Monday, November 29, 2010

Does Your Medicine do Anything?

To go along with the earlier post on medical experimentation, and its somewhat dubious reliability:  The Crumbly Edifice of Modern Medicine , we are going to present some more interesting information from one of my favorite prognosticators of existential finality: Robert Hanson.  Mr. Hanson has a blog of his own, Overcoming Bias, and you will find a variety of rather unique ideas there in addition to a like to the paper quoted below.

Fear of Death and Muddled Thinking – It Is So Much Worse Than You Think

Robin Hanson, Department of Economics, George Mason University†, August 2005

In another study
Correlations-in-the-world studies see many apparently large influences on health, including age, gender, exercise, social status, urban location, smoking, sleep, and even church attendance. Gender, exercise and social status, for example, can change lifespans by ten to fifteen years or more (Lantz, House, Lepkowski, Williams, Mero, & Chen, 1998). When one looks at medical spending, however, the usual finding in such studies is no effect. When comparing nations or counties or individuals, people who get more medicine have no significant difference in health when compared to people who get less medicine.
For example, Jonathan Skinner and John Wennberg looked at five million Medicare patients in about 3500 hospital service areas in 1990. They looked to see if people died less in areas where, during the last six months of life, Medicare spent more on treatment. After controlling for age, sex, race, median income, poverty, education, urbanization, and initial health limitations, Skinner and Wennberg found that the average effect of spending $1000 more was somewhere between increasing lifespan by about five days and decreasing it by about fifteen days.  Areas that kept patients in the intensive care unit one more day on average
In the late 1970s, most of 5816 non-elderly adults6 from six U.S. cities were randomly assigned for three to five years to one of two situations. Either they had free health care, or they had to pay a substantial fraction (ranging from 25 to 95 percent) of their health care costs. People with free health care had more doctor and hospital visits, and those with free care spent about 75% more than those who paid nearly full price. While this sample was too small to see effects on death rates, the plan was to look at a general health index based on over twenty health indicators (Newhouse & Group, 1993).
What did they find? The bottom line: no significant difference in general health was seen between those with more health care and those with less. And since this was a randomized, but not blind, clinical trial, this no-effect result includes any health benefits that people get from feeling that they are being cared more for via free care. This suggests that free care would look even worse without such placebo effects.
If medicine for treating individuals is not quite the miracle we have heard, does public health make up the difference? Have not we all heard how the introduction of modern water and sewer systems greatly improved our ancestors’ health? Well, a century ago the U.S. cities with the most advanced water and sewer systems had higher death rates than the other cities. Also, we can look today at how the death rates of individual households correlates with the water sources and sewer mechanisms used by those households. Even in poor countries with high death rates, once we control for a few other variables like social status we usually find that water and sewer parameters are unrelated to death rates (Lee, Rosenzweig, & Pitt, 1997)…
Well we must live longer now for some reason, right? Yes, and in fact in the developed nations it seems that age specific death rates have fallen at a relatively  steady exponential
But the fact is that we just do not know why we now live so much longer.
Most of the obvious theories have serious problems, you see. For example, exercise, smoking, social status, and urban living appear to have large effects on individuals. But the time trends for exercise, urban living, and smoking have been in the wrong direction – those trends would predict decreasing lifespan. And since social status is usually thought to be relative to contemporaries, it is hard to see how average social status can increase with time.
Finally, while the biggest advances in nutrition, medicine, and public health seem to have occurred during the first two thirds of the twentieth century, death rates have fallen just as fast during the last third of the twentieth century. Perhaps some new influence rose in importance just as those other influences became less important, but if so it seems a remarkable coincidence that the total rate of improvement has remained pretty steady.
Another problem would be various “free-loader” issues.  If you have a population of 1,000 people and all of them take the polio vaccine.  If one person joins this population, are there health benefits increased or decreased by taking the vaccine.  It is very similar to the issue of avoiding conflagration type urban fires (Ms. O’Leary’s Cow and Chicago) where the cost benefits to fire protective measures can be negative when the other buildings in the neighborhood are built to modern fire code standards.
The net effect would be to make it more important to live within a relatively healthy society, than to live a healthy life style.
There are probably a number of factors that help increase the life span of individuals today, but their uneven distribution along with the uneven distribution of various negative factors makes separation difficult.    The wide spread use of antibiotics, the knowledge of bacterial/viral infection and more effective avoidance strategies,  a greater overall calorie intake, and decreased physical stress (physical labor) on the work force would all be likely factors that would come into play. 

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