Pet ownership is associated with greater cognitive and brain health in a cross-sectional sample across the adult lifespan

Fully automated deep learning models with smartphone applicability for prediction of pain using the Feline Grimace Scale

This study used deep neural networks and machine learning models to predict facial landmark positions and pain scores using the Feline Grimace Scale© (FGS). A total of 3447 face images of cats were annotated with 37 landmarks. Convolutional neural networks (CNN) were trained and selected according to size, prediction time, predictive performance (normalized root mean squared error, NRMSE) and suitability for smartphone technology. Geometric descriptors (n = 35) were computed. XGBoost models were trained and selected according to predictive performance (accuracy; mean square error, MSE). For prediction of facial landmarks, the best CNN model had NRMSE of 16.76% (ShuffleNetV2). For prediction of FGS scores, the best XGBoost model had accuracy of 95.5% and MSE of 0.0096. Models showed excellent predictive performance and accuracy to discriminate painful and non-painful cats. This technology can now be used for the development of an automated, smartphone application for acute pain assessment in cats.

Pet Ownership, Living Alone, and Cognitive Decline Among Adults 50 Years and Older

Importance

It remains unclear whether pet ownership is associated with cognitive decline and to what extent pet ownership mitigates the association between living alone and cognitive decline.

Objective

To explore the association of pet ownership with cognitive decline, the interaction between pet ownership and living alone, and the extent to which pet ownership mitigates the association between living alone and cognitive decline in older adults.

Design, Setting, and Participants

This cohort study used data from waves 5 (June 2010 to July 2011) to 9 (from June 2018 to July 2019) in the English Longitudinal Study of Ageing. Participants included adults 50 years and older. Data were analyzed from April 1 to June 30, 2023.

Exposures

Pet ownership and living alone in wave 5.

Main Outcomes and Measures

In waves 5 to 9, verbal memory and verbal fluency were assessed, and composite verbal cognition was further calculated.

Results

Of the 7945 participants included, the mean (SD) age was 66.3 (8.8) years, and 4446 (56.0%) were women. Pet ownership was associated with slower rates of decline in composite verbal cognition (β = 0.008 [95% CI, 0.002-0.014] SD/y), verbal memory (β = 0.006 [95% CI, 0.001-0.012] SD/y), and verbal fluency (β = 0.007 [95% CI, 0.001-0.013] SD/y). Three-way interaction tests showed that living alone was a significant modifier in all 3 associations. Stratified analyses showed that pet ownership was associated with slower rates of decline in composite verbal cognition (β = 0.023 [95% CI, 0.011-0.035] SD/y), verbal memory (β = 0.021 [95% CI, 0.008-0.034] SD/y), and verbal fluency (β = 0.018 [95% CI, 0.005-0.030] SD/y) among individuals living alone, but not among those living with others. Joint association analyses showed no significant difference in rates of decline in composite verbal cognition, verbal memory, or verbal fluency between pet owners living alone and pet owners living with others.

Conclusions and Relevance

In this cohort study, pet ownership was associated with slower rates of decline in verbal memory and verbal fluency among older adults living alone, but not among those living with others, and pet ownership offset the associations between living alone and declining rates in verbal memory and verbal fluency. Further studies are needed to assess whether pet ownership slows the rate of cognitive decline in older adults living alone.