality.
休闲时间身体活动（LTPA）与较低的死亡风险之间的关联容易受到多种来源的偏倚影响。我们研究了生物衰老在长期LTPA与死亡率之间的关联中所起的中介作用，以及用于解释反向因果关系的方法是否会影响对这种关联的解读。
研究参与者为芬兰老年双胞胎队列中的双胞胎（n = 22,750；基线年龄18 - 50岁）。在1975年、1981年和1990年通过问卷调查评估LTPA。死亡率随访持续至2020年，在随访期间采集血样的一个子样本（n = 1,153）中，使用表观遗传时钟评估生物衰老。通过潜在剖面分析，我们识别出具有不同纵向LTPA模式的类别，并研究这些类别之间生物衰老的差异。我们采用生存模型来检验总全因死亡率、短期和长期全因死亡率的差异，并使用双胞胎数据的多水平模型来控制家族因素。
我们识别出四类长期LTPA：久坐不动型、中度活跃型、活跃型和高度活跃型。尽管久坐不动型和高度活跃型的生物衰老加速，但在调整其他与生活方式相关的因素后，这些关联主要减弱。与久坐不动型相比，身体活跃型的总死亡率最高降低7%，但这种关联仅在短期内一致，并且在很大程度上可由家族因素解释。当将现患疾病作为排除标准而非协变量时，LTPA表现出不太有利的关联。
保持活跃可能反映的是一种健康的表型，而非因果性地降低死亡率。
