{"id":28463,"date":"2012-04-23T16:24:41","date_gmt":"2012-04-23T20:24:41","guid":{"rendered":"http:\/\/blogs.nejm.org\/cardioexchange\/?post_type=voices&p=28463"},"modified":"2012-04-23T16:26:38","modified_gmt":"2012-04-23T20:26:38","slug":"selections-from-richard-lehmans-literature-review-week-of-april-23rd","status":"publish","type":"post","link":"https:\/\/blogs.nejm.org\/cardioexchange\/2012\/04\/23\/selections-from-richard-lehmans-literature-review-week-of-april-23rd\/","title":{"rendered":"Selections from Richard Lehman\u2019s Literature Review: Week of April 23rd"},"content":{"rendered":"

CardioExchange is pleased to reprint selections from Dr. Richard Lehman\u2019s\u00a0weekly journal review blog<\/a>\u00a0at\u00a0BMJ.com<\/a>. Selected summaries are relevant to our audience, but we encourage members to engage with the\u00a0entire blog<\/a>.<\/em><\/p>\n

Week of April 23rd<\/strong><\/p>\n

JAMA\u00a0\u00a0<\/em><\/strong>18 Apr 2012\u00a0 Vol 307<\/strong><\/p>\n

Patient-Centered Outcomes:\u00a0<\/a>George Orwell predicted a nightmare world where soothing words would mean their opposites, and gave his dystopia the date of\u00a01984.\u00a0It was about that year that the term\u00a0patient-centered\u00a0first appeared in\u00a0the medical literature, coinciding with the time when the medical-industrial complex went totally out of control\u00a0in the U.S. and patients were thrown entirely to the mercy of the market. Books and papers about patient-centeredness proliferated in America during the 1990s,\u00a0but the momentum of medicine there\u00a0has\u00a0continued to career in the opposite direction. Now that total chaos and unaffordability loom, the U.S. government has set up the Patient\u00a0Centered\u00a0Outcomes Research Institute\u00a0with a hefty budget to find out how to put things right by finding out what systems of care work best for patients.\u00a0A laudable aim and a fine-sounding name, certain to arouse suspicion among cynics everywhere; but\u00a0this particular cynic\u00a0is\u00a0amazed and optimistic. To find out why, listen to the\u00a0visionary speech<\/a> that Harlan\u00a0Krumholz\u00a0gave to\u00a0the PCORI\u00a0Patient and Stakeholder\u00a0group a few weeks ago.\u00a0This\u00a0goes way beyond the usual rhetoric of\u00a0being nice and involving patients,\u00a0and commits PCORI to a radical agenda of patient empowerment \u2013 the only way that health systems the world over can reclaim the true purpose of medicine. This article shows\u00a0how\u00a0Harlan\u2019s vision is shared by others in the developing organization.<\/p>\n

Uncertainty:<\/a>\u00a0But the moment that you attempt to empower patients, you run into problems. Patients as well as doctors like to believe that there must be a\u00a0single right answer\u00a0for every problem, when very often there is not. As I\u2019ve said before, Harlan\u2019s surname (meaning crooked wood in German) always reminds me of Kant\u2019s famous dictum, \u201cout of the crooked timber of humanity, no straight thing was ever made.\u201d And it\u2019s no good torturing the evidence by exercises in subgroup analysis and\u00a0modeling: in most of medicine, there is irreducible uncertainty.\u00a0Here\u00a0is a nice short philosophical piece by David Kent and\u00a0Nilay\u00a0Shah, headed with the splendid observation of George Box that all\u00a0models are wrong, but some are useful.<\/p>\n

Involving Patients in Research:<\/a>\u00a0Three\u00a0non-clinicians discuss the problems of\u00a0continuous patient engagement in comparative effectiveness research. Now comparative effectiveness research is actually fiendishly difficult, for reasons I will try to outline very briefly in a moment; and securing patient involvement in research is also difficult, but absolutely essential. In fact it will be a measure of PCORI\u2019s success if it can demonstrate that every aspect of its research is genuinely patient-centered \u2013 i.e., that it listens to the patient voice at every stage, and that every output has direct bearing on decision making with patients and society.\u00a0The ultimate measure of its success, ironically, will be the disappearance of the concept of the patient altogether.<\/p>\n

Medicine-Based Evidence:\u00a0<\/strong>In this\u00a0hefty themed issue of\u00a0JAMA<\/em>, there now follow five examples of\u00a0comparative effectiveness research\u00a0(CER),\u00a0followed by a knotty editorial with the title “Is It Time for Medicine-Based Evidence?”<\/a> And here is the problem for you and for me, dear Reader: you cannot properly assess a paper on outcomes research or\u00a0CER without some understanding of the following methods\u00a0\u2013\u00a0multiple linear regression or analysis of covariance for continuous (dimensional) outcomes, logistic regression for binary (dichotomous) variable outcomes, proportional hazards analysis or Cox regression when a time interval is relevant to a binary outcome (i.e., survival analysis), and Poisson regression when outcomes are measured as counts. Moving on, you then need to employ these techniques in\u00a0one or both of\u00a0two conceptual processes which can help to balance the characteristics of unmatched groups in observational studies:\u00a0propensity scores\u00a0and\u00a0instrumental variables. There are plenty of statistics texts to confuse the unwary, but there is no simple, comprehensible guide to outcomes research for the non-specialist. I know, because I am trying to help write one. And I am hoping somebody else will deal with all this while I write about patient-centeredness.\u00a0So finally, back to this study<\/a>.\u00a0You need not read it: it is simply a good teaching example for those who want to understand the use of propensity scoring in retrospective cohort studies. The study concludes that without needing a randomized controlled trial, we can be pretty certain that adding\u00a0bevacizumab\u00a0to\u00a0carboplatin-paclitaxel\u00a0chemo for\u00a0advanced non\u2013small cell lung cancer\u00a0makes no difference. And that is useful knowledge for decision-making.<\/p>\n

\u00a0NEJM \u00a0<\/em>19\u00a0Apr 2012 \u00a0Vol\u00a0366<\/strong><\/p>\n

CABG vs. PCI:<\/a>\u00a0Now that we\u2019ve\u00a0finally escaped from\u00a0JAMA\u00a0<\/em>and all this stuff about CER methodology, let\u2019s look at this first paper in the New England Journal of Medicine.<\/em> Being in NEJM<\/em>,\u00a0funded by the\u00a0NHLBI, and conducted by a distinguished team of researchers, it must be right, and it concludes that: \u201cIn this observational study, we found that, among older patients with\u00a0multivessel\u00a0coronary disease that did not require emergency treatment, there was a\u00a0long-term survival advantage among patients who underwent CABG as compared with patients who underwent PCI.\u201d Proof at last of what we all suspected: new tubes must be better than stents.\u00a0But hang on, what was the absolute mortality difference between these groups? The median follow-up period was 2.67 years, at which time the survival lines were beginning to diverge in favor of CABG, but not by very much. In the minority of patients followed to 4 years, the difference was statistically significant and stood at an absolute value of 4.4% provided one accepts the methods of the study. And what are these methods? Why, our new friends\u00a0propensity scores and inverse-probability-weighting adjustment.\u00a0So we are back to the problems of comparative effectiveness research with a vengeance.\u00a0The left brain, without the help of complex statistical computation, cannot interrogate these results; while my creaky old right brain tells me that I cannot make use of this information in decision-making with patients, because there are too many variables to rely on such small differences. In fact I think we may need new methods of describing the confidence limits when using\u00a0these two-stage\u00a0weighting adjustments\u00a0with unbalanced groups. So do we need another RCT comparing CABG with PCI using current methods? The editorial discusses this question, but not with any satisfactory conclusion.\u00a0I think equipoise still best describes the clinical situation.<\/p>\n

On- Vs. Off-Pump CABG:<\/a>\u00a0And now, like a Common White Butterfly, we must return to the field of cabbage.\u00a0CABG\u00a0can, as all of you know, be performed with a\u00a0cardiopulmonary bypass pump\u00a0or without. Off-pump CABG is technically more challenging but is supposed to reduce the amount of debris reaching the brain during surgery. This trial (given the unoriginal acronym CORONARY \u2013 how much jollier BRASSICA might have been) randomized 4752 patients in 79 centers to have their cabbage done one way or the other.\u00a0At 30 days, there was no significant difference in gross outcomes, but they acknowledge that\u00a0\u201cNeurocognitive outcomes and economic data may have an important effect on and substantially influence the ultimate interpretation of the primary findings.”<\/p>\n","protected":false},"excerpt":{"rendered":"

This week, Richard discusses JAMA’s coverage of patient-centered care and all things CABG in NEJM.<\/p>\n","protected":false},"author":475,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[231,1230,233,1231],"class_list":["post-28463","post","type-post","status-publish","format-standard","hentry","category-general","tag-cabg","tag-cabg-vs-pci","tag-outcomes","tag-patient-centered-care"],"_links":{"self":[{"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/posts\/28463","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/users\/475"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/comments?post=28463"}],"version-history":[{"count":0,"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/posts\/28463\/revisions"}],"wp:attachment":[{"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/media?parent=28463"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/categories?post=28463"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/tags?post=28463"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}