Evidence is largely limited regarding the extent to which abnormal behavioural profiles, including physical inactivity, sedentary behaviour and inadequate sleep duration, impact long-term health conditions in individuals with pre-existing depression.

To investigate the associations between accelerometer-derived daily movement behaviours and mortality in individuals with pre-existing depression.

Between 2013 and 2015, a total of 10 914 individuals with pre-existing depression were identified from the UK Biobank through multiple sources including self-reported symptoms, records of antidepressant usage and diagnostic recording based on the 10th Revision of the International Classification of Diseases (ICD-10) codes F32–F33. These participants were subsequently followed up until 2021. Wrist-worn accelerometers were used for objective measurement of sleep duration, sedentary behaviour, moderate-to-vigorous physical activity (MVPA) and light physical activity (LPA) over a span of seven consecutive days.

During a median follow-up of 6.9 years, 434 deaths occurred among individuals with pre-existing depression. We observed a U-shaped association between sleep duration and mortality in individuals with pre-existing depression, with the lowest risk occurring at approximately 9 h/day. Both MVPA and LPA exhibited an L-shaped pattern in relation to mortality, indicating that engaging in higher levels of physical activity was associated with lower risk of mortality in individuals with pre-existing depression, but the beneficial effect reached a plateau after 50 min/day for MVPA and 350 min/day for LPA. We found a positive association between sedentary time and mortality, and the risk apparently increased above 8 h/day. Moreover, substituting 1 hour/day of sedentary time with LPA or MVPA was significantly associated with a 12% (hazard ratio: 0.88, 95% CI: 0.83–0.94) and 24% (hazard ratio: 0.76, 95% CI: 0.61–0.94) lower risk of mortality, respectively.

Our study found the beneficial effect of adequate sleep duration, high levels of physical activity and short sedentary time on risk of mortality among individuals with pre-existing depression.

关于异常行为特征（包括缺乏身体活动、久坐行为和睡眠时间不足）对既往抑郁症患者长期健康状况的影响程度，证据在很大程度上是有限的。

调查加速度计衍生的日常运动行为与既往抑郁症患者死亡率之间的关联。

2013 年至 2015 年期间，通过多种来源，包括自我报告的症状、抗抑郁药使用记录和基于国际疾病分类 （ICD-10） 第 10 次修订版代码 F32-F33 的诊断记录，从英国生物样本库中确定了 10 914 名既往抑郁症患者。这些参与者随后接受了随访至 2021 年。腕戴式加速度计用于客观测量连续 7 天的睡眠持续时间、久坐行为、中度至剧烈体力活动 （MVPA） 和轻度体力活动 （LPA）。

在中位随访 6.9 年期间，已有抑郁症的个体中有 434 例死亡。我们观察到既往抑郁症个体的睡眠持续时间与死亡率之间存在 U 形关联，最低风险发生在大约 9 小时/天。MVPA 和 LPA 均表现出与死亡率相关的 L 形模式，表明在已有抑郁症的个体中，从事更高水平的体育活动与较低的死亡风险相关，但 MVPA 的有益效果在 50 分钟/天和 LPA 350 分钟/天后达到平台期。我们发现久坐时间与死亡率之间存在正相关，并且风险明显增加超过 8 小时/天。此外，用 LPA 或 MVPA 代替 1 小时/天的久坐时间与死亡风险降低 12% （风险比： 0.88， 95% CI： 0.83–0.94） 和 24% （风险比： 0.76， 95% CI： 0.61–0.94） 显著相关。

我们的研究发现，充足的睡眠时间、高水平的体育锻炼和较短的久坐时间对既往抑郁症患者的死亡风险有有益影响。