Vision and Eye Research Institute, School of Medicine, Faculty of Health, Education, Medicine, and Social Care, Anglia Ruskin University, East Road, Cambridge, CB1 1PT, UK.
Cambridge Centre for Sport and Exercise Sciences, Department of Life Sciences, Anglia Ruskin University, Cambridge, UK.
BMC Public Health. 2020 Jul 20;20(1):1144. doi: 10.1186/s12889-020-09255-7.
Self-report in people with age-related macular degeneration (AMD) shows that they lead less active lifestyles. Physical activity is important as it has been shown to improve quality of life, reduce co-morbidity and also slow down the progression of AMD. Self-reported measures of physical activity are prone to subjective biases and therefore less accurate in quantifying physical activity. This study compared self-reported and objective (accelerometer-based) physical activity levels and patterns in older adults with AMD.
Data were collected in 11 AMD subjects with binocular vision loss (aged 76 ± 7 years), 10 AMD subjects with good binocular vision (aged 76 ± 7 years), and 11 controls (aged 70 ± 4 years). Binocular vision was established using visual acuity score. Contrast sensitivity and visual fields were also measured. Self-reported sedentary behaviour and moderate-to-vigorous physical activity (MVPA) was assessed using the Global Physical Activity Questionnaire. Objective measurements were obtained with an Actigraph GT3X accelerometer being worn for seven consecutive days on the hip. The objective physical activity measures were sedentary behaviour, light physical activity, MVPA, and step count.
Objectively measured MVPA was 33-34% higher for controls compared to both AMD groups (p < 0.05). There were no group differences for any of the other objectively measured physical activity variables and self-reported physical activity variables were also not significantly different (all p > 0.05). Comparing the objective with the self-report physical activity measure showed that all groups under-reported their sedentary behaviour and MVPA, but controls under-reported their MVPA more than both AMD groups (p < 0.05). Weak to moderate correlations were observed between the severity of vision loss and objective physical activity measures (all - 0.413 ≥ r ≤ 0.443), while correlations for self-reported physical activity measures were less strong (all - 0.303 ≥ r ≤ 0.114).
People with AMD, irrespective of whether they were vision impaired, were better able to estimate the time spent in MVPA compared to controls. However, objectively measured MVPA, was higher in controls than AMD subjects. Although clinicians may use self-report to monitor the compliance of AMD subjects with any prescribed exercise programs, they should be aware that a valid comparison with healthy controls can only be made when MVPA is objectively measured.
年龄相关性黄斑变性（AMD）患者的自我报告显示，他们的生活方式不太活跃。身体活动很重要，因为它已被证明可以提高生活质量、减少合并症，并且还可以减缓 AMD 的进展。自我报告的身体活动测量方法容易受到主观偏见的影响，因此在量化身体活动方面不太准确。本研究比较了 AMD 老年人的自我报告和客观（基于加速度计）身体活动水平和模式。
在 11 名患有双眼视力丧失的 AMD 受试者（年龄 76±7 岁）、10 名双眼视力良好的 AMD 受试者（年龄 76±7 岁）和 11 名对照者（年龄 70±4 岁）中收集数据。双眼视力采用视力评分确定。还测量了对比敏感度和视野。使用全球体力活动问卷评估自我报告的久坐行为和中高强度体力活动（MVPA）。使用佩戴在臀部的 Actigraph GT3X 加速度计连续七天进行客观测量。客观的身体活动测量包括久坐行为、轻度体力活动、MVPA 和步数。
与 AMD 组相比，对照组的客观测量 MVPA 高 33-34%（p<0.05）。对于其他任何客观测量的身体活动变量和自我报告的身体活动变量，各组之间没有差异（均 p>0.05）。将客观测量与自我报告的身体活动测量进行比较表明，所有组都低估了他们的久坐行为和 MVPA，但对照组比 AMD 组更低估了他们的 MVPA（p<0.05）。与客观身体活动测量相比，视力丧失严重程度与客观身体活动测量呈弱至中度相关（均 -0.413≤r≤-0.443），而与自我报告身体活动测量的相关性较弱（均 -0.303≤r≤-0.114）。
无论是否视力受损，AMD 患者估计 MVPA 时间的能力都比对照组好。然而，在对照组中，客观测量的 MVPA 高于 AMD 受试者。虽然临床医生可能会使用自我报告来监测 AMD 患者对任何规定运动计划的依从性，但他们应该意识到，只有当 MVPA 被客观测量时，才能与健康对照组进行有效的比较。
