Insulin Sensitivity Decreases with Obesity, and Lean Cats with Low Insulin Sensitivity are at Greatest Risk of Glucose Intolerance with Weight Gain

Abstract

This study quantifies the effects of marked weight gain on glucose and insulin metabolism in 16 cats which increased their weight by an average of 44.2% over 10 months. Significantly, the development of feline obesity was accompanied by a 52% decrease in tissue sensitivity to insulin and diminished glucose effectiveness. In addition, glucose intolerance and abnormal insulin response occurred in some cats. An important finding was that normal weight cats with low insulin sensitivity and glucose effectiveness were at increased risk of developing impaired glucose tolerance with obesity. High basal insulin concentrations or low acute insulin response to glucose also independently increased the risk for developing impaired glucose tolerance. Male cats gained more weight relative to females and this, combined with their tendency to lower insulin sensitivity and higher insulin concentrations, may explain why male cats are at greater risk for diabetes. Results suggest an underlying predisposition for glucose intolerance in some cats, which is exacerbated by obesity. These cats may be more at risk of progressing to overt type 2 diabetes mellitus.

Incidence of Diabetes Mellitus in Insured Swedish Cats in Relation to Age, Breed and Sex

“…The increased risk of DM in male cats may be related to 2 factors. First, male cats are predisposed to obesity,25 a major risk factor for DM, and secondly, male cats tend to have lower insulin sensitivity than female cats 26. The male predilection for DM interestingly was not evident in the Burmese breed, in concordance with other studies 8, 9.…”

“…Neutering alone does not seem to decrease insulin sensitivity, but rather increases the risk of obesity. Neutered cats gain weight more easily compared to intact cats,27, 28, 29 and subsequent weight gain leads to decreased insulin sensitivity 26, 30. Therefore, according to these studies, it is the increased risk of obesity after neutering that appears to be the contributing factor to the increased occurrence of DM in neutered cats 8, 31.…”

Histomorphology of Liver, Testicle and Body Fat in Farm Rabbits Fed with an Obesogenic Diet During the Peripuberal Period

“…Beginning on day "0" of the experiment, until its end, every seven days animal weights were recorded, as well as measurements were taken of height and body length using a flexible metric tape (dates not shown) in order to estimate body mass index, according to the model used for cats (Appleton et al, 2001).…”

Dosing obese cats based on body weight spuriously affects some measures of glucose tolerance

“…In the current 103 study, we examined the effects of body weight and body condition on variables including 104 peak and 2-min glucose after glucose administration, fasting glucose, glucose dose (0.3 and 105 0.5 g/kg), and measures of glucose tolerance such as T ½ and 2-h glucose concentration. We 106 utilized blood glucose concentration data from glucose tolerance tests and the first 2 min 107 from insulin sensitivity test previously performed at our laboratory in 16 cats before and after 108 weight gain [15,23]. In the original study, 16 (10 spayed females, 6 castrated males) clinically 109 healthy research cats between 1 and 5 yr of age (most in ideal body condition) underwent 110 glucose tolerance and insulin sensitivity tests to provide baseline data prior to weight gain 111 [23].…”

“…We 106 utilized blood glucose concentration data from glucose tolerance tests and the first 2 min 107 from insulin sensitivity test previously performed at our laboratory in 16 cats before and after 108 weight gain [15,23]. In the original study, 16 (10 spayed females, 6 castrated males) clinically 109 healthy research cats between 1 and 5 yr of age (most in ideal body condition) underwent 110 glucose tolerance and insulin sensitivity tests to provide baseline data prior to weight gain 111 [23]. The cats were offered a combination of 2 commercially available extruded foods, with…”