Another guideline problem – inaccurate CV risk estimation

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Category : Medical Rants

When the recent lipid primary prevention guideline released in 2013, I was deemed at “high risk” for CV disease.  This article – Recent Update to the US Cholesterol Treatment Guidelines summarizes the guideline.  The guideline uses a risk calculator to guide lipid lowering (mostly statin) prescribing.

Many critics (including me) felt that the calculator greatly overestimated CV risk.  Since the guideline depends on accurate estimation of that risk, testing and potentially improving the calculator has a high priority.

A recent Annals of Internal Medicine article – Clinical Implications of Revised Pooled Cohort Equations for Estimating Atherosclerotic Cardiovascular Disease Risk – tests the original calculator against current cohort data, and then describes 2 new calculators.  The article, very statistically technical, shows a marked improvement in these estimates.

Is this a big deal?  Let’s use my data as an example.  I am 69 years old, have a BP of 124/78, total cholesterol 187 and HDL 75.  I have never smoked, and do not have diabetes mellitus.  Using the guideline endorsed calculator, my 10 year CV risk is 12.9%.  The calculator has this suggestion:

On the basis of your age and calculated risk for heart disease or stroke over 7.5%, the ACC/AHA guidelines suggest you should be on a moderate to high intensity statin.

The newer, better validated and calibrated, calculator estimates my risk at 7.2%.  This is a huge difference!  With this calculator I do not meet the very aggressive guideline that would suggest that I take a statin.

From the Annals article: “Approximately 11.8 million U.S. adults previously labeled high-risk (10-year risk ?7.5%) by the 2013 PCEs would be relabeled lower-risk by the updated equations.”

This is not a minor issue! How many side effects would we develop in 11.8 million adults?  How much money would we spend on medications?  We know that labeling patients leads to increased work absenteeism.  What other negative outcomes might come or have already come from an inaccurate estimator?

Now a critic might ask why I am so in favor of the newer calculator.  Reading the article, and understanding the problems of risk calculators, their data convinces me.

I hope the AHA/ACC read this article and modify their recommendations.  I will certainly not start taking a statin given the more accurate estimation.

Sore throats – #thefineprint

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Category : Medical Rants

Saying that sore throats are simple has become a trope, as thus many physicians do not seem to have a thoughtful approach to adolescent/young adult pharyngitis.  As the author of the Centor Score, I would like you to consider these points when seeing sore throat patients.

  1. The most important use of the score involves identifying those who need neither diagnostic tests nor antibiotics.  Too many urgent cares run a group A rapid strep test on everyone with a sore throat.
  2. The score is meant for acute (3 day or less) sore throat symptoms.
  3. The score stratifies adolescent/young adults with bacterial pharyngitis – group A strep, group C/G strep and fusobacterium necrophorum
  4. Sore throat improve over 3-5 days, if a sore throat is worsening, the patient deserves further consideration.  This case report we published could help – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1824744/
  5. Pre-adolescents have differing severity and rarely have infections with bacteria other than GAS.

Most sore throats are simple.  Our job is to recognize when the patient does not fit the usual illness script

The danger of pronouncements in medicine

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Category : Medical Rants

“Experts” mean to improve health.  They have great intentions, but we all know what is paved with good intentions.

This week I twice checked my blood pressure on a machine at our grocery store.  The first time my blood pressure with 134/82 and the machine told me I had an elevated blood pressure.  The second time it was 124/78 and it told me that my blood pressure was elevated. I was very pleased with my blood pressure, and astonished.  The machine justifies these interpretations because a group of “experts” wrote and published a guideline pronouncement that redefined almost everyone as either being hypertensive or at least elevated.

That same group championed a flawed risk calculator that greatly overestimates my risk of coronary artery disease.  As soon as they release risk calculator (now touted for both statin use and hypertension treatment) Dr. Nissen wrote this opinion piece – Risk Calculator for Cholesterol Appears Flawed

The latest Annals of Internal Medicine includes a very complex, careful alternative to that risk calculator – Clinical Implications of Revised Pooled Cohort Equations for Estimating Atherosclerotic Cardiovascular Disease Risk

Results:
The 2013 PCEs overestimated 10-year risk for atherosclerotic CVD by an average of 20% across risk groups. Misestimation of risk was particularly prominent among black adults, of whom 3.9 million (33% of eligible black persons) had extreme risk estimates (<70% or >250% those of white adults with otherwise-identical risk factor values). Updating these equations improved accuracy among all race and sex subgroups. Approximately 11.8 million U.S. adults previously labeled high-risk (10-year risk ?7.5%) by the 2013 PCEs would be relabeled lower-risk by the updated equations.

The authors are incredibly polite in their discussion. I refuse to play the politeness game.

This example is only one in a series of many such over reaching pronouncements.

Why does this happen?  We work in a world that champions evidence based decision making.  We believe that evidence exists without bias.  But cognitive psychologists have taught us (just as they have taught economists) that data require interpretation.  As Dr. Verghese recently said, “Medicine is messy and complicated, because humans are messy and complicated.”  Yet our experts try to impose simple rules for patient care.

Confirmation bias leads many groups to focus on possible benefits and minimize likely risks.  Labeling someone incorrectly as having hypertension or needing a statin is a major mistake.  But yet the experts champion a flawed calculator and flawed targets.  Obviously these pronouncements really aggravate me.  And I do not believe that I am unique among rational physicians.

Please decrease these pronouncements.  Save your guidelines and recommendations to situations that are very clear.  Embrace the controversies and allow physicians to consider multiple patient considerations when making decisions with their patients.

If you are skeptical of my rant, just consider how many dueling guidelines we have.  Guidelines have assumed almost religious fervor in some quarters, yet when panels disagree on the recommendations we are placed in an impossible situation.

Save the money and time spent on crafting these missives and explain why our decision making is appropriately messy.  Embrace the messiness.  We all know that the emperor has no clothes.  Do not pretend otherwise.

New drugs for hyperkalemia

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Category : Medical Rants

FDA Approves Lokelma for Hyperkalemia

The US Food and Drug Administration (FDA) has approved sodium zirconium cyclosilicate (Lokelma, AstraZeneca) — a medication that rapidly restores normal potassium levels — for adults with hyperkalemia.

Formerly known as ZS-9, the drug is a “highly-selective, oral potassium-removing agent,” the company explains in a company news release.

Hyperkalemia has become a significant problem.  With more type 2 Diabetes Mellitus, we are seeing an explosion of chronic kidney disease.  In patients with CKD 3b and 4, patients often develop hyporenin, hypoaldosterone and thus type IV RTA.  However, many patients have relative hyporenin and therefore decreased angiotensin 1.  When these patients take an ACE inhibitor or and ARB, they develop hyperkalemia because of inadequate aldosterone.

And these patients have an absolute indication for an ACE-I or ARB.  Thus, we have a conundrum.  How do we successfully treat their systolic dysfunction or progressive CKD.

Drug companies see an niche.  Sodium polysterene (Kayexalate) is not adequate due to dangerous side effects.  Patiromer (Valtessa) was released first, now this new option.

What will be their roles?  What will be the pricing?

This is all interesting, and we will follow the indications for its use with interest.

Syncope week – Day 2 – high-risk features

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Category : Medical Rants

Our first task is to decide whether the patient needs admission. The list is not exhaustive, but very suggestive.  These features require admission and careful cardiac evaluation:

Major

  1. New onset chest pain, headache, abdominal pain or breathlessness
  2. Syncope during exertion or when supine!
  3. Sudden palpitation followed by syncope

Minor

  1. No warning symptoms or short (<10 sec) prodrome
  2. Family history of sudden cardiac death at young age
  3. Syncope in sitting position

Past Medical History

  1. Known heart disease – decreased LVEF, or known coronary artery disease

Physical Exam

  1. Unexplained BP < 90 in emergency department
  2. GI bleed (heme positive stools)
  3. Persistent bradycardia while awake in absence of physical training
  4. Unexplained systolic murmur

Electrocardiogram

  1. Acute ischemia
  2. Mobitz II or III AV block
  3. Slow atrial fibrillation
  4. Bundle branch blocks, intraventricular conduction delays, Q waves
  5. Ventricular tachycardia – sustained or non-sustained
  6. Dysfunction of pacemaker or AICD
  7. Type I Brugada
  8. Prolonged QT

Syncope guidelines published Day 1

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Category : Medical Rants

The Europeans have published a thorough guideline for syncope.  I have not had time to absorb the entire guideline – it is dense but seems very well done.  There is enough material here for 5 days of short posts rather than one long post. Today, I have copied their key messages.

2018 ESC Guidelines for the diagnosis and management of syncope, European Heart Journal

10. Key messages

The ESC Task Force has selected 19 simple rules to guide the diagnosis and management of syncope patients with TLOC (total loss of consciousness) according to the 2018 ESC Guidelines on syncope:

Diagnosis: initial evaluation

At the initial evaluation answer the following four key questions:

• Was the event TLOC?

•?In cases of TLOC, are they of syncopal or non-syncopal origin?

•?In cases of suspected syncope, is there a clear aetiological diagnosis?

•?Is there evidence to suggest a high risk of cardiovascular events or death?

At the evaluation of TLOC in the ED, answer the following three key questions:

•?Is there a serious underlying cause that can be identified?

•?If the cause is uncertain, what is the risk of a serious outcome?

•?Should the patient be admitted to hospital?

In all patients, perform a complete history taking, physical examination (including standing BP measurement), and standard ECG.

Perform immediate ECG monitoring (in bed or telemetry) in high-risk patients when there is a suspicion of arrhythmic syncope.

Perform an echocardiogram when there is previous known heart disease, or data suggestive of structural heart disease or syncope secondary to cardiovascular cause.

Perform CSM (carotid sinus massage) in patients >40 years of age with syncope of unknown origin compatible with a reflex mechanism.

Perform tilt testing in cases where there is suspicion of syncope due to reflex or an orthostatic cause.

Perform blood tests when clinically indicated, e.g. haematocrit and cell blood count when haemorrhage is suspected, oxygen saturation and blood gas analysis when hypoxic syndromes are suspected, troponin when cardiac ischaemia-related syncope is suspected, and D-dimer when pulmonary embolism is suspected, etc.

Diagnosis: subsequent investigations

9. Perform prolonged ECG monitoring (external or implantable) in patients with recurrent severe unexplained syncope who have all of the following three features:

??•?Clinical or ECG features suggesting arrhythmic syncope.

??•?A high probability of recurrence of syncope in a reasonable time.

??•?Who may benefit from a specific therapy if a cause for syncope is found.

10. Perform EPS in patients with unexplained syncope and bifascicular BBB (impending high-degree AV block) or suspected tachycardia.

11. Perform an exercise stress test in patients who experience syncope during or shortly after exertion.

12. Consider basic autonomic function tests (Valsalva manoeuvre and deep-breathing test) and ABPM for the assessment of autonomic function in patients with suspected neurogenic OH.

13. Consider video recording (at home or in hospital) of TLOC suspected to be of non-syncopal nature.

Treatment

14. To all patients with reflex syncope and OH, explain the diagnosis, reassure, explain the risk of recurrence, and give advice on how to avoid triggers and situations. These measures are the cornerstone of treatment and have a high impact in reducing the recurrence of syncope.

15. In patients with severe forms of reflex syncope, select one or more of the following additional specific treatments according to the clinical features:

•?Midodrine or fludrocortisone in young patients with low BP phenotype.

•?Counter-pressure manoeuvres (including tilt training if needed) in young patients with prodromes.

•?ILR-guided management strategy in selected patients without or with short prodromes.

•?Discontinuation/reduction of hypotensive therapy targeting a systolic BP of 140 mmHg in old hypertensive patients.

•?Pacemaker implantation in old patients with dominant cardioinhibitory forms.

16. In patients with OH, select one or more of the following additional specific treatments according to clinical severity:

•?Education regarding lifestyle manoeuvres.

•?Adequate hydration and salt intake.

•?Discontinuation/reduction of hypotensive therapy.

•?Counter-pressure manoeuvres.

•?Abdominal binders and/or support stockings.

•?Head-up tilt sleeping.

•?Midodrine or fludrocortisone.

17. Ensure that all patients with cardiac syncope receive the specific therapy of the culprit arrhythmia and/or of the underlying disease.

18. Balance the benefits and harm of ICD implantation in patients with unexplained syncope at high risk of SCD (e.g. those affected by left ventricle systolic dysfunction, HCM, ARVC, or inheritable arrhythmogenic disorders). In this situation, unexplained syncope is defined as syncope that does not meet any class I diagnostic criterion defined in the tables of recommendations of the 2018 ESC Guidelines on syncope and is considered a suspected arrhythmic syncope.

19. Re-evaluate the diagnostic process and consider alternative therapies if the above rules fail or are not applicable to an individual patient. Bear in mind that Guidelines are only advisory. Even though they are based on the best available scientific evidence, treatment should be tailored to an individual patient’s need.

The value of controversy in medicine – sepsis

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Category : Medical Rants

Everywhere I look in medicine today I see controversy.  We see competing guidelines.   We see subspecialty organizations write indignant screeds about another organizations guidelines.

One of the most popular Grand Rounds styles involves debates.  The audience generally rates debates very highly.

As physicians we approach medicine cerebrally.  Controversy should make us think.  We actually like thinking.

Perhaps the largest current controversy involves the sepsis bundle.  While this controversy is attracting much heat, we have many other important controversies.

Why do these controversies develop?  With apologies to true believers, we must return to my favorite Nietzsche quote,  “There are no facts, only interpretations.”

We in medicine value evidence.  We assume that we can resolve controversy with data.  But almost all interventions carry harms and benefits.  How much harm should we tolerate to achieve how much benefit?  Until we understand that problem, we cannot really understand the reason for controversy.  Confirmation bias also complicates this problem.  In confirmation bias (to which we all fall prey), we highly value any evidence that supports our beliefs and discount evidence that would argue against our beliefs.

In the sepsis guideline and bundle controversy, some experts want to assure that we miss no patients with sepsis.  They highly value any intervention that might decrease sepsis deaths or severe morbidity.   They discount inappropriate antibiotics for “false positives”.  In order to increase sensitivity, you must sacrifice specificity.

Our screens for sepsis have mediocre sensitivity and specificity. Prognostic Accuracy of qSOFA for Mortality | Ann Intern Med | ACP

qSOFA had poor sensitivity and moderate specificity for short-term mortality. The SIRS criteria had sensitivity superior to that of qSOFA, supporting their use for screening of patients and as a prompt for treatment initiation.

Many, include the IDSA, worry about overuse of antibiotics.  They argue that patients with possible sepsis deserve a careful clinical assessment. Infectious Diseases Society of America (IDSA) POSITION STATEMENT: Why IDSA Did Not Endorse the Surviving Sepsis Campaign Guidelines | Clinical Infectious Diseases

Our societies had different perspectives, however, regarding the interpretation of the major studies that informed the guidelines’ recommendations, thus leading us to different conclusions and different perspectives on the recommendations. IDSA consequently elected not to endorse the guidelines. IDSA nonetheless hopes to be able to continue collaborating with the Surviving Sepsis Campaign and the Society of Critical Care Medicine to resolve our differences and to develop further strategies together to prevent sepsis and septic shock as well as reduce death and disability from these conditions both nationally and globally.

It becomes even more complex when we consider the proposed CMS sepsis bundle.  This article – SEP-1 Hemodynamic Interventions | Ann Intern Med – addresses this component.

Conclusion:
No high- or moderate-level evidence shows that SEP-1 or its hemodynamic interventions improve survival in adults with sepsis.

We must hope that this controversy will lead to gathering more information to resolve the controversies and improve care.  Science demands controversy.  Medicine demands that we view everything critically.  My opinions on the controversy are not as important as exposing the controversy.

The tyranny of metrics – a book review

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Category : Medical Rants

From the Amazon web site:

How the obsession with quantifying human performance threatens our schools, medical care, businesses, and government

Today, organizations of all kinds are ruled by the belief that the path to success is quantifying human performance, publicizing the results, and dividing up the rewards based on the numbers. But in our zeal to instill the evaluation process with scientific rigor, we’ve gone from measuring performance to fixating on measuring itself. The result is a tyranny of metrics that threatens the quality of our lives and most important institutions. In this timely and powerful book, Jerry Muller uncovers the damage our obsession with metrics is causing–and shows how we can begin to fix the problem.

Filled with examples from education, medicine, business and finance, government, the police and military, and philanthropy and foreign aid, this brief and accessible book explains why the seemingly irresistible pressure to quantify performance distorts and distracts, whether by encouraging “gaming the stats” or “teaching to the test.” That’s because what can and does get measured is not always worth measuring, may not be what we really want to know, and may draw effort away from the things we care about. Along the way, we learn why paying for measured performance doesn’t work, why surgical scorecards may increase deaths, and much more. But metrics can be good when used as a complement to—rather than a replacement for—judgment based on personal experience, and Muller also gives examples of when metrics have been beneficial.

Complete with a checklist of when and how to use metrics, The Tyranny of Metrics is an essential corrective to a rarely questioned trend that increasingly affects us all.

Jerry Muller, Ph.D. in History, first recognized the metrics problem as a Department Chair.  As he struggled with the many forms the administration wanted, he began to read and learn about the problem.  In this book, he gives a wonderful historical perspective on metrics and “accountability”.   He uses examples from higher education, K-12 education, medicine, policing and business.

Repeatedly he gives examples of the problems of gaming the stats.  The act of reporting and rewarding a statistic almost makes that statistic irrelevant.  The metric focuses attention towards that being measured, and diminishes focus on other issues.

We have written about this often.  We are seeing this now.  I recently participated in two sessions concerning MACRA.  These sessions focused mostly on how to “pass the test”.

The metric designers believe that they are improving quality, yet no studies suggest that even performance improves.  Each study that shows the problems induces the same retort – we are early in the development process for performance measures, we just need better measures.

Muller also writes about the costs of these measures.  In medicine, most practices spend considerable money just to report these measures.

Measures can harm patients.  Rather than focus on a patient’s major concerns, we can become preoccupied with successfully adding to our report card.

While most readers already understand the problem, Muller provides great examples and insights into the discussion.  Hospital administrators, legislators,  insurance executives and governmental rule makers should all read this book.  Sadly, they will continue to believe in metrics despite the rational arguments against most metrics.

Metrics can help us examine our own successes and failures.  Muller gives some great examples of the positive metrics that we develop for ourselves.  He distinguishes such metrics from the “accountability” metrics.

I highly recommend this book.  It will take around 3-4 hours to read but it may induce even more anger over metrics.

Tips for IM attendings – my favorite question – Chapter 22

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Category : Medical Rants

“What do you do for fun?”

That is my favorite question.  And I use it with patients and learners.

With patients, it opens a window to the possibility of anhedonia.  It also helps you understand who the patient is.  Just asking the question often creates a sense that we care about the person who has the disease.

In the outpatient setting you can use the answer on each visit to gauge the patient’s quality of life.  If you have someone who regularly fishes, and then one day no longer goes fishing, you probably have a clue that something serious is wrong.  If they have been fishing, the fact that you asked sends a clear message to the patient.

With learners, again it helps us understand our teammates.  While I do not have data to prove it, having an attending physician who wants to know who you are helps team dynamics.

I ask the question, and then I have another important question on the inpatient service.  After a learner has a day off, I try to ask them how their day went.  What did they do?  And I share my non-medical activities with the team.

While I love medicine, I also enjoy my exercise, golf, music, etc.  I want the learners to see me as a well rounded human being.  They need to see that to keep their goals in perspective.

So try this question.  What do you do for fun?  Do your learners know?  Do you know them?

Tips for IM Attendings – Chapter 22 – take a mental break

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Category : Medical Rants

Currently I am reading a fascinating book – When by Daniel Pink.  Yesterday while flying to the SGIM Annual Meeting, I read a chapter about fatigue and its impact on our focus.

During the reading I reflected on an accidental routine I developed when night float started.  At our post call rounds which start at 7 and are supposed to end by 10 (I really do finish with the learners by then), we first hear the overnight admissions from the night float.  We work hard to keep those presentations to no longer than 1 hour.  We then take a 15 break.  The break allows the team to make some consultant calls, write a few orders, or just chat.  When we resume, the team is ready to go.

Presenting 8 new patients is challenging for any team.  If we presented everyone without taking a break, the team would fall behind on many basic tasks.  They would sit there worried about getting consultations, ordering imaging, etc.

They also need time to move around.  We present sitting, and it usually takes 2 full hours to hear 8 patients (and that means going quite fast at times).  Those 15 minutes are gold.  Almost all residents and interns are very grateful.  But I am also grateful.  I take that time to walk downstairs to get a drink.  I chat with the students or house staff, depending on the day.  When we start back we are refreshed and (I believe) more productive.

Breaks are healthy.  Talking about non-medical issues is healthy.

So think about how you can take a mental break (and perhaps even a physical break) during rounds.  You and your learners will benefit, and therefore your patients will benefit.

 

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