Something Not Unlike Research

Screening is a process, not a test

post by Bill Gardner

From @AaronECarroll, a pointer to a letter from an oncologist/patient in the current Archives of Internal Medicine.

Six years ago, after celebrating my 50th birthday, I chose to begin an annual ritual of having my prostate-specific antigen (PSA) level checked... One year later, I had my PSA level checked again; it was 2.5 ng/mL... I chose to be an informed patient and got an opinion from leading medical, surgical, and radiation oncologists throughout the country. In the end,... I chose surgery, viewing the risks as small and the benefits as great. Fast forward 5 years: cancer free. However, as a result of the surgery, my right arm and right leg are permanently weak, with this deficit appearing immediately after surgery. The reasons for this outcome are unclear. My PSA level remains 0, but my daily 5-mile jog is no longer possible. 

He is an example of the problem that has led many to question the wisdom of PSA screening: death is not necessarily quick or certain if you have prostate cancern, and the cost of being "cancer-free" is often very high. The oncologist continues,

Where am I now on the PSA dilemma in light of the recent US Preventive Services Task Force recommendations? It is clear that prostatectomy results in a very high chance of 20-year prostate cancer–specific survival, but even when the procedure is performed by an expert urologist, it can also result in significant rates of sexual, bladder, and bowel dysfunction and other less common adverse effects, such as my weakness. Active surveillance with longitudinal PSA tests and physical examination is associated with very low rates of bowel, bladder, and sexual dysfunction and has a high probability of correctly identifying when to move from surveillance to treatment. If I could do it all over again, I would not undergo the surgery; instead, I would opt for active surveillance. 

Emphasis mine. He is not regretting the decision to be screened, he is regretting the decision to have immediate surgery, instead of closely monitoring the cancer and having surgery when he clearly needs it. Without further study, we can't say with confidence that patients like the oncologist would do better with active surveillance. Moreover, he might not have been able to endure the concern about cancer. The point, though, is that the screen result was just information. What mattered is what the patient and his doctors decided to do with the screen.

A screen in and of itself provides little benefit: it only benefits the patient if it leads to a beneficial treatment. In a manuscript under review, I discuss how the potential benefit of depression screening programs is largely wasted because the clinical processes that convey patients from positive screen results to successful treatments break down at myriad points. Lots of mundane clinical process issues -- for example, does the doctor have time to check the EHR for a screen result before talking to the patient -- affect the results of screening as surely as does the biochemistry of the screening assay. I do not think that it has been sufficiently stressed that, as Aaron said on Twitter, "Screening is a process, not a test." 

The doctor and the patient: That relationship is so over

post by Bill Gardner

Robert Truog has a magisterial NEJM review of the evolution of medical ethics and the evolving relationship between patients and doctors. It is natural that he would structure the review in a discussion of this relationship because, as he notes,

The relationship between patients and doctors is at the core of medical ethics, serving as an anchor for many of the most important debates in the field.  

In that relationship, the doctor has the duty to try to learn what the patient needs and what the patient wants, so that she can serve as the patient's agent to promote his well-being.

But increasingly, a longterm relationship between a patient and a doctor isn't the primary context in which care happens.

• Many patients are seeking care in non-traditional settings: an urgent care in a WalMart may be the future of primary care. Even if patients would prefer an ongoing relationship with a specific provider, it may not fit the time or financial constraints on their lives. This isn't just an issue for the poor. I live and work in two cities 2400 km apart, and I meet many people with similar lives. It doesn't make sense for me to try to get care from one physician.
• Many primary care practices are not structured to facilitate sustained one-to-one care relationships. In many practices, the first doctor who is free grabs the chart at the top of the rack, and the next patient on the list is called. Getting your primary care from a single PCP is increasingly a high cost 'boutique' alternative.
• Care of any complexity involves a team of disciplines, including nurses, pharmacists, and many technicians. The latter are critical to successful care, and are not failed attempts at being doctors. Nurses are, often, the leaders of follow-up care and the central channel for communication with patients.
• The amount of medical data / patient in modern health systems increases exponentially, and for patients of any complexity it often exceeds the ability of a physician to usefully synthesize it.
• We are beginning to see primitive dialogues between robots and patients as important channels for medical information.

This means that knowledge of the patient is not held by a clinician, but is difused across many persons and places in the health care system. All too often this has the unfortunate consequence that no single health care provider has responsibility for the patient's well-being, and that elements of knowledge about the patient are disconnected, and cannot be assembled to guide action. Bioethicists and many others have viewed the difusion of personal relationships between doctors and patients as threats to the quality of care. Which they may well be, but the world of close relationships between the country doc and his patients, if it ever existed, is not coming back. 

So how should we reframe bioethical discussions? I think we should stop imagining health care communication as occurring primarily on an interpersonal channel between the doctor and the patient. Knowledge about the patient, if it is anywhere, is in the system, so we should begin to think through what it would mean to have health care systems be responsible to know about what patients need and want, and to serve as the patient's agent.

Many issues arise when you see care as the job of a system.

1. If the system is responsible for your care, then arguably your detailed health information ought to be available to any provider in the system you happen to contact. Care is likely better if information can flow freely within a health care system -- for example, your gastro-enterologist ought to know if you are taking an antidepressant. What are the limits on the appropriate sharing of knowledge within an organization? How much control can/should patients have over intra-organizational flow of personal health information? 
2. Which patients is a health care provider responsible for? Every subscriber to a system? How do you hold individual providers accountable if every provider is responsible for every patient? 
3. Traditional health care is reactive to patient demand: care is supplied to the patients who come in an ask for it. But a prevention-oriented health care system can reach out and prompt patients to get health care services that the system infers that they might need. What are the proactive obligations of a system? What are the ethical constraints on a system? Should patients have to opt-in to preventive outreach?  
4. A system has clout that an individual doc does not. A children's hospital can lobby to improve the diet in the local school lunches. Should it, or is this the prereogative of the parents in the neighborhood?
5. A smart system can interact with patients carrying smart phones or tablets in lots of places outside clinic walls. Such interactions can be used to get far more health information on patients than can be gathered by a doc in annual 15 minute office visit. How do you handle consent and confidentiality in health conversations that may be occuring in public?

The extraordinary value of health care research, and our responsibility to future generations

post by Bill Gardner

Harold Pollack commented on a classic paper by Kevin Murphy and Robert Topol that changed how I see the world (see also Austin Frakt). I want to comment on what I have found in the paper, and a moral problem it poses.

Murphy and Topol ask, are we getting anything from the GDP (now 17%) we consume in health care, and from the billions we invest each year in medical research ($31.2B for the NIH alone)?

The answer is YES:

We calculate (i) the social value of increased longevity that took place from 1970 to 1990 and, (ii) the social value of potential future progress against various major categories of disease. The historical gains from increased longevity have been enormous, on the order of $4.4 trillion annually from 1970 to 1990. The reduction in mortality from heart disease alone has increased the value of life by about $2.3 trillion per year over the 1970 to 1990 period. The potential gains from future innovations in health care are also extremely large. Eliminating deaths from heart disease would generate approximately $75 trillion in economic value while a cure for cancer would be worth $73 trillion. Even a modest 1 percent reduction in cancer mortality would be worth about $775 billion. Unless costs of treatment rise dramatically with the application of new medical knowledge, these estimates indicate that the social returns to investment in new medical knowledge are enormous.

(I have converted all the estimates from $1992 in the original text to $2010, using the BLS calculator.) In brief, M & T argue that in the recent years of science-driven improvements in health care based in new medical knowledge have added many thousands of life-years to our collective longevity. Valuing these life-years in dollars we see that, among other innovations, "The reduction in mortality from heart disease alone has increased the value of life by about $2.3 trillion per year over the 1970 to 1990 period." For a benchmark, US 2010 gross domestic product is about $14 trillion. The message is that despite enormous waste in our health care spending, we are nevertheless getting an extraordinary return from our investments in science-based care. Although nothing is certain, it's reasonable to expect that continuing to invest in medical research will continue to bring significant returns. 

As Harold describes, it's a breathtaking paper. Murphy and Topol are saying that thanks to science-driven health care our economy is producing not just tomatoes and Camaros, but also additional years of life. These additional years have stupendous value, but somehow we do not see it. The calculation is something like what the physicists did when they weighed the universe, found that there is vastly greater mass present than can be accounted for by ordinary 'visible' matter, and inferred that we are swimming in dark matter. There is a wonder in that finding, but there is also wonder in how they did it (they weighed the universe? HOW??). 

So why is that value is hard to see? First, longevity is intangible. Second, most medical research is not particularly valuable. It's like the shipwrecked man putting notes in bottles and throwing them into the sea. The one that is picked up is extradorinarily valuable, the rest are just litter. But most importantly, the benefits of the investments in research that are valuable are realized over a long time span. It often takes decades to get a finding from the lab to the bedside. We are currently enjoying the benefits of investments in the development of cardiovascular disease treatments that were made decades ago. 

And this leads to an ethical problem. The older you get, the less you have to gain from additional medical research, particularly in basic science. A discovery in fundamental biology made tomorrow will probably not affect the medical care that will be available in my life time. However, my generation is reaping extraordinary benefit from previous generations having diverted some of their savings to an investment that probably had little material benefit for them. (A small consequence of the M & T paper is that -- yet again -- I owe my father's and mother's generation a debt of gratitude, because they made this investment for me even though they were, collectively, much poorer than I am.) If we do not continue to spend on medical research, future generations will get at least as much longevity as we currently have, because medical knowledge is not consumed. But they may not experience the same gains in longevity that they would have gotten if we had, as our fathers and mothers did, diverted some of our consumption to research. We see this happening now with the NIH budget, and it will get worse. 

There is a difficult argument here about justice for future generations. Do we (can we?) owe anything to people who do not even exist? Moreover, are we obligated to forgo our consumption, so that these unknown future persons will live longer than we will? Yet it nevertheless it feels wrong not to invest in a better medical future. It's as if we had been rescued from drowning, but in doing so the boat that rescued us was lost. We are asked to make a contribution to replacing it, so that others can be rescued in the future. We have no plans to go out on the water again. And so we decline.

This problem is everywhere. What is the duty of the elderly to pay for the education of toddlers whose maturity they will never see? Do people living now have to care if the carbon they emit now increases radiative forcing for the next thousand years?

Americans love Canada and other social democracies

post by Bill Gardner

Mitt Romney:

I want you to remember when our White House reflected the best of who we are, not the worst of what Europe has become.

The worst of what Europe has become refers, I think, to European social democracy. I have to imagine that he shares a similar concern for those of us living in Canada under similar institutions. (I have to imagine because I can't find a quote: a "Romney Canada" Google search returns stories about his driving to Canada with his dog strapped to the roof.) Newt Gingrich, however, doesn't think Romney goes far enough in his disdain for Europe, and accuses Romney of pursuing "European socialist ideas." Rick Santorum apparently believes that European cultures are dying. 

Interestingly, though, Americans seem to like these places. The Gallup poll reports that 75% of Americans have a positive view of France, 86% for Germany, and 90% for Great Britain. Among non-European countries with social democratic institutions, 83% of Americans have a positive view of Japan, 93% have a positive view of Australia, and an astonishing 96% percent have a positive view of Canada. 

Understanding DALYs

post by Paul Kelleher

Cost-effectiveness analysis (CEA) compares, you guessed it, costs with benefits. Costs are typically conveyed in monetary terms. Benefits are usually conveyed in terms of either QALYs or DALYs. QALYs are quality-adjusted life years. DALYs are disability-adjusted life years. QALYs have been around since the 1970s (as I understand it), whereas DALYs are a more recent innovation. In 1994, Christopher J. L. Murray, then of Harvard University, introduced DALYs in his paper "Quantifying the Burden of Disease." Murray then went on to the World Health Organization (WHO), where DALYs were used in the controversial attempt by WHO to rank the equity and effectiveness of the world's national health systems. Both QALYs and DALYs are used widely today as the units of benefit-measurement in cost-effectiveness analyses.

This week I've spent a lot of time reading and thinking about CEA, and I've encountered quite a bit of confusion in the literature on how DALYs should be understood. For example, I was looking at a paper entitled "The Economics of HIV/AIDS in Low-Income Countries: The Case for Prevention" which reports CEA results in terms of the cost per "loss of DALY averted." This implies that, whatever DALYs are, you should want more of them rather than fewer (i.e. you want to avert their loss). This understanding of DALYs is made explicit in "Using Cost-Effectiveness Analysis for Setting Health Priorities," a report by the Disease Control Priorities Project (which appears affiliated with the World Bank and WHO): 

In cost-effectiveness analysis, the DALY represents the number of years of disability-free life that would be gained from a particular health intervention—yielding a cost per DALY where cost data are available or can be inferred. Gaining a DALY through a health intervention reduces the burden of disease; it is the same as averting the loss of a DALY. 

Compare this understanding of DALYs with that stated in Disease Control Priorities in Developing Countries by Dean T. Jamison, who worked on WHO's Global Burden of Disease Project and continues this work at the at the University of Washington's Institute for Health Metrics and Evaluation (which Chris Murray now directs):

Disability-adjusted life years (DALYs) are a variant of QALYs in that they measure the losses from disability or premature death; a CEA will determine which interventions maximize QALYs or minimize DALYs.

So which understanding of DALYs is correct? Do we want to maximize DALYs (i.e. avert their loss) or do we want to minimize them (i.e. praise their loss)? The answer is that Jamison is right: DALYs are to be minimized (and their loss praised). But how could those others, who work with DALYs all the time, get it so wrong? Let me try to explain.

Both QALYs and DALYs are designed to integrate considerations of longevity and quality-of-life. For example, I generate 1 QALY for every year I live in full health. The number of QALYs one generates is calculated by multiplying the length of time (measured in years) by a "utility weight" which places one's health status on a scale of 0 to 1 where 0 is as bad as death and 1 is full health. So if I live 2 years in a health state that has a utility weighting of 0.8 (perhaps I have mild lower back pain), then I am said to generate 1.6 QALYs (2 x 0.8) over that time span. Given this understanding, one obviously wants more QALYs rather than fewer, since more QALYs correlates with more years lived in good health.

QALYs are therefore used to measure healthy years lived. DALYs, by contrast, are used to measure healthy years lost. That is, DALYs measure the gap between the number of healthy years one in fact lives and some normative ideal of how many healthy years equates to full health over a lifetime. The normative ideal of longevity is set using the world's longest actual life-span, which is set by the Japanese. The normative ideal of health-related quality-of-life is a trickier subject that I want to pass over here. The important thing is that it is stipulated by DALY-users that full health for each person is a certain number of healthy years of life. So when we suffer ill health and disability, that is regarded as stripping us of those healthy years. DALYs are used to measure the healthy years lost due to ill health.  

The confusion about DALYs enters when people treat DALYs as the healthy years that are lost to ill health. These folks then assume that successful health interventions work by clawing back those lost healthy years (or by "averting their loss" in the first place). Strictly speaking, however, DALYs don't get clawed back when health improves---they disappear or are obliterated. Thus, when one is in poor health, DALYs come into existence and displace one's stock of healthy life years (as set by the normative standard); but when one's health improves, one's newly regained healthy years of life displace or obliterate the DALYs that poor health created. Hence Jamison's dictate: minimize DALYs. One minimizes DALYs either by preventing the poor health that creates them in the first place, or by eliminating and substituting them with regained healthy years of life.

I hope that helps.

 

Patients like aggressive care, but it isn't always good for them

post by Bill Gardner

There is an important study in the Archives of Internal Medicine by Joshua Fenton and his colleagues that reports that 

In a nationally representative sample, higher patient satisfaction was associated with less emergency department use but with greater inpatient use, higher overall health care and prescription drug expenditures, and increased mortality.

The national sample was over 50,000 patients from the Medical Expenditure Panel Survey (MEPS). This is a household survey, meaning that the results are representative of the nation as a whole, rather than being driven primarily by those who received care. Respondents' satisfaction was measured by a composite score based on

4 items pertaining to physician communication, specifically how often in the past 12 months patients' physicians or other health care providers performed the following: (1) listened carefully, (2) explained things in a way that was easy to understand, (3) showed respect for what they had to say, and (4) spent enough time with them... [and] a fifth item in which patients rated their health care from all physicians and other health care providers on a scale of 0 to 10.

To my knowledge, there is universal concensus that these are qualities that we want in our health care. And it has been hoped that by promoting better patient-doctor communication, more patients will get the care they want, avoid care that they do not want, and live healthier lives. 

What the investigators did was to split the survey respondents into four groups based on their overall satisfaction, and then look at their use of health care and survival in the next year. They found that patients who were most satisfied with their medical care in year 1 had 8.8%  greater year 2 total health care expenditures and 9.1% greater prescription drug expenditures compared to those who were least satisfied, after adjusting for demographic characteristics and measures of year 1 health. In addition, "relative to the least satisfied patients at baseline, the most satisfied patients had a 26% greater mortality risk. (emphasis added)"

It is not surprising that those who were more satisfied with care would use more of it. It is completely uncool, however, that this extra care appeared to be killing them, and that -- lambs to the slaughter? -- they nevertheless seemed to believe that they were getting better care.

This study reinforces widespread concerns that patients believe that they need and will benefit from aggressive care, but they would in many cases be better off with less care. And it raises serious questions about whether we should be striving to improve patients' satisfaction with care. The alternative is to focus exclusively on improving health outcomes.

 

Could the US government cut its budget by 10%? Watch Canada

post by Bill Gardner

The Harper government is moving forward on what will be a 5-10% cut in the Canadian federal budget. This may or may not be a good idea, but as an expatriate American, it is amazing to watch it happen.

The graph to the right is the year-to-year % changes in the US budget since 1978. These are the percentage change in absolute dollars relative to the baseline of the previous year. Notice that the budget has decreased in absolute terms in just one year, 2010. On average it grows about 6%, in part because the underlying economy grows. Americans have never experienced anything like the fiscal austerity of the current British government, or that planned by the Canadian Tories. Recall the political struggles in the US in the past summer over the budget. Can you imagine the US doing anything like this?

I'd always understood that parliamentary systems allow countries to make collective decisions that are harder to accomplish in the US, with its separation of powers. I hadn't appreciated how much the difference matters.

Is mandated insurance coverage of contraception an assault on religious liberty?

post by Bill Gardner

The health insurance reform that was part of the Affordable Care Act requires health insurance plans to pay for prescribed contraceptive services. Some, but not all religious institutions are exempted from this requirement. An exemption means that is they offer their employees health insurance, that health insurance does not need to require coverage of prescribed contraception. Under current rules, churches are exempted, but a church-run hospital or hospital is not. There is currently a dispute about whether the exemption should be broadened to include all church-run institutions.

As a matter of health policy, I support the broadest possible access to contraception. Control over reproductive decision making is a fundamental freedom. However, I agree with the editorialist in the Christian Century, that there was a competing public good that would have justified a broader exemption:

we think the common good is also enhanced when religious believers—and religious institutions—are free to act in the public square without sacrificing their religious identity.

The Catholic Bishop of Charleston, however, takes the stronger view that the failure to broaden the exemption is an assault on

the fundamental right to religious liberty  for all citizens of any faith.

This is, I think, an overstatement: I don't think this rises to the level of an assault on a fundamental right and I do not think he is speaking for all US citizens of any faith. Try looking at this from my point of view.

1. I am a Buddhist who has taken a number of religious vows, including not killing. If I were an absolute pacificist, which I am not, I could conscientiously object to military service. But I cannot conscientiously refuse to pay any portion of my taxes, even though I am thereby funding killing in wars that have, in my view, no moral justification. Is this an assault on my religious liberty? 
2. I am absolutely opposed, on religious and ethical grounds, to capital punishments (the graph tracks capital punishments in the US). Nevertheless, they are regularly carried out in my name and paid for with my taxes. Is this an assault on my religious liberty? 
3. I abstain from eating meat, because it kills animals. However, the US government purchases many tons of meat every day for the armed forces, and hence procures the slaughter of thousands of animals. So again, I am paying for this killing. Is this an assault on my fundamental right to religious liberty?
4. Finally, the Catholic Church has historically supported the banning of contraception. Wasn't this religiously-motivated restriction of access an assault on the fundamental right to religious liberty of persons whose religion (or lack thereof) did not bar them from using contraceptives?

The answer to each question is, to some degree, yes: my religious liberty is infringed by points 1-3 and it would have been infringed if there were still restrictions on access to contraception. The government makes me pay for executions. I think that's a more serious  assault on my religious liberty than forcing a Catholic hospital to pay for a diaphragm. Where was the Bishop when I needed him?

The thing is, it turns out that if you are a religious person in a religiously diverse society there will always be some important infringements on your liberties. 

Serious physical abuse of infants and children

From John Leventhal, Kimberly Martin, and Julie Gaither in the new issue of Pediatrics, an estimate of the rate of serious child abuse in the US requiring hospitalization.

Abuse is a terrible problem at any age, but clearly the worst problem is in infancy (There is also a graph for deaths that looks similar.)  Over and above the broken bones, ruptured organs, and the burned skin, serious abuse has a pervasive traummatic effect on neurobiology and psychology of the developing child. And this estimate is the tip of the iceberg of the problem. These are the infants whose injuries led them to be brought to a hospital, and were identified as resulting from abuse. There are many, many others.

I put this forward as a simple plea for support for services in your community for troubled families, and for effective supervision of abusive families.  Do what you can.

 

Will behavior change via mHealth actually work?

post by Bill Gardner

Changing your diet or increasing your daily exercise is hard. You have to do things that you may not care to do -- or you would be doing them already -- and do them in a disciplined, consistent way. Many people have grand hopes that mobile computing devices (mHealth) will help us track our behaviors, making it easier to change. I share those grand hopes.

So I was taken aback by some candid reflections by Marc Hedlund, the former CTO of Wesabe, a web-based software platform that sought to change personal financial behavior. His company competed with Mint.com, and lost. Here is Hedlund's view on why:

Mint focused on making the user do almost no work at all, by automatically editing and categorizing their data, reducing the number of fields in their signup form, and giving them immediate gratification as soon as they possibly could; we completely sucked at all of that. Instead, I prioritized trying to build tools that would eventually help people change their financial behavior for the better, which I believed required people to more closely work with and understand their data. My goals may have been (okay, were) noble, but in the end we didn't help the people I wanted to since the product failed. I was focused on trying to make the usability of editing data as easy and functional as it could be; Mint was focused on making it so you never had to do that at all. Their approach completely kicked our approach's ass... Between the worse data aggregation method and the much higher amount of work Wesabe made you do, it was far easier to have a good experience on Mint, and that good experience came far more quickly. Everything I've mentioned -- not being dependent on a single source provider, preserving users' privacy, helping users actually make positive change in their financial lives -- all of those things are great, rational reasons to pursue what we pursued. But none of them matter if the product is harder to use, since most people simply won't care enough or get enough benefit from long-term features if a shorter-term alternative is available.

Hedlund believes that neither company succeeded in changing personal financial behavior.

Mint totally won at the first (making users happy quickly), and we both totally failed at the second (actually helping people).  No one, in my view, solved the financial problems of consumers.  No one even got close.  Yes, both products helped some people -- ours mostly through a supportive community and theirs mostly through giving people a rough picture of where their money has gone. But when we analyzed the benefits we saw for our users, and when Mint boasted about the benefits they saw for their users, the debt reduction and savings increase numbers directly matched the national averages.  Because our products existed during a deep financial crisis, consumers everywhere cut back, saved more, and tried to reduce their debt. Neither product had any significant impact beyond what the overall economy led people to do anyways.

The lessons of Wesabe are that, first, an mHealth application must make data collection absolutely effortless. However, even when people have access to their personal data, effortlessly, getting them to use it for personal change is an unsolved problem.