Background: The association between obesity and diabetes mellitus (DM) in dogs remains controversial.
Objective: To study the potential association between prior obesity and DM in a case-control study. Animals: Electronic records from a large veterinary clinical database.
Methods: 6,611 diabetic dogs (cases) were identified, with 94% having at least 10 hospital visits over a defined monitoring period (median 6y, range 4-9y) prior to diagnosis. Three controls per case were selected using bootstrap matching, matched for breed, sex, neutered status and age. These controls had a similar frequency and duration of visit history. Body condition was categorised as underweight, ideal, overweight and obese. For statistical analysis, odds ratios (OR) were calculated, and univariate and multivariate logistic regression models were constructed.
Results: The odds of developing DM and body condition were significantly associated, with OR of 0.39 (0.15-0.83 95% CI), 2.05 (1.91-2.20) and 4.09 (3.79-4.41) for the underweight, overweight and obese categories, respectively, compared with the ideal category. There was an interaction between sex and body condition, whereby the odds of developing DM were greater in female compared with male dogs in obese condition, but greater in male compared with female dogs in ideal and overweight condition. Finally, there was a strong positive association between duration of time spent in obese condition and the OR for developing DM (Figure). Conclusions and Clinical Importance: A strong temporal association exists between prior obesity and the development of DM in pet dogs. These results can help guide future research in this area.
