Testing, testing: how much preventative care and screening do we need?

Important note: as they say, I’m not a doctor (well, not an MD; my philosophy PhD really doesn’t count here). We all read, talk to people and make our own decisions about what to do based on our particular values and needs and goals and bodies and finances and time. So this isn’t advice, much less a medical recommendation. (Not that you’d think so, but I figured I’d say it anyway).

Okay, that said: I went to the gynecologist this week.

I was there to deal with some menopausal symptoms (a topic for another blog post). During the appointment (my first with this doctor), she reeled off a big list of questions about screening, including mammograms, paps, etc. I tend to be a bit behind schedule according to American (but not necessarily other country) standards for various types of health screening. In this country, there’s a lot of variation among individual practitioners about screening, and they are sometimes at odds with national professional scientific panel recommendations (e.g. for mammography, see here the US Preventative Services Task Force recommendations).

My previous internist and I got into a heated argument about screening– she wanted yearly mammograms for me (luckily I have no family history of breast cancer nor is it likely I have genetic markers for it) and in response I cited the USPSTF results. She replied, “well, I don’t agree with them”. I asked what evidence she had to contravene those results. She had none. I changed doctors a bit later.

It turns out that I have some company in being resistant to and skeptical of many (although not all) medical screening. Barbara Ehrenreich (one of my author-essayist heroes; her classic book Nickeled and Dimed forever changed my view of labor justice) has published a new book called Natural Causes: An Epidemic of Wellness, the Certainty of Dying, and Killing Ourselves to Live Longer. I recently read an essay excerpt from the book here, which definitely makes me want to read the whole book (when I do, I’ll post a review).

Ehrenreich is reacting to two trends she sees:

1. the technological new-toy enthusiasm in the medical establishment which pushes us to be examined, measured minutely, recorded and treated, just in case the barely registerable potential abnormality that we’ve been informed of will rise up to plague us;
2. the identification of this tech-heavy but not obviously therapeutic process with normal health maintenance; resistance is seen as irresponsible and maybe even irrational.

I really like this example she gives of a medical encounter that perfectly illustrates 1):

I was struck by the professionals’ dismissal of my subjective reports—usually along the lines of “I feel fine”—in favor of the occult findings of their equipment. One physician, unprompted by any obvious signs or symptoms, decided to measure my lung capacity with the new handheld instrument he’d acquired for this purpose. I breathed into it, as instructed, as hard as I could, but my breath did not register on his screen. He fiddled with the instrument, looking deeply perturbed, and told me I seemed to be suffering from a pulmonary obstruction. In my defense, I argued that I do at least 30 minutes of aerobic exercise a day, not counting ordinary walking, but I was too polite to demonstrate that I was still capable of vigorous oral argument.

There are a bunch of questions that she raises here, and they are issues that I think about a lot in my professional life (as a public health ethics person) and in my personal life (as an aging, active, curious person). One of them is this: if I don’t have any symptoms, does it serve me to engage in high-tech explorations of my systems in search of something that looks amiss to the machine?

This is of course a very hard and controversial question. The whole issue of screening for diseases and risk factors and conditions and genetic markers for people who are asymptomatic is a huge area of health research for a lot of fields (mine included). I did find this interesting systematic review of meta-analyses and randomized trials (this means they looked at a ton of data at several levels using very fancy methods). It asks a very straightforward question: does screening for disease save lives in asymptomatic adults?

The straightforward answer is: for the most part, no. Here’s what their abstract conclusion says:

Among currently available screening tests for diseases where death is a common outcome, reductions in disease-specific mortality are uncommon and reductions in all-cause mortality are very rare or non-existent.

What does this mean? I can get various kinds of screening for diseases– mammograms, colonoscopies, blood chemistry, imaging and other tests for cancers, heart diseases, type 2 diabetes, etc. The researchers asked two questions:

1. How likely are these individual screening tests to reduce my risk of dying from that particular disease?
2. How likely are these individual screening testing to reduce my risk of dying for any reason?

In the case of 1), they did see some reductions in disease-specific mortality risk for four tests (including mammography under some protocols, and two less-invasive-than-colonoscpy tests for colorectal cancer). But they didn’t find those reductions for the other 15 screening tests they looked at (I won’t list them here, in part because their results are more robust for some than others based on availability of evidence). However, here are a few nuggets I found that put them in Ehrenreich’s camp: