I typically recommend some form of laboratory health screen for my older, feline patients. To justify the expense and stress associated with collecting samples, I typically point to the benefits of detecting disease early, the ability to pick up trends before overt abnormalities develop, and having a baseline to which we can compare should the cat become sick in the future. The details of exactly what might be included depend on the cat’s age, lifestyle, and health history.
Along the same lines, the American Animal Hospital Association (AAHA) and American Association of Feline Practitioners (AAFP) came out with Feline Life Stage Guidelines in 2010, which stated that cats seven years of age or older should receive a complete blood cell count, blood chemistry screen, urinalysis, fecal exam, and possibly screening for feline immunodeficiency virus/feline leukemia virus. Cats who are eleven years of age and older should also have their blood pressure and thyroid levels checked.
Despite recommendations like these being widely adopted throughout the veterinary profession, we really had very little (if any) scientific evidence of the benefits of screening. In fact, the AAFP-AAHA guidelines actually stated, “specific data documenting benefits are not available” and that “more robust incidence data is needed to develop firmer recommendations.” Well, that data is now available.
In a study published in the January 2013 issue of the Journal of Feline Medicine and Surgery, one hundred cats aged six years and above underwent physical examination, blood and urine analysis, blood pressure measurement, ophthalmologic exam, and tear production tests. The owners of all of the cats thought they were healthy and the researchers concurred based on a comprehensive health questionnaire. The goal of the study was to determine the incidence of abnormalities in middle aged and older cats and to investigate the suitability of laboratory reference ranges for this group of animals.
The following problems were found:
- Increased blood pressure — 8 cats
- Swollen lymph nodes under the jaw — 32 cats
- Gingivitis — 72 cats
- Heart murmur — 11 cats
- A palpably enlarged thyroid gland — 20 cats
- High blood creatinine levels — 29 cats
- High blood sugar — 25 cats
- High thyroid hormone levels — 3 cats
- Positive status for FIV — 14 cats
- The presence of crystals in the urine — 41 cats
- Abnormal levels of protein in the urine — 2 cats (25 others had borderline levels)
The researchers made sure to point out that all of these abnormalities were unlikely to be clinically relevant; some were probably due to the fact that the same reference ranges apply to cats of all ages. What we need are reference ranges that are more specifically tailored to different populations of cats.
Despite the study’s limitations, it does an excellent job of demonstrating that apparently healthy middle aged and older cats may not be doing as well as we think.
Dr. Jennifer Coates
Routine health screening: findings in apparently healthy middle-aged and old cats. Paepe D, Verjans G, Duchateau L, Piron K, Ghys L, Daminet S. J Feline Med Surg. 2013 Jan;15(1):8-19.