However, neither our recent study (forthcoming), nor Dodd et al.’s 2021 study, showed any increased risk of lower urinary tract dysfunction in vegan cats. Dodd et al. included 1,026 cats whose diets were known, of whom 187 (18%) were fed vegan diets. We included 1,369 cats, of whom 127 (9%) were fed vegan diets. The prevalence of lower urinary tract dysfunction was not statistically significantly different between cats fed vegan and meat-based diets, in either study. Hence, this concern appears to have been unfounded.
Dodd has:
Considering the suggested increased risk of urinary tract diseases in cats fed PB diets [22], this health disorder was chosen for sample size estimation. Assuming the proportion of cats fed MB with urinary tract disorders was 4%, calculation of the sample size comparing two different proportions with the estimation that three times as many cats fed PB would have urinary tract disorders (12%), yielded a required sample size of 116 cats per diet category.
If I’m reading this correctly, if urinary tract disorders were 8% in vegan cats compared to 4% in meat-eating ones they probably would have ended up with a result of “no significant difference”?
Then this is not the right test for the question we’re talking about. This study is saying “we didn’t find strong evidence that vegan diets increase the risk of lower urinary tract dysfunction in vegan cats” but Knight is interpreting it as if it says “we found strong evidence that vegan diets don’t increase the risk of lower urinary tract dysfunction in vegan cats”.
Hi Jeff, I heard back from Andrew Knight who researches this issue. His findings suggest that it’s not actually an issue. I updated the post. He highlights this link: https://sustainablepetfood.info/vegetarian-feline-diets/#4
Dodd has:
If I’m reading this correctly, if urinary tract disorders were 8% in vegan cats compared to 4% in meat-eating ones they probably would have ended up with a result of “no significant difference”?
That’s how I understand it too.
Then this is not the right test for the question we’re talking about. This study is saying “we didn’t find strong evidence that vegan diets increase the risk of lower urinary tract dysfunction in vegan cats” but Knight is interpreting it as if it says “we found strong evidence that vegan diets don’t increase the risk of lower urinary tract dysfunction in vegan cats”.