Daisy’s renal function

I took Daisy, our 15-year-old cat, to the vet to have her long sharp front claws trimmed. She had taken to jumping up on the bed every morning, expressing her desire for food and attention by scratching my forearms hard enough to make them bleed. The vet recommended a geriatric health screen. Daisy was kept in the clinic all day for blood and urine tests, and the results showed that her renal function was somewhat impaired. I agreed to another blood test to assess the extent of the problem.

Renal (kidney) failure is very common in older cats. The many possible causes include urinary infections and ingestion of poisons. In many cases no specific cause can be found, though I wonder if processed food is implicated, for example cats fed on dry biscuits may get too much salt and not enough water. Our own cats certainly love dry biscuits, but I have always limited their intake, and fed a mixed diet with moist canned food and fresh meat, poultry or fish. The symptoms of renal failure can include increased thirst, increased urine volume, loss of appetite and weight, vomiting, diarrhoea, and general weakness. It is sometimes associated with other conditions such as anaemia, hypertension and hyperthyroidism.

Although diet is an important aspect of management, according to my reading there is some controversy around this. The standard prescription foods are low in protein, but some experts recommend feeding plenty of protein from fresh high-grade animal sources. Medication may delay progression of the condition. Adequate fluid intake is important, and severe acute cases may need parenteral fluids. Some specialised centres even offer renal dialysis and kidney transplantation.

Daisy’s second blood test showed that her renal function was “borderline”. She appears very well and has none of the symptoms listed above. After a long discussion with the vet we agreed not to initiate drug treatment or a special diet at this time.

I was about to leave the clinic when I checked on her claws and found that they had forgotten to trim them, so she was taken back to have that done. It had turned out a very expensive manicure; I could have tried to do it myself at home, though I am sure she would have scratched me.

Whether investigation of Daisy’s renal function has been worthwhile, only time will tell. Both in veterinary and in human medicine, screening for disease has pros and cons. Sometimes it does pick up a serious condition for which early treatment is desirable and even life saving. But modern tests are so sensitive that they often detect very minor abnormalities, prompting further investigations which can involve a great deal of discomfort, anxiety and expense and usually prove to have been unnecessary. On several occasions I myself have had blood results, X-Rays or biopsies reported as “borderline” or “suspicious” that eventually turned out to have been false alarms.

Daisy lying back

Too much medical measurement?

Following a couple of recent high blood pressure readings I had a 24-hour monitor test which was reported as normal – a great relief. I don’t know whether my various small lifestyle changes had made a difference, or whether the previous reading was the result of ‘white coat hypertension’ at the clinic, or of an inaccurate machine at home. I’ll keep an eye on the situation – and continue the improvements in diet and exercise, and with following the mantra NO NEED TO RUSH.

I am uncomfortably aware that many other people are taking long-term, even life-long, hypotensive medication on the basis of just one single high reading without having the 24-hour test – either because this wasn’t suggested to them, or because they couldn’t afford to pay for it.

Many medical screening tests besides blood pressure checks are advocated today. Occasionally, they detect an early case of serious disease which can be successfully treated. This life-saving benefit for a few people has to be balanced against the downside for many others – a widespread increase in health-related anxiety among the ‘worried well’ and the practice of treating risk factors and borderline abnormalities in the same way as established diseases, although in the majority of cases they might never have progressed to cause symptoms. Sometimes the treatments, or even the tests themselves, cause harm. In my own circle, for example, one woman recently developed renal failure attributed to ‘preventative’ medication prescribed on dubious grounds, and another suffered a bowel perforation during a ‘routine’ colonoscopy which had revealed no abnormality.

Many experts, quoting statistics from studies on large populations, claim that the benefits of screening tests and preventative interventions outweigh their risks. Others disagree. Political and financial factors are often involved as well as strictly medical ones. For example, the recent books Pharmageddon by David Healy and Bad Pharma by Ben Goldacre reveal the techniques through which drug companies covertly encourage doctors to prescribe. And although most healthcare professionals are sincerely motivated to put the good of their patients ahead of personal gain, they may be unconsciously influenced by the fact that careers can be advanced and money can be made by promoting screening programs or by broadening the definitions of pathology.

Over the years, I have been diagnosed with several different borderline conditions myself. I had treatment for some of them, and others I chose to ignore, but whether these were the ‘right’ decisions I may never know.