Danish Dementia Research Centre, Department of Neurology, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark.
Danish Dementia Research Centre, Department of Neurology, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark.
J Neurol Sci. 2024 Jan 15;456:122856. doi: 10.1016/j.jns.2023.122856. Epub 2023 Dec 22.
Quantitative light reflex pupillometry (qLRP) may be a promising digital biomarker in neurodegenerative diseases such as Alzheimer's disease (AD), as neuropathological changes have been found in the midbrain structures governing the light reflex. Studies investigating test-retest reliability and short-term, intra-subject variability of qLRP in these patient groups are missing. Our objective was therefore to investigate the test-retest reliability and short-term, intra-subject variability of qLRP in a memory clinic setting, where patients with neurodegenerative disease are frequently evaluated.
Test-retest reliability study. We recruited patients from a tertiary memory clinic and qLRP was carried out at a baseline visit and then repeated on day 3-14 and on day 21-35 using a hand-held pupillometer. We evaluated the test-retest reliability of qLRP by calculating intraclass correlation coefficients (ICCs) and intra-subject, short-term variability by fitting linear mixed models. We compared ICCs for subgroups based on age, sex, disease severity (MCI vs. mild dementia), AD diagnosis, and amount of neurodegeneration (cerebrospinal fluid-total tau levels).
In total, 40 patients (mean age 72 years, 15 female, 22 with mild dementia) were included in the study. We found good-excellent reliability (ICC range 0.86-0.93) for most qLRP parameters. qLRP parameters exhibited limited intra-subject variability and we found no large sources of variability when examining subgroups.
qLRP was found to have acceptable test-retest reliability and the study results pave the way for research using longitudinal or cross-sectional measurements to assess the construct in identifying and prognosticating neurodegenerative diseases.
定量光反射瞳孔测量法（qLRP）可能是一种有前途的神经退行性疾病的数字生物标志物，如阿尔茨海默病（AD），因为在调节光反射的中脑结构中已经发现了神经病理学变化。在这些患者群体中，研究定量光反射瞳孔测量法的测试 - 重测可靠性和短期、个体内变异性的研究尚属空白。因此，我们的目的是在经常评估神经退行性疾病患者的记忆诊所环境中研究定量光反射瞳孔测量法的测试 - 重测可靠性和短期、个体内变异性。
测试 - 重测可靠性研究。我们从一个三级记忆诊所招募了患者，并在基线就诊时进行了 qLRP，然后在第 3-14 天和第 21-35 天使用手持式瞳孔计重复进行。我们通过计算组内相关系数（ICC）和线性混合模型拟合来评估 qLRP 的测试 - 重测可靠性。我们根据年龄、性别、疾病严重程度（MCI 与轻度痴呆）、AD 诊断和神经退行性病变程度（脑脊液总 tau 水平）对亚组进行了 ICC 比较。
共有 40 名患者（平均年龄 72 岁，15 名女性，22 名轻度痴呆）纳入了研究。我们发现大多数 qLRP 参数的可靠性良好至优秀（ICC 范围 0.86-0.93）。qLRP 参数显示出有限的个体内变异性，并且当检查亚组时，我们没有发现很大的变异性来源。
qLRP 被发现具有可接受的测试 - 重测可靠性，研究结果为使用纵向或横断面测量来评估该构念以识别和预测神经退行性疾病的研究铺平了道路。
