Departments of Epidemiology, Boston University School of Public Health, Massachusetts.
Community Health Sciences, Boston University School of Public Health, Massachusetts.
Gerontologist. 2019 Sep 17;59(5):e461-e469. doi: 10.1093/geront/gny135.
Caregiving is associated with reduced mortality in recent studies. Investigations of caregiving intensity may reveal an underlying mechanism. However, studies of caregiving intensity and mortality have mixed results, perhaps due to imprecise measurement of caregiving intensity, not accounting for healthier persons likely having greater caregiving involvement, or temporal changes in intensity. We examined the relationship between caregiving intensity (based on tasks performed) and mortality, treating intensity and health status as time-varying, and lagging exposure.
Caregiving tasks among 1,069 women in the Caregiver-Study of Osteoporotic Fractures study (35% caregivers) were assessed at 5 interviews conducted between 1999 and 2009. Caregivers were categorized as high intensity if they assisted a person with dressing, transferring, bathing, or toileting; or as low intensity if they assisted with other instrumental or basic activities of daily living (I/ADLs). Alternatively, high intensity was defined as assisting with more than the median number of I/ADL tasks (median-based measure). Mortality was assessed through 2011. Cox proportional hazards models estimated adjusted hazard ratios (aHR) and 95% confidence intervals based on concurrent intensity, and lagging exposure 2 years.
High-intensity caregivers had significantly lower mortality using the median-based measure after lagging exposure (aHR = 0.55, 0.34-0.89). Similar, but not statistically significant associations were observed in non-lagged analyses (aHR = 0.54, 0.29-1.04) and task-specific intensity (aHRs were 0.61 and 0.51). Low-intensity caregivers had similar mortality rates to noncaregivers in all analyses.
Among older women, high-intensity caregivers had lower mortality rates than noncaregivers. Whether this association extends to other populations merits investigation.
最近的研究表明，照料者的死亡率较低。对照料强度的研究可能揭示其潜在机制。然而，关于照料强度与死亡率的研究结果不一，这可能是由于对照料强度的测量不够精确，没有考虑到健康状况更好的人可能会有更多的照料参与，或者强度的时间变化。我们研究了基于所执行任务的照料强度与死亡率之间的关系，将强度和健康状况视为随时间变化的，并采用滞后暴露。
1999 年至 2009 年期间，在骨质疏松性骨折照料者研究（Caregiver-Study of Osteoporotic Fractures study）中对 1069 名女性进行了 5 次访谈，评估了她们的照料任务。如果照料者协助穿衣、转移、洗澡或上厕所，则被归类为高强度照料者；如果协助其他工具性或基本日常生活活动（I/ADLs），则被归类为低强度照料者。或者，高强度被定义为协助完成的 I/ADL 任务数超过中位数（中位数测量）。通过 2011 年评估死亡率。基于同期强度和滞后暴露 2 年，Cox 比例风险模型估计了调整后的危险比（aHR）和 95%置信区间。
使用中位数测量，滞后暴露后，高强度照料者的死亡率显著降低（aHR = 0.55，0.34-0.89）。在非滞后分析中观察到类似但无统计学意义的关联（aHR = 0.54，0.29-1.04）和特定任务强度（aHR 分别为 0.61 和 0.51）。在所有分析中，低强度照料者的死亡率与非照料者相似。
在老年女性中，高强度照料者的死亡率低于非照料者。这种关联是否扩展到其他人群值得进一步研究。
