Thursday, June 30, 2016
The Demise of the "5th Vital Sign"
The American Medical Association came out two days ago and said that they were dropping the pain as the fifth vital sign movement because it encouraged opioid overprescribing. Even more interesting is that I did not get the news from the AMA (I am a 30 year member) but from the Pain News Network. The only stories that I could Google the next day was about the AMA defending its position against attacks from pain societies and organizations who want to maintain what I would describe as a liberal approach to opioid prescribing as the best way to approach pain. My term liberal is meant to connote a political position with no basis in science and the lack of science started in 1998 with the pain as a 5th vital sign approach. In 1996, the President of the American Pain Society declared pain as the Fifth Vital Sign. In the year 2000, the Joint Commission (then JCAHO) launched a pain initiative that described the 10 point pain scale as a "quantitative approach to pain."
I don't know if quantitative analysis is still a prerequisite for medical school, but this is a reason why it still should be. In quantitative analysis, the task is to measure chemical concentrations accurately and reproducibly. To use a quote from my old analytical chemistry text (1): "Qualitative analysis is concerned with what is present, quantitative analysis with how much is present." The ability to do this is often a major part of the grade for that course. Since the chemical composition in the samples are known - they should be determinable with precision. In some cases, a lack of accuracy can reflect problems with the analytical technique if there are widespread variations in the results. This is a true quantitative approach. Asking a person to rate their pain on a 10-point scale is not. Pain is a subjective experience influenced by a number of variables including whether the pain is acute or chronic, emotional state, the presence of an addiction, and personal biology affecting pain perception. It is not a quantitative assessment. It is as obvious as asking someone where they are on the 10-point scale and being told they are a "14". There are a lot of potential messages with that statement, but none of them involve an accurate measurement of pain. A quantitative scale has no implicit meaning - it is supposed to be a known measurable quantity no matter what.
From a medical perspective, there is also no better example of the adverse consequences of widespread screening for a problem. Chronic pain varies with age and other demographic factors. Epidemiological surveys show widely variable numbers of people with chronic pain, but some suggest an average is about 25% of the population and 10% of the population with pain that has some secondary disability. While there are no good ways to estimate the optimal amount of opioid needed to treat pain in a population, current data suggests that the US is the largest consumer of prescription opioid drugs in the world. For example, the US has 5% of the world's population and Americans use 55% of the world's supply morphine and 37% of the world supply of fentanyl. By contrast 80% of the world population uses 9.9% of the morphine and 19.7% of the world's fentanyl. The United States is clearly at the top in terms of opioid consumption.
Clinical trials have also shown that opioids are moderately effective for some forms of chronic pain and no more effective than non-opioid medications. The screening approach to chronic pain is clearly associated with overexposure to opioids, widespread availability of illicit sources of opioids, and an epidemic of overdose deaths. The idea that rapid assessments can be made with rapid qualitative screening by anyone also eliminated pain specialists as gatekeepers in the decisions about who would receive treatment with opioids for chronic noncancer pain.
In the opening days since the AMA statement, it appears that political forces are lining up to maintain the status quo. The idea that the AMA has to defend their position seems like pure rhetoric to me. How about the American Pain Society defending the original statement in the context of everything that has happened since? Despite defensive statements about how opioid prescribing was increasing before the position was adopted - the hard data suggests that it was associated with a major inflection point in opioid consumption in the USA.
The policy debate on this simple statement has far reaching effects for health policy in the United States. At every level in today's health care system there are groups of managers/administrators who have set themselves up to monitor various measurements and hold somebody accountable. I doubt that they know the difference between quantitative or qualitative measurements any more than the people who proposed that a subjective pain scale was somehow a quantitative measure.
I doubt that any one of them ever took a class in Quantitative Analytical Chemistry.
George Dawson, MD, DFAPA
1: James S. Fritz and George H. Schenk. Quantitative Analytical Chemistry. Second Edition. Copyright 1969 by Allyn and Bacon, Boston, p 3.
Pain scale graphic downloaded from Shutterstock per their standard license on June 29. 2016.