Going with the Flow: Keeping Up with Changes in the Management of FIC
Patient Signalment and Pathophysiology
Feline idiopathic cystitis (FIC) is a sterile, inflammatory process causing signs of lower urinary tract disease (LUTD). It is the most common diagnosis for young cats with LUTD (the second most common being urolithiasis). Feline idiopathic cystitis is important because of the pain and distress it causes patients, and because it is highly associated with house soiling.
Most patients are 2–6 years of age at diagnosis; FIC is uncommon in cats under one year of age. Cats with FIC are often more nervous and fearful than unaffected cats living in the same home.1 Other risk factors include being male, overweight, pedigreed breed, and stress factors, especially conflict with another cat in the home.2
The pathophysiology of FIC is not well understood. It is thought to involve complex interactions between the central nervous system and the endocrine system. Feline idiopathic cystitis is described as an exaggerated sympathetic nervous system response to stress with a blunted endocrine response. Stress appears to be a very important factor in flare-ups of FIC and often precedes a cat's first episode. Cats with FIC have been described as "sensitive cats in a provocative or deficient environment." These cats may be unusually sensitive to changes in their environment and diet.
The Role of Environmental Modification
Environmental modification/enrichment is proving to be a useful tool to help decrease sympathetic overdrive, reduce stress, and prolong time between episodes of FIC.3 Indoor cats need places to climb, scratch, sleep, and hide. Many cats do not like to compete for resources (food, water, hiding and sleeping places). Other stressful factors for cats include the presence of other cats in the household, as well as changes in environment, weather, activity in the household, the owner's work schedule, additions or removals of animals or people from the household, and changes in diet.4 Litter boxes should be in a quiet and easily accessible area and should be scooped daily and cleaned weekly.
In a study of 46 client-owned cats, multimodal environmental modification (MEMO) was instituted and the cats were followed for 10 months.3 The components of MEMO are available for owners and veterinarians on the website of the Indoor Cat Initiative (http://indoorpet.osu.edu). Significant decreases were documented in signs of LUTD, fearfulness, nervousness, and aggressive behavior. As well, owners reported decreases in clinical signs referable to the respiratory and gastrointestinal tracts.
Dietary Management of FIC
Dietary management needs to be tailored to the patient. Since no specific cause has been conclusively identified, a trial-and-error process is necessary to find the best dietary treatment for each cat. The key nutrients are:
Water
A couple of uncontrolled studies have found a beneficial effect on FIC in cats fed canned diets.5,6 Water intake in cats is higher when fed canned diets and the resulting dilute urine might reduce the concentration of irritating substances in the urine. On the other hand, one latest study, only published as an abstract,7 comparing four urinary diets (2 dry, 2 canned) did not find an improvement of the canned over the dry version. Overall, the recommendation is to feed canned, but in cats eating dry, make a really slow transition (offering the new food in a different dish so the cat can make the choice) to minimize the stress associated to food change.
Energy
Urinary problems are more common in obese cats and keeping them lean is a priority. Canned diets are less energy dense than kibble and can help the cat feel more satiated.8 Whatever the chosen diet, free feeding can result in overweight cats. On the other hand, restricting the access to food might result in stress for the cat. Each case should be carefully evaluated to decide on the best feeding method.
Other: Inflammation and Stress Management
The use of immunomodulatory nutrients like long-chain omega-3 fatty acids (eicosapentaenoic and docosahexaenoic acids) and antioxidants could potentially help with bladder inflammation, although there are no published studies supporting their efficacy at this time. The same goes towards nutrients that can potentially help with stress reduction like tryptophan and milk hydrolysates. Although there are some data that they can reduce stress, studies regarding their efficacy on FIC cats have not been published. There is one abstract7 where cats fed a diet supplemented with omega-3 fatty acids, antioxidants, and stress management nutrients, can perform better in cats with FIC than a urinary diet without these strategies; however, the dose and specific nutrients are not detailed and the study has not yet undergone peer review to offer a specific recommendation at this point.
Therapeutic canned urinary diets can be used for this disease. They will stimulate diuresis and can help manage other problems related to lower urinary tract disease such as urolithiasis and urethral plugs. Some of these diets have salt to produce a dilute urine even when fed dry (not all). Most of these are formulated to address both struvite and calcium oxalate urolithiasis, with controlled amounts of phosphorus, nitrogen, magnesium, calcium and oxalate, and adequate stone inhibitors (such as citrate).
A good diet history is important: cats eating dry diets can be transitioned to a canned diet that they like and eat willingly, fed in amounts that will maintain a good body condition score. This might be enough to control the signs (of course accompanied with the other modifications needed, see above). Cats already eating canned diets or cats that refuse anything other than dry food might benefit from a therapeutic urinary diet.
References
1. Defauw PA, Van de Maele I, Duchateau L, et al. Risk factors and clinical presentation of cats with feline idiopathic cystitis. J Feline Med Surg. 2011;13:967–975.
2. Cameron ME, Casey RA, Bradshaw JW, et al. A study of environmental and behavioural factors that may be associated with feline idiopathic cystitis. J Small Anim Pract. 2004;45:144–147.
3. Buffington CA, Westropp JL, Chew DJ, et al. Clinical evaluation of multimodal environmental modification (MEMO) in the management of cats with idiopathic cystitis. J Feline Med Surg. 2006;8:261–268.
4. Stella JL, Lord LK, Buffington CAT. Sickness behaviors in response to unusual external events in healthy cats and cats with feline interstitial cystitis. J Am Vet Med Assoc. 2011;238:67–73.
5. Markwell PJ, Buffington CA, et al. Clinical evaluation of commercially available urinary acidification diets in the management of idiopathic cystitis in cats. J Am Vet Med Assoc. 1999;214: 361–365.
6. Gunn-Moore DA, Shenoy CM. Oral glucosamine and the management of feline idiopathic cystitis. J Feline Med Surg. 2004;6:219–225.
7. Kruger JM, Lulich JM, Merills J, et al. A year-long prospective, randomized, double masked study of nutrition on feline idiopathic cystitis. In: Proceedings from the American College of Veterinary Medicine Forum 2013. Accessed on line on February 1st, 2015.
8. Wei A, Fascetti AJ, Villaverde C, et al. Effect of water content in a canned food on voluntary food intake and body weight in cats. Am J Vet Res. 2011;72:918–923.