Arizona Canine Cognition Center, School of Anthropology, University of Arizona, Tucson, AZ, USA.
Canine Companions for Independence, National Headquarters, Santa Rosa, CA, USA.
Geroscience. 2023 Apr;45(2):645-661. doi: 10.1007/s11357-022-00655-8. Epub 2022 Sep 21.
Canine cognitive dysfunction (CCD) is a form of dementia that shares many similarities with Alzheimer's disease. Given that physical activity is believed to reduce risk of Alzheimer's disease in humans, we explored the association between physical activity and cognitive health in a cohort of companion dogs, aged 6-18 years. We hypothesized that higher levels of physical activity would be associated with lower (i.e., better) scores on a cognitive dysfunction rating instrument and lower prevalence of dementia, and that this association would be robust when controlling for age, comorbidities, and other potential confounders. Our sample included 11,574 companion dogs enrolled through the Dog Aging Project, of whom 287 had scores over the clinical threshold for CCD. In this observational, cross-sectional study, we used owner-reported questionnaire data to quantify dog cognitive health (via a validated scale), physical activity levels, health conditions, training history, and dietary supplements. We fit regression models with measures of cognitive health as the outcome, and physical activity-with several important covariates-as predictors. We found a significant negative relationship between physical activity and current severity of cognitive dysfunction symptoms (estimate = - 0.10, 95% CI: - 0.11 to - 0.08, p < 0.001), extent of symptom worsening over a 6-month interval (estimate = - 0.07, 95% CI: - 0.09 to - 0.05, p < 0.001), and whether a dog reached a clinical level of CCD (odds ratio = 0.53, 95% CI: 0.45 to 0.63, p < 0.001). Physical activity was robustly associated with better cognitive outcomes in dogs. Our findings illustrate the value of companion dogs as a model for investigating relationships between physical activity and cognitive aging, including aspects of dementia that may have translational potential for Alzheimer's disease. While the current study represents an important first step in identifying a relationship between physical activity and cognitive function, it cannot determine causality. Future studies are needed to rule out reverse causation by following the same dogs prospectively over time, and to evaluate causality by administering physical activity interventions.
犬认知功能障碍（CCD）是一种与阿尔茨海默病具有许多相似之处的痴呆症。鉴于运动被认为可以降低人类患阿尔茨海默病的风险，我们在一组年龄在 6-18 岁的伴侣犬中探索了运动与认知健康之间的关联。我们假设，更高水平的身体活动与认知功能障碍评分较低（即更好）和痴呆症患病率较低有关，并且在控制年龄、合并症和其他潜在混杂因素后，这种关联仍然成立。我们的样本包括通过犬老化项目招募的 11574 只伴侣犬，其中 287 只犬的认知功能障碍评分超过了临床阈值。在这项观察性的横断面研究中，我们使用主人报告的问卷数据来量化狗的认知健康（通过验证的量表）、身体活动水平、健康状况、训练历史和膳食补充剂。我们拟合了以认知健康为结果的回归模型，并以身体活动为预测因子，同时考虑了几个重要的协变量。我们发现，身体活动与当前认知功能障碍症状的严重程度（估计值为-0.10，95%CI：-0.11 至-0.08，p<0.001）、6 个月间隔内症状恶化程度（估计值为-0.07，95%CI：-0.09 至-0.05，p<0.001）以及犬是否达到临床认知功能障碍水平（比值比为 0.53，95%CI：0.45 至 0.63，p<0.001）之间存在显著的负相关关系。身体活动与犬的认知结果显著相关。我们的研究结果表明，伴侣犬作为研究身体活动与认知衰老之间关系的模型具有重要价值，包括可能对阿尔茨海默病具有转化意义的痴呆症方面。虽然目前的研究代表了识别身体活动与认知功能之间关系的重要第一步，但它不能确定因果关系。需要进一步的研究来排除通过随时间前瞻性地跟踪相同的犬来排除反向因果关系，并通过实施身体活动干预来评估因果关系。
