March 7, 2007

More Evidence that Common Over-The-Counter Pain Pills are Toxic to the Kidney

This week's Diabetes in Control newsletter reports on a new study that finds that daily use of common painkillers including Tylenol (acetaminophen), Ibuprofen (Motrin) and even aspirin raise the incidence of high blood pressure very significantly.

Here is what "Diabetes in Control" wrote in their summary of this study, published in February in Archives of Internal Medicine (and hence, alas, not available in full text to us proles without subscriptions.)

"John P. Forman, MSc, MD, of Brigham and Women's Hospital and Harvard Medical School, Boston, and colleagues followed a total of 16,031 male health professionals (average age 64.6 years) who did not have a history of high blood pressure. The men were asked in 2000 and again in 2002 about whether and how often they used three types of pain relievers: acetaminophen, NSAIDs and aspirin. They were also asked to report if their physician had diagnosed them with hypertension.

"Over four years of follow-up, 1,968 men developed hypertension. Compared with men who did not take analgesics, those who took acetaminophen six or seven days a week had a 34% higher risk of hypertension. Those who took NSAIDs six or seven days a week had a 38% higher risk and those who took aspirin six or seven days a week had a 26% higher risk."

High blood pressure is often the very first sign of kidney dysfunction, though doctors continue to treat high blood pressure as "idiopathic" (doctor speak for "we have no clue what causes it.")

Coming on top of an earlier study which found that there is clear-cut relationship between your lifetime dose of acetaminophen and NSAID painkillers like ibuprofen and your likelihood of suffering total kidney failure (End Stage Renal Disease or ESRD), this should be a wake-up call to anyone who still pops a pain pill any time they have the slightest bit of discomfort.

How many pain pills are damaging? According to this study published in the New England Journal of Medicine, a lot less than you might think:

"When persons who took an average of 0 to 104 pills [of acetaminophen] per year were used for reference, the odds ratio of ESRD was 1.4 (95 percent confidence interval, 0.8 to 2.4) for those who took 105 to 365 pills per year and 2.1 (95 percent confidence interval, 1.1 to 3.7) for those who took 366 or more pills per year, after adjustment for race, sex, age, and intake of other analgesic drugs."

What this means in English is that taking one Tylenol pill every three days throughout the year is enough to give you a significantly increased risk for ending up on dialysis. And remember, this finding applied to a normal population, not people with diabetes who already have an increased risk for kidney failure.

The study also found "When persons who had taken fewer than 1000 pills containing acetaminophen in their lifetime were used for reference, the odds ratio [for developing end stage renal disease] was 2.0 (95 percent confidence interval, 1.3 to 3.2) for those who had taken 1000 to 4999 pills and 2.4 (95 percent confidence interval, 1.2 to 4.8) for those who had taken 5000 or more pills."

This means that you are twice as likely to end up on dialysis if you take between 1000 and 4999 Tylenol or acetaminophen pills during your entire lifetime!. That's slightly over ten bottles of pills. Over your lifetime!

The study also found "A cumulative dose of 5000 or more pills containing NSAIDs was also associated with an increased odds of ESRD (odds ratio, 8.8)." This refers to drugs like ibuprofen and naproxen (sold as Motrin and Anaprox.)

The NEJM article did not find a relationship between lifetime dose of aspirin and kidney failure, but it's worth noting that the new study did find that taking aspirin daily did go along with the development of high blood pressure.

Looks like it's time to stop popping "vitamin I" every time you feel a little sore.

Save the painkillers for when you are really in pain and then if you must take a pill, take the smallest pill that will get the job done. I find that one 325 mg regular strength Tylenol is all I need when I have serious nerve pain from my ruptured disc. Taking more does not increase the relief. But I also find I have to hunt for the regular strength version of the drug, since the pharmacies clearly believe "more is better" and most of the bottles on the pain reliever shelf are "extra strength" versions that contain at least twice as much drug per pill.

If you require long term pain treatment for a chronic condition like arthritis, raise the issue with your doctor of whether there is some other class of drugs available that might be less dangerous for your kidneys. I did this when I was having a rough time with nerve compression in my frozen shoulder and ended up using Tramadol to help me sleep. Tramadol is usually considered a heavy duty drug, but it worked, and when the pain abated after six weeks I had no trouble stopping it. I did take Tylenol when the pain got really bad during the day, since it is very effective for nerve pain, but I tried to limit myself to no more than 2 pills a day, and less if I could, because I knew it was going to be a while until the problem resolved and I really like having functional kidneys.