Scientific Results: Multimorbidity as a predictor of mortality in companion dogs

September 30, 2026 - 8 minutes read

[vc_row][vc_column][vc_message message_box_color=”violet” icon_fontawesome=”fa fa-paw”]Posts in our Scientific Results series introduce recent papers published in the scientific literature by members of the Dog Aging Project research team. Follow this series to learn more about the scientific questions we’re asking, the kinds of results we’re getting, and what it all means for you and your dog.[/vc_message][/vc_column][/vc_row][vc_row][vc_column][vc_column_text]

Author

Eric R. Foreman

Who worked on this research?

Eric R. Foreman
Laura Corlin
Kate E. Creevy
Jessica M. Hoffman
Dog Aging Project Consortium

Where was it published?

GeroScience, the official journal of the American Aging Association (AGE)

What is this paper about?

This study is about what happens when dogs become multimorbid. The term “multimorbidity” simply means having two or more health conditions at the same time. The researchers wanted to find out if dogs that develop several conditions as they get older are more likely to die sooner than dogs with fewer health problems. They also wanted to learn more about aging because pet dogs share many similarities with humans, including their home environment and medical care. Studying dogs can help scientists better understand how aging and disease work in both dogs and people.

What they did:

The researchers looked at health information from more than 50,000 pet dogs in the Dog Aging Project, a long-term study that follows dogs throughout their lives. They reviewed health records reported by dog owners to see how conditions accumulate as dogs age. They also looked for health problems that often happen together and studied whether dogs with multiple conditions were more likely to die during the study.

What they discovered:

The researchers found that dogs with more health problems had a higher risk of dying than dogs with fewer health problems. They also found that aging was the biggest reason dogs developed multiple conditions. Some combinations of conditions appeared to be more dangerous when they occurred together than when they occurred alone. Health conditions such as osteoarthritis, being overweight, and cancer were common among dogs with multiple illnesses. Overall, the study showed that a dog’s overall health, not just one condition, can be an important clue to how long it may live. The findings also suggest that studying pet dogs can help scientists learn more about aging-related diseases in humans.

What do these results mean for me and my dog?

This study reinforces that aging is a process that affects the whole dog, not just one part of its body. The researchers found that dogs often develop more health problems as they get older, and dogs with multiple health conditions are at greater risk of death than dogs with fewer health issues. These findings help us better understand what healthy aging looks like and why it is important to pay attention to a dog’s overall health as it ages.

For Dog Aging Project participants, this research highlights the value of tracking all aspects of a dog’s health over time. Conditions such as osteoarthritis, excess weight, dental disease, and cancer may seem unrelated, but they often occur together and influence a dog’s well-being. By reporting changes in their dogs’ health, participants help researchers learn how multimorbidity develops and affects lifespan.

The results also remind us that healthy aging is about more than preventing a single disease. Small actions, such as maintaining a healthy weight, staying physically active, keeping up with veterinary visits, and addressing health concerns early, may help support a dog’s long-term health and quality of life. While aging itself cannot be stopped, understanding how health conditions build up over time may help owners make informed decisions that support healthier aging. 

Most importantly, this study shows why Dog Aging Project participants’ contributions matter. Every survey, health update (through VEMRs), and shared experience adds to a growing understanding of how dogs age. The information provided by tens of thousands of participating Pack Members is helping researchers identify patterns that could lead to better ways to predict health risks, improve care for aging dogs, and deepen our understanding of aging in both dogs and humans.

*Note: If you have concerns about your dog’s health, we encourage you to discuss these concerns with your primary care veterinarian. Suggestions for a treatment plan are best recommended by the veterinarian who has a relationship with your dog and understands their medical history.

Where can I learn more?

Foreman, E.R., Corlin, L., Creevy, K.E. et al. Multimorbidity as a predictor of mortality in companion dogs. GeroScience (2026). https://doi.org/10.1007/s11357-026-02342-4

Abstract

Multimorbidity, the presence of two or more conditions, is associated with a higher risk of death as individuals age. However, modeling multimorbidity in laboratory animals is difficult, if not impossible, because specific conditions are seldom individually diagnosed and treated in these settings. Because of their shared environment, physiology, and genetic diversity, and because they are medically managed as individuals, companion dogs have potential to serve as a translational multimorbidity model. Yet it is unknown how diagnoses accumulate over time, how these diagnoses are associated with mortality, and which multimorbid condition combinations are the most prevalent and hazardous. Utilizing owner-reported data from over 50,000 dogs in the Dog Aging Project (DAP), we assessed how multimorbidities develop, learned which are the most prevalent, and evaluated their impact on survival. Like in humans, we show that the accumulation of conditions is associated with an increased risk of death in dogs. We also present data suggesting that future reported condition rates vary depending on the conditions a dog’s owner already has reported. Not surprisingly, our analysis reveals that the overall canine aging process appears to be the driving factor behind disease development, more so than other covariates. Through classifying multimorbidities, we found that almost all either exhibit a synergistic effect or are driven by a single, predominant condition. In both cases, osteoarthritis, overweight, and cancer were highly prevalent throughout. This analysis expands on previously conducted DAP work and further highlights the usefulness of the companion dog as a translational model for human aging.

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