Obesity in Cats – Overview
- An excess of body fat, frequently resulting in adverse health effects
- Even a moderate excess in body fat can increase incidence of disease (known as “morbidity”) and reduce lifespan
Mean Age and Range
- All ages, with the greatest prevalence (nearly 50%) in middle-aged cats
Predominant Sex
- Most common in neutered, indoor pets
Signs/Observed Changes in the Pet
- Weight gain
- Exercise intolerance may be reported
- Excess body fat and high body condition score or BCS (estimate of weight status [under- or overweight] as compared to normal weight)
Causes
- Obesity is caused by an imbalance between calorie or energy intake and calorie or energy expenditure, with intake exceeding expenditure
- Neutering, decreased opportunities for activity, and age can reduce expenditure of energy
- Overfeeding of high calorie foods, frequently alternating foods, and provision of excess treats contribute to excess calorie or energy intake
- Low levels of thyroid hormone (known as “hypothyroidism”), insulin-secreting tumor (known as an “insulinoma”), or high levels of steroids produced by the adrenal glands (known as “hyperadrenocorticism” or “Cushing’s syndrome”) are infrequent causes of obesity
Treatment
Health Care
- Weight loss, induced by reducing calorie intake below calorie or energy expenditure
- Successful weight loss also requires long-term maintenance of the reduced weight
- Weight loss and maintenance of reduced weight depend on changes in the way the owner feeds and interacts with the pet
- The owner should assess and monitor the body condition score (estimate of weight status [under- or overweight] as compared to normal weight) of his or her pet; your pet’s veterinarian will provide information on assessing BCS
Activity
- Calorie or energy restriction results in compensatory decreases in basal energy expenditure or metabolism; increased activity helps compensate for this decrease in metabolism and provides alternate opportunities for owner-pet interactions
- Leash walking for dogs and trained cats—at least 15 minutes twice daily
- Activities such as “fetch,” interactive toys for cats, or playing with a laser light
- Food balls—built to hold treats or kibbles and randomly release them while the dog or cat plays; food used in the ball must be included as part of the daily calorie allowance
Diet
- Get written instructions regarding specific amounts to provide, using the agreed upon reducing diet (a “cup” of food refers to an 8-oz measuring cup); measure food carefully to ensure appropriate amount is being fed
- Protein—increased dietary protein facilitates loss of body fat, while minimizing loss of lean body mass (LBM), which is the metabolically active tissue—preserving LBM should help with long-term weight control by maintaining a higher resting energy requirement; protein also stimulates metabolism, increases energy expenditure, and contributes to the feeling of being full or satisfied (known as “satiety”)
- Fiber—dietary fiber provides little dietary energy, so it helps reduce total calories in the diet; fiber also stimulates intestinal metabolism and energy utilization, and contributes to the feeling of being full or satisfied (satiety)
- Other dietary factors that may aid in weight management—carnitine, compound necessary for fat metabolism; isoflavones, stimulate energy metabolism and support lean body mass
- Fat—calorie or energy dense, so low-fat diets are lower in energy
- Calories should be restricted, without excessive restriction of essential nutrients; a low-calorie therapeutic diet with an increased nutrient-to-calorie ratio is recommended for weight loss
- Amount fed should target a 1–2% loss in body weight per week; faster weight loss may increase loss of lean body mass and stimulate weight rebound once weight loss is achieved
- High moisture diets can be used to reduce calories per serving; this approach appears to be more effective for cats versus dogs, as cats tend to control their intake based on volume
- If the client is not willing to use a therapeutic diet, severe calorie restriction should be avoided; a food diary can be used to record current intake over 3–7 days—subsequently, the pet should be fed 10–20% less than it previously received
- Treats are often part of the owner-pet bond; complete avoidance of treats is a hurdle to compliance with weight loss programs—instead, offer a “treat allowance” of 10% of the daily calories and use low-calorie treats suitable for dogs or cats, as directed by your pet’s veterinarian
Medications
- Medications presented in this section are intended to provide general information about possible treatment. The treatment for a particular condition may evolve as medical advances are made; therefore, the medications should not be considered as all inclusive
- Dirlotapide (Slentrol, Pfizer Animal Health)—approved only for use in dogs; can cause decreased appetite sufficient to lead to weight loss; use with a diet formulated for weight loss; appetite and weight will rebound after discontinuing dirlotapide; talk to your pet’s veterinarian about a feeding plan to avoid rebound weight gain
- Mitratapide has a similar mechanism of action; use limited to a single course of treatment
Follow-Up Care
Patient Monitoring
- Frequent communication is important during the weight management program
- Telephone call from clinic to the owner to address any minor questions and to reinforce the importance of the program
- Pet should be weighed in the clinic on a monthly basis; if needed, adjustments in food allowance guidelines should be made at this time
- Once the pet has achieved an ideal body condition score (estimate of weight status [under- or overweight] as compared to normal weight) guidelines should be provided for weight maintenance; continue to measure food, monitor BCS or body weight, and adjust food allowance as needed to maintain the goal weight
Preventions and Avoidance
- Monitor food intake, weight, and body condition score (estimate of weight status [under- or overweight] as compared to normal weight) throughout life to prevent weight gain and obesity
- Maintain a healthy diet and reduce caloric intake if pet starts gaining weight (even small weight gains of 1–2 pounds can be significant in small- and medium-size dogs and in cats)
Possible Complications
- Obesity leads to increased risk for diseases (such as osteoarthritis, diabetes mellitus) or shortened lifespan
Key Points
- Obesity leads to increased risk for diseases (such as osteoarthritis, diabetes mellitus) or shortened lifespan
- Weight loss and maintenance of reduced weight depend on changes in the way the owner feeds and interacts with the pet
- Monitor food intake, weight, and body condition score (estimate of weight status [under- or overweight] as compared to normal weight) throughout life to prevent weight gain and obesity
- Maintain a healthy diet and reduce caloric intake if pet starts gaining weight (even small weight gains of 1–2 pounds can be significant in small- and medium-size dogs and in cats)