QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Klinkenberg, H. Articles by Hedhammar, A. Search for Related Content PubMed PubMed Citation Articles by Klinkenberg, H. Articles by Hedhammar, A.

---

Supplement: The WALTHAM International Sciences Symposia Innovations in Companion Animal Nutrition: Obesity

Feeding, Exercise, and Weight Identified as Risk Factors in Canine Diabetes Mellitus^1,2

Department of Small Animal Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden

³ To whom correspondence should be addressed. E-mail: ake.hedhammar{at}kirmed.slu.se.

KEY WORDS: • dog • diabetes mellitus • diet • exercise • weight

Overweight and lack of exercise are well documented as risk factors in human type 2 diabetes and also affect clinical control of type 1 diabetes. Contrary to human and also feline diabetes most canine diabetes mellitus (CDM) is thought to be of type 1, even though most clinical cases are not well classified. Obesity has been proven to be a significant risk factor in feline type 2 diabetes (1) and is thought to account for the variations in insulin responses in all types of diabetic dogs (2).

An interrelationship among CDM, obesity, and endometritis was proven in a postmortem study over 40 y ago (3), but in dogs (and cats) effects of exercise have not been evaluated as risk factors for diabetes. To evaluate the effects of dietary intake and exercise on health and disease in individual dogs as well as in defined canine populations, a combined mail and telephone questionnaire was developed and validated (4).

As part of an investigation into multifactorial diseases in dogs that might be of value to human medicine, we are conducting epidemiologic and molecular genetic studies, making use of access to insurance data and to population-based cases and controls, matched by breed, sex, and age (5). To identify risk factors for CDM for further studies on molecular genetics and environmental exposure, we conducted an epidemiologic pilot study focusing on feeding, exercise, and weight.

	MATERIAL AND METHODS

TOP MATERIAL AND METHODS RESULTS DISCUSSION LITERATURE CITED

 
Dogs

Twenty consecutive dogs diagnosed with CDM at the Small Animal Clinic at the Swedish University of Agricultural Sciences between 2000 and 2003 were included as cases. A control group of 40 dogs matched for age, sex, and breed was recruited from the registries at the Swedish Kennel Club.

Design and questionnaire

Breed, sex, and age at first symptoms of CDM in each dog included as cases were used to select controls. Owners of controls were accessed in the registries of dogs and owners of the Swedish Kennel Club. The owners of cases and controls received a questionnaire by mail regarding each dog before first symptoms of CDM were seen in cases and at a similar age period for controls. One week after receiving the questionnaire, the owners were called by phone, and survey data were recorded by the first author (H.K.).

The questionnaire contained questions on feeding patterns and diet (ad libitum vs. restricted feeding), proportions of total diet (commercial dry and canned food, table scraps, and homemade diets), frequency of feeding treats (times/wk), owner-perceived activity level (calm, moderately active, and lively), and exercise pattern by walks (on leash and free) minutes per day and distance per day. We also registered whether the dog had any intense training (hunting, training, and cycling) by average number of occasions/y and min/occasion before the first symptoms of CDM. Owner-perceived body condition score (underweight, normal, and overweight) was recorded at the time of first symptoms of CDM as well as for an extended period of life. Serious illness preceding CDM was also recorded.

Statistical analyses

Chi-square analysis in Excel (Microsoft) was used to determine differences in categorical variables between cases and controls. Continuous variables were compared in Excel (Microsoft) using Student's t test (6). A value of P < 0.05 was considered statistically significant.

	RESULTS

TOP MATERIAL AND METHODS RESULTS DISCUSSION LITERATURE CITED

 
Owners of 19 of 20 case subjects (95%) and owners of 40 of 59 of the originally matched control subjects (68%) responded to the telephone survey. Reasons for no response were that the owners were not reached (1 case, 9 controls), dogs were not alive (6 controls), or were unwilling to participate (4 controls).

The consecutive series of cases consisted of 16 intact females and 4 intact males. The mean age was 9.2 y (range 4–13.5) at the time of first clinical signs of CDM. The cases were from 8 breeds: Border collie (n = 6), Swedish elkhound (n = 4), Springer spaniel (n = 3), Labrador retriever (n = 2), West highland white terrier (n = 2), Cairn terrier (n = 1), Rottweiler (n = 1), and Polski ocwzarek nizinni (n = 1). The controls according to design were of the same age and sex and of the same breeds.

The results showed no statistically significant difference between cases and controls in the proportion fed homemade diets or table food versus commercial diets. However, cases tended to receive less commercial dry dog food and more canned dog food, homemade diets, and table scraps than controls. Cases also received treats more often than controls (P < 0.03; Table 1).

View larger version (12K): [in this window] [in a new window]   FIGURE 1  Frequency of intense training for 6 cases and 23 controls, P < 0.01.

View larger version (13K): [in this window] [in a new window]   FIGURE 2  Distribution of overweight BCS (body condition score) in dogs at first diagnosis of CDM (19 cases vs. 40 controls).

View larger version (11K): [in this window] [in a new window]   FIGURE 3  Distribution of long-term overweight BCS (body condition score) in 19 dogs with CDM compared with 40 age-matched controls.

	DISCUSSION

TOP MATERIAL AND METHODS RESULTS DISCUSSION LITERATURE CITED

 
Despite the small number of cases and lack of further classification by type of diabetes, several significant differences between cases and controls were identified. An effect of owner-perceived body condition score at the time of first symptoms of CDM might be anticipated, although most CDM cases reported on in the literature are classified as late-onset type 1 diabetes, a subclass of type 1. Owner-perceived overweight over a greater part of the dog's life was also related to cases vs. controls, indicating a possible long-term effect in the etiology of at least a subset of CDM cases. As with other indicated risk factors, analysis of this effect in a larger sample of cases classified according to type of diabetes would prove to be very helpful in further studies of CDM.

The significant positive effect of intense training was striking in that not all cases could be expected to receive such training because of the origin of the breed. Breed matching and the fact that a large fraction of the dogs were of working breeds allowed us to identify these effects even though the number of dogs was small.

The breed distribution in this case series of consecutive dogs with a diagnosis of CDM is an overrepresentation of working breeds, somewhat different from what is seen in other published studies including a recent report from England (7) but in agreement with further analyses of our own published insurance data from Sweden (8).

An overrepresentation of females as well as a correlation with periods of heat in cases and a diagnosis of endometritis in controls indicate that hormonal effects may be involved in the etiology of CDM in females. It is worth noting that all female cases were intact (as well as male cases) and had not contracted endometritis before the appearance of symptoms of CDM, indicating that neutering might not only have a positive effect on insulin control in diabetic dogs but may also be protective in the etiology of CDM.

A significant effect of higher frequency of "giving treats" in cases, as well as a tendency for cases to receive more canned food, homemade diets, and table food than controls, are interpreted as factors contributing to overweight in these dogs as shown earlier in a dietary survey of a defined Swedish population of dogs.

The present study identified feeding patterns, exercise, and body condition score as significant risk factors in CDM that should be taken into account in the design of preventive measures as well as the design of research to elucidate the multifactorial aspects of diabetes incidence in dogs. This study has also identified the value of breed, sex, and age matching for further studies of molecular genetics and nutritional impacts on canine diabetes.

	FOOTNOTES

 
¹ Published in a supplement to The Journal of Nutrition. Presented as part of The WALTHAM International Nutritional Sciences Symposium: Innovations in Companion Animal Nutrition held in Washington, DC, September 15–18, 2005. This conference was supported by The WALTHAM Centre for Pet Nutrition and organized in collaboration with the University of California, Davis, and Cornell University. This publication was supported by The WALTHAM Centre for Pet Nutrition. Guest editors for this symposium were D'Ann Finley, Francis A. Kallfelz, James G. Morris, and Quinton R. Rogers. Guest editor disclosure: expenses for the editors to travel to the symposium and honoraria were paid by The WALTHAM Centre for Pet Nutrition.

² Author disclosure: no relationships to disclose.

	LITERATURE CITED

TOP MATERIAL AND METHODS RESULTS DISCUSSION LITERATURE CITED

 

1. Donoghue S, Scarlett JM. Diet and feline obesity. J Nutr. 1998;128: 12 Suppl:2776S–8S.[Free Full Text]

2. Mattheeuws D, Rottiers R, Kaneko JJ, Vermeulen A. Diabetes mellitus in dogs: relationship of obesity to glucose tolerance and insulin response. Am J Vet Res. 1983;45:98–103.

3. Krook L, Larsson S, Rooney J. R. The interrelationship of diabetes mellitus, obesity, and pyometra in the dog. Am J Vet Res. 1960;21:120–1277.[Medline]

4. Sallander MH, Hedhammar Å, Rundgren M, Lindberg JE. Repeatability and validity of a combined mail and telephone questionnaire on demographics, diet, exercise and health status in an insured-dog population. Prev Vet Med. 2001;50:35–51.[Medline]

5. Hedhammar Å, Nödtvedt A, Sallander M, Andersson G, Salmon-Hillbertz N, Björnerfeldt S, Malm S, Ferm K, Egenvall A. Swedish insurance data and canine registries used to target populations and individual dogs for studies on functional and comparative genomics. Abstract. Proceedings 2nd International conference: Advances in Canine and Feline Genomics. Utrecht, October 2004.

6. Wayne D. Biostatistics: a foundation for analysis in the health sciences. 4th ed.New York: John Wiley & Sons; 1995.

7. Davison LJ, Herrtage M, Catchpole B. Study of 253 dogs in the United Kingdom with diabetes mellitus. Vet Rec. 2005;156:467–71.[Abstract/Free Full Text]

8. Egenvall A, Bonnett B, Olson P, Hedhammar A. Gender, age and breed pattern of diagnoses for veterinary care in insured dogs in Sweden during 1996. Vet Rec. 2000;146:551–7.[Abstract/Free Full Text]

This article has been cited by other articles:

				A. J. German The Growing Problem of Obesity in Dogs and Cats J. Nutr., July 1, 2006; 136(7): 1940S - 1946S. [Abstract] [Full Text] [PDF]

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Klinkenberg, H. Articles by Hedhammar, A. Search for Related Content PubMed PubMed Citation Articles by Klinkenberg, H. Articles by Hedhammar, A.