Risk factors for the incidence of calcium oxalate uroliths or magnesium ammonium phosphate uroliths for dogs in Ontario, Canada, from 1998 to 2006.
OBJECTIVE
To investigate individual- and community-level contextual variables as risk factors for submission of calcium oxalate (CaOx) uroliths or magnesium ammonium phosphate (ie, struvite) uroliths for dogs to a national urolith center, as determined on the basis of urolith submission patterns.


METHODS
Records of 7,297 dogs from Ontario, Canada, with CaOx or struvite uroliths submitted to the Canadian Veterinary Urolith Centre from 1998 through 2006.


METHODS
Data were analyzed via multilevel multivariable logistic regression.


RESULTS
Individual-level main effects and interactions significantly associated with the risk of submission of CaOx uroliths rather than struvite uroliths included age, sex, breed group, neuter status, body condition, dietary moisture content, diet type, sex-neuter status interaction, sex-age interaction, body condition-age interaction, and breed group-dietary moisture content interaction. In addition, median community family income and being located within a major urban center (ie, Toronto) were significant risk factors for submission of CaOx uroliths, compared with submission of struvite uroliths.


CONCLUSIONS
Individual-level and dietary factors for dogs affected the risk of submission of CaOx uroliths, relative to that of struvite uroliths. Interactions among these variables need to be considered when assessing the impact of these risk factors. In addition, community-level or contextual factors (such as community family income and residing in a densely populated area of Ontario) also affected submission patterns, although most of the variance in the risk for submission of CaOx uroliths, compared with the risk for submission of struvite uroliths, was explained by individual-level factors.
Wisener
Lee V
LV
Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON N1G 2W1, Canada. lwisener@uoguelph.ca
Pearl
David L
DL
Houston
Doreen M
DM
Reid-Smith
Richard J
RJ
Moore
Andrew E
AE
D000818:Animals; D002129:Calcium Oxalate / Q000652:urine*; D004283:Dog Diseases / Q000453:epidemiology* / Q000652:urine; D004285:Dogs / Q000145:classification; D005260:Female; D015994:Incidence; D017616:Magnesium Compounds / Q000652:urine*; D008297:Male; D009864:Ontario / Q000453:epidemiology; D010710:Phosphates / Q000652:urine*; D012044:Regression Analysis; D013045:Species Specificity; D000069877:Struvite; D052878:Urolithiasis / Q000453:epidemiology / Q000652:urine / Q000662:veterinary*
D017616:Magnesium Compounds; D010710:Phosphates; D002129:Calcium Oxalate; D000069877:Struvite