Thursday, February 28, 2013


VBID in Medicare: Will CMS Look Before It Leaps?
In recent testimony before the U.S. House Ways and Means Subcommittee on Health, A. Mark Fendrick, Director of the Center for Value-Based Insurance Design (VBID) at the University of Michigan, advocated for what he described as “the essential role of clinical nuance” in Medicare, specifically “reducing financial barriers to evidence-based services and high-performing providers” while “imposing disincentives to discourage use of low-value care."[1] Fendrick’s proposal included two major components as “an interim step” to be applied initially only within Medicare Advantage Plans (MAPs): first, allowing MAPs to use higher copayments to deter use of “low-performing” providers, rather than simply excluding those providers from their networks as MAPs are currently permitted to do; and second, allowing MAPs to vary copayments for medical services or drugs based on their clinical value. The latter idea is relatively old, as current health policy proposals go—it was first described in 2001 as a “benefit-based copay for prescription drugs,” in which medication copayments were to be based on clinical value rather than drug cost. The theory is that if higher-value treatments (e.g., beta blockers following a heart attack) are available for a lower copayment, patients will be more likely to use them.

Fendrick set forth his proposal for what he described as “the common-sense step of allowing co-payments to vary based on whether an intervention is high-value or low-value” as part of a broader vision for the U.S. health care system as a whole. If we were to “[reallocate] health care dollars to services for which there is clear evidence for improving clinical outcomes,” Fendrick argued, “we could simultaneously enhance quality and reduce the amount we spend.” Quite a promise—but assuming that this assessment is accurate, will lowering copayments for “high-value” services and increasing copayments for “low-value” services help us get there?
In an evidence-based health care system, the answer should depend on the findings of high-quality research on the degree to which copayment changes actually influence the behavior of insured beneficiaries. I’ll discuss this research—and what it teaches us about how to evaluate and use study findings in making policy decisions—in more detail in coming posts. But for now, consider that the “growing body of evidence” for VBID mentioned in Fendrick’s testimony includes primarily observational (nonexperimental) studies, which earn generally low quality ratings in evidence-grading systems.[3] Stronger, experimental evidence about VBID is limited to a single randomized controlled trial (RCT) conducted in a commercially insured, non-Medicare population of heart attack survivors.[4] Some good-quality observational data on cost-sharing in Medicare samples are available.[5] However, the refutation of even the highest-quality observational findings by stronger RCT evidence has become so commonplace as to be the rule rather than the exception in health care—as is well known to those familiar with ACCORD, ADVANCE, and the WHI, to cite just a few examples.[6]

So, in considering VBID at the present time, the Centers for Medicare & Medicaid Services (CMS) is faced with limited evidence coupled with enthusiastic advocacy. It may seem like an unusual combination, but CMS has been here before, about a decade ago. At that time, advocates of providing population disease management (PDM) programs to Medicare beneficiaries with chronic diseases pointed to numerous, mostly observational, studies documenting positive health outcomes and return-on-investment (ROI) estimates of up to $11-$14 in medical cost reductions.[7] The PDM proposal made good common sense because it was widely recognized that beneficiaries with chronic disease were “a large and costly subgroup of the Medicare population” that struggled to “navigate a system … structured and financed to manage acute, rather than long-term, health problems.”[7] PDM, which provides user-friendly health education and a readily available source of advice outside of physician office hours, seemed ideally suited to address the problem. According to Senate testimony provided in 2002 by Dan Crippen, then Director of the Congressional Budget Office, “the long-range fiscal challenges facing the Medicare program” made the prospect of adding a PDM benefit to Medicare “tantalizing” because “proponents claim that such a benefit would improve the quality of care that beneficiaries receive and at the same time reduce federal costs.”[8]
Sound familiar?

But rather than adopt the widely touted PDM benefit without rigorously testing it first, CMS initiated the Medicare Health Support (MHS) experiment in 2005 to randomize about 240,000 beneficiaries with diabetes and/or congestive heart failure to receive PDM provided by nurse-based call centers or usual care. The MHS results were both disappointing and inconsistent with the weaker research evidence that had been enthusiastically highlighted by PDM benefit supporters. Far from producing an enormous ROI because of better medical outcomes, PDM had no significant effect on hospitalizations, emergency room use, or total health care cost.[9]
What can we take away from the MHS example? As Casazza et al. observed in a recent report on “myths, presumptions, and facts about obesity,” it has long been recognized in medical science that circumstances sometimes necessitate policy adoption absent experimental evidence—specifically, when conducting an RCT would be infeasible, unethical, or unnecessary because “observed associations are not plausibly due to confounding.”[10] However, Casazza et al. pointed out that this recognition has sometimes been used as an excuse for accepting weak evidence “by those who are eager to garner support for a proposal in the absence of strong data from randomized studies.” In other words, when RCTs are feasible and there is a reasonable possibility that observational evidence has been contaminated by confounding effects (usually baseline differences among study groups that cannot be statistically controlled in analysis), methodologically weaker evidence should be viewed as unacceptable for the purposes of public policy making. The MHS experiment reflected this view.

Such should be the case with consideration of VBID in Medicare. An RCT is feasible, there is a possibility that observational evidence will be overturned by stronger experimental data, and the stakes are high. Consider that, at about the time that the decision to conduct the MHS trial was made, the most recent data available showed prevalence rates of 14% and 18% for CHF and diabetes, respectively, in the Medicare fee-for-service beneficiary population.[7] With monthly administrative fees of $74 to $159 paid to PDM vendors in the MHS[9], 85% participation[9], and a 2005 enrollee count of about 43.4 million[11], a “back-of-the-envelope” calculation assuming an overall prevalence of about 25% for both diseases (combined) suggests that CMS would have spent an additional $8-$18 billion annually had a PDM benefit been adopted as suggested by advocates—with no discernible health improvement for Medicare beneficiaries. For this reason, the decision to conduct the MHS provides us with a good example of evidence-based policy making in action and, perhaps even more importantly, of why health care research methods matter.

[1] Fendrick AM. The essential role of clinical nuance in Medicare’s benefit design. Testimony before U.S. House of Representatives Ways and Means Subcommittee on Health. February 26, 2013.
[2] Fendrick AM, Smith DG, Chernew ME, Shah SN. A benefit-based copay for prescription drugs: patient contribution based on total benefits, not drug acquisition cost. Am J Manag Care. 2001;7(9):861-67.
[3] McAlister FA, van Diepen S, Padwal RS, Johnson JA, Majumdar SR. How evidence-based are the recommendations in evidence-based guidelines? PLoS Med. 2007;4(8):1325-32; and Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) Working Group. Grading quality of evidence and strength of recommendations. BMJ. 2004;328:1490-94.
[4] Choudhry NK, Avorn J, Glynn RJ, et al. Full coverage for preventive medications after myocardial infarction. N Engl J Med. 2011;365:2088-97.
[5] For example: Tseng CW, Brook RH, Keller E, Steers WN, Mangione CM. Cost-lowering strategies used by Medicare beneficiaries who exceed drug benefit caps and have a gap in drug coverage. JAMA. 2004;292(8):952-60; Raebel MA, Delate T, Ellis JL, Bayliss EA. Effects of reaching the drug benefit threshold on medicare members’ healthcare utilization during the first year of Medicare part D. Med Care. 2008;46(10):1116-22; Trivedi AN, Moloo H, More V. Increased ambulatory care copayments and hospitalizations among the elderly. N Engl J Med. 2010;362:320-28.
[6] Rossouw JE, Anderson GL, Prentice RL, et al.; Writing Group for the Women’s Health Initiative Investigators. Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results from the Women’s Health Initiative randomized controlled trial. JAMA. 2002;288(3):321-33; ADVANCE Collaborative Group, Patel A, MacMahon S, Chalmers J, et al. Intensive blood glucose control and vascular outcomes in patients with type 2 diabetes. N Engl J Med. 2008;358(24):2560-72; Action to Control Cardiovascular Risk in Diabetes Study Group, Gerstein HC, Miller ME, Byington RP, et al. Effects of intensive glucose lowering in type 2 diabetes. N Engl J Med. 2008;358(24):2545-59.
[7] Cromwell J, McCall N, Burton J. Evaluation of Medicare Health Support chronic disease pilot program. Health Care Finance Rev. 2008;30(1):47-60; Foote S. Population-based disease management under fee-for-service Medicare. Health Aff (Millwood). 2003 Jul-Dec;Suppl Web Exclusives:W3-342-56.
[8] Crippen DL. Disease management in Medicare: data analysis and benefit design issues. CBO Testimony before Special Committee on Aging, United States Senate. September 19, 2002.
[9] McCall N, Cromwell J. Results of the Medicare Health Support disease-management pilot program. N Engl J Med. 2011;365(18):1704-12.
[10] Casazza K, Fontaine KR, Astrup A, et al. Myths, presumptions, and facts about obesity. N Engl J Med. 2013;368:446-54.
[11] Henry J. Kaiser Family Foundation. State Health Facts. Total number of Medicare beneficiaries, 2005.

Monday, February 25, 2013


Confusing Association with Causation:
What 10,675 Residents of London in 1853 and
23 Million U.S. Adults with Type 2 Diabetes May Have in Common

A tidbit of health news[1] that garnered considerable media attention recently highlights a pattern of events that occurs all too often when health care research is presented in the popular press. First comes a peer-reviewed, scientific report in which the investigators describe—in an appropriately measured, accurate way—an association between a risk factor and an outcome, sometimes hinting, while not openly declaring, a causal relationship. (Often, this initial cautious interpretation is used because journal peer reviewers and editors insist on it.) Second, the principal investigator’s sponsoring institution issues a press release that more directly refers to a possibility that the risk factor caused the outcome and calls for public action. Third, the media kicks the whole thing up a notch by overtly asserting the existence of an important public health risk that should be addressed by patients, physicians, or the government. Rounding out the “informational” picture, interested blogs pick up the news, often removing even the slightest hint of the investigator’s original (appropriate) caution in interpreting the study findings. The results for public health are misinformation, confusion, and sometimes decision making that does more harm than good.
Among the latest examples is a study of the association between the use of insulin and at least one negative health outcome (major cardiac event, cancer, or death) in patients treated for type 2 diabetes in the United Kingdom from 2000-2010, conducted by Craig Currie and colleagues.[2] Patients were not randomized (assigned by the investigators) to treatment, as in an experiment. Instead, the study was observational, meaning that the investigators measured (observed) the outcomes of patients whose doctors chose treatments—including insulin and/or oral drugs, such as metformin or sulfonylureas. Patients were classified into cohorts (groups) based on the treatment they received at any given time. For example, a patient initially taking metformin (the most commonly recommended first-line treatment) who was then switched to insulin because the metformin didn’t control his/her blood sugar was classified into two cohorts: the metformin cohort while the disease was being controlled by metformin, then the insulin cohort after the disease progressed to the point that insulin was necessary. Thus, by design, the insulin cohort would be expected to be “sicker” (have less well controlled disease and more negative outcomes) than the metformin cohort.

As my explanation above hints, the problem with observational designs of this type is that doctors choose treatments based on patient characteristics, usually including disease severity, comorbidities (other serious medical conditions), and age. So, there is often no way to tell whether the patients’ outcomes are due to the treatment or to the patient characteristics, a problem technically known as “confounding by indication.” Appropriately, Currie et al. acknowledged this possibility in discussing their findings:
Because diabetes is a progressive disease, therapy choice will reflect this progression such that patients who are well controlled on first-line therapy, usually metformin, will remain on this therapy, whereas those who fail in the sense of increased levels of glycemia or development of complications will be treated more aggressively with the addition of other treatment options.”[2]

The study abstract also appropriately noted that “differences in baseline characteristics between treatment groups should be considered when interpreting these results.”[2]
But, a press release from Currie’s sponsoring institution was a little less cautious, with a headline that declared: “Taking insulin to control type 2 diabetes could expose patients to ‘greater risk of health complications’.”[3] Although noting for the press release that “patients currently being treated with insulin should not, under any circumstances, stop taking their medications,” Currie added that “this study shows that we need to investigate this matter urgently and the drug regulatory authorities should take interest in this issue.”

Predictably, media headlines went a little further than the press release in describing the hazards of insulin treatment, pronouncing insulin “risky for type 2 diabetics.”[1] And blog postings proclaimed the “risk” even more boldly. One blogger stated that “insulin doubles death rate in type 2 diabetics,” that insulin monotherapy (treatment with insulin alone) “resulted in” a wide variety of negative health outcomes, including heart attacks and kidney complications, and that “the general public [has become] a mass of guinea pigs for medical experimentation.”[4]
The effects of all this misinterpretation on public health, especially the decisions made by the approximately 23-24 million U.S. adults with type 2 diabetes,[5] may not be known for some time. But, for a sense of the potential damage, we can look to 19th century London, where residents were understandably terrified of cholera—a virulent disease of the intestinal tract that killed 50,000 British residents in a two-year period beginning in 1848,[6] and 10,675 Londoners in 1853 alone.[7] At the time, prevailing wisdom, shared by the vast majority of physicians and, unfortunately, politicians, was that cholera was caused by miasma (bad air). “Science” contributed to the erroneous view with an analysis of the association between elevation above the Thames River and cholera deaths—the higher above the Thames, where the air smelled better, the lower the mortality rate.[6] The association was so strong that one could predict cholera mortality rates based on elevation with nearly perfect accuracy.[8]

The only problem with this theory was, of course, that the nearly perfect association was entirely coincidental and had nothing whatsoever to do with the actual cause of cholera. At higher elevations above the Thames, residents were less likely to be exposed to water contaminated with Vibrio cholerae, the true causal agent of the disease. Unfortunately, as Steven Johnson notes in his fascinating book, The Ghost Map, zealous politicians were erroneously convinced by association that “all smell is disease,” and legislated a public works system to abolish (smelly) cesspools by dumping sewage into the Thames River. As a result, Johnson notes: “In the space of about thirty-five years, the Thames had been transformed from a fishing ground teeming with salmon to one of the most polluted waterways in the world—all in the name of public health,” thus “[delivering] the cholera bacteria directly to the mouths of Londoners.”[6]
In coming posts, I’ll be providing more examples of the potential harm caused by the “association versus causation” phenomenon because it is both frequent and much more important than is often acknowledged in research reporting. I’ll also be examining the old, ubiquitous enemy of public policy driven by the best of intentions—the unintended consequence. But meanwhile, perhaps the most important moral of the cholera and diabetes stories is that we shouldn’t be getting our health news from either blogs or politicians. We need to be able to use research sources, as much as possible, to read and interpret information on our own. It’s my hope that this blog will move us farther on that path. What do you think? Write to me or leave a comment below.

Sources:
[1] Tate N. Insulin risky for type 2 diabetics: study. NewsmaxHealth. February 6, 2013; and BBC News. Type 2 diabetes: insulin greater risk, finds Cardiff study. February 4, 2013.
[2] Currie CJ, Poole CD, Evans M, Peters JR, Morgan CL. Mortality and other important diabetes-related outcomes with insulin vs other antihyperglycemic therapies in type 2 diabetes. J Clin Endocrinol Metab. 2013;98(2):668-677.
[3] Cardiff University News Centre. Taking insulin to control type 2 diabetes could expose patients to ‘greater risk of health complications’. February 4, 2013.
[4] Stevenson H. Insulin doubles death rate in type 2 diabetics: study. GreenMedInfo.com. February 19, 2013.
[5] Of about 25.6 million U.S. adults with diagnosed or undiagnosed diabetes in 2011, approximately 90%-95% had type 2 diabetes. http://www.cdc.gov/diabetes/pubs/pdf/ndfs_2011.pdf
[6] Johnson S. The Ghost Map. New York: Riverhead Books; 2006.
[7] UCLA Department of Epidemiology, School of Public Health. Broad street pump outbreak.
[8] See: UCLA Department of Epidemiology, School of Public Health. Cholera mortality—London, 1849.
If you read or heard any news today, chances are good that you came across at least one story about research in medicine, pharmacy, public health, or health care policy. You might have learned that the findings point to a groundbreaking medical development, that insurers or public health systems will not cover a particular treatment because of its cost, that one or more investigators behaved unethically, that a particular demographic group will be affected by the results—the list of potential clinical, economic, and even political implications is nearly endless.

And this barrage of information is not going to stop anytime soon. The Affordable Care Act, or PPACA, is introducing a host of innovations to the health care delivery system, many of which are being evaluated for the first time in studies that are being posted in news sources almost daily. Will this research show that PPACA provisions achieved their intended objectives—or that they introduced unintended consequences?

At the heart of all these issues lies an often overlooked question: were the study methods used to assess health care policies and treatments valid and reliable? Even for non-researchers, this question is critically important, because the quality of the medical services that you receive depends on the quality of the evidence used to assess them.

In this blog, we will explore the relationship between health care research methods and the policies and treatments that affect our lives—as citizens, as patients, and sometimes as caregivers to family members with medical needs. But for those of you who either never took or don’t remember your methods and statistics classes in college—and for those who took them but don’t want to remember them—fear not. We’ll keep the content both informative and easy to read, even for non-researchers.

About Kathleen Fairman

Kathleen Fairman, author of Health Care Research Done Right, is a research investigator and author with 25 years of experience in evaluating public and private-sector health care programs. With a passion for encouraging the pursuit of excellence in research, she shares vital insights about why research methods—those seemingly mundane study details that are sometimes overlooked—matter deeply to the welfare of patients served by the health care system. Readers will benefit greatly from her wisdom, grace, and humor—and find that good research methodology can be both practical and fun.