Showing posts with label stent. Show all posts
Showing posts with label stent. Show all posts

Diagnostic Cascade: A Cautionary Tale



Today’s managing health care cost indicator is 2.8 million


I was at a celebration of the end of the academic year last night at Harvard School of Public Health, and a former student told me a cautionary story.

She mentioned that her dad is very careful about his diet – ever since he had a CT-angiogram that showed calcium – indicating a high likelihood of heart disease.    He had no symptoms –and had the test because a friend, a radiologist, had this new machine and offered to test it on him.

2.8 million Americans were expected to get coronary CT scans in 2009. 

I listened, and mentioned that although her dad got radiation he shouldn’t have gotten –since the test was inappropriate – at least it led him to change his diet and make his life healthier.  (The likelihood of cancer due to the radiation from this exam is about 5 per 10,000 for a 60 year old man – but would be substantially higher for women). 

Alas, she told me, the story was much more complicated.

Based on the CT scan results, he had a cardiac catheterization, which demonstrated blockage of multiple vessels.  He had stents inserted, and was discharged home promptly. 

Then, the trouble started.   

He had bleeding and pain from the femoral artery – where the catheter was inserted for his procedure.  He had multiple exploratory surgeries for this – and eventually an errant stitch was removed. He was readmitted to the hospital multiple times over a period of almost half a year for a variety of complications from the stent placement – including one episode where he fainted just a few hours after his initial discharge.  He limped for years afterward.

My student’s dad is doing well now – he’s had no angina, and he watches his diet carefully and exercises.  

But at multiple levels, the health care system failed him

·       He had an initial screening test that was not indicated – since he had no symptoms of cardiac disease.  Here’s a link to a NEJM editorial about coronary CT scanning. 
·       He had a procedure to fix the incidentally-found asymptomatic heart vessel blockages. There is no evidence that a procedure to open up heart blood vessels prolongs life, but such procedures do relieve symptoms of angina – which he did not have. 
·       An error was made during his catheterization, leading to multiple complications which had a profound impact on his life.

If you’re wondering, the cardiologist who apparently made the medical error never apologized.   A subsequent surgeon explained that there had been a medical error, and then denied he said that. 

Anecdotes don’t usually make good policy – but this is a great example of a diagnostic cascade.  An initial ‘noninvasive’ test suggests unexpected disease – and it’s hard for clinicians and patients to stop until the disease (or the patient) is vanquished.  

The personal cost of misuse of medical technology to my student’s father was enormous.  The cost of his health care misadventure was pretty large too.

Disconnect between knowledge and clinical practice

Two articles published this past week demonstrate that there is a striking disconnect between publication and dissemination of knowledge.

Last week, the Wall Street Journal had an article on angioplasty with stents.   The COURAGE study in the New England Journal (2007)  showed that angioplasty (WSJ estimated cost $15,000) gives slightly quicker relief from chest pain of angina, but does not lower the risk of heart attack or death.  In fact, the stock price of Boston Scientific went down by 23% the month the study was published.   However, the rate of angioplasty has continued to increase after a brief dip.   The evidence was in – but this did not lead to a change in practice.


The Wall Street Journal conclusion is that comparative effectiveness doesn’t work.  I think this shows it didn’t work – not that it can’t work.

Yesterday’s New York Times  has an article about the rapid adoption of the daVinci robot to do prostate cancer surgery.  In fact, the only study done shows that those getting laparoscopic or robotic surgery appear to have more incontinence and erectile dysfunction than those who have traditional “radical” prostatectomy.   (This study combines laparoscopic and robotic surgery, and infers complications from claims) The urologists focus on a 40 year-old policeman who was able to have sex a few days after his procedure. Men facing prostate cancer find that heartening, but this is an unusual prostatectomy patients whose experience is not generalizable to most such patients.  This anecdote is certainly not enough to be the foundation for public policy.

What gives?

Periodically, we hear complaints that it’s difficult to disseminate innovation in health care.  I’d say that this is the wrong diagnosis.  Innovation is speedy when it leads to higher profits and more margin opportunity. That’s the case study of the daVinci robot for prostatectomy.  Dissemination of innovation and knowledge is painfully if that knowledge leads to lower margins and less profit opportunity.  Hence, the message that angioplasties with stents don’t offer that much benefit to those with stable coronary disease has little influence on clinical practice.

Should we give up on comparative effectiveness research?

Absolutely not.

It’s critical that we have evidence to determine what is best practice.   We also need to align payment with evidence-based medicine.   We need to decrease the profit margins of procedures with unclear incremental benefit. This is not easy to do, of course.  Cardiologists,hospitals and medical device makers don’t want to lose margin of angioplasties, and they will argue forcefully that angioplasties are far better than medical therapy for a select group of patients – those with unstable angina or acute evolving heart attack.  That argument is correct, and perhaps we need different fees based on diagnosis since the value is different based on diagnosis.

Similarly, urologists and hospitals will argue, correctly, that for surgeons with a long track record of performing robotic surgery – that method is indeed likely to be better, and can even decrease resource cost by saving OR time.  (Most surgeons, with less than a hundred of cases behind them, take more time with robotic surgery. It’s likely that the ‘learning curve’ is one of the reasons that the robotic surgery study results were so disappointing.)  Some might suggest differential payments for surgeons based on their volume – but frankly that’s complicated and might encourage aggressive surgery recommendations.  My preference would be a bundled rate –and if the hospital and physician feel that a high-capital-cost item will be worth it – they can spring for it. 

The issue of high fixed costs and low marginal costs with new technology also looms large.  Once a hospital has a daVinci robot, there are very few incremental costs associated with increased volume. Therefore, once technology is in place, it is highly likely to be used.

We need to do more research on comparative effectiveness, disseminate the results quickly and effectively, and consider results was we design payment and incentive systems to drive more value for our patients and for health care purchasers.

By the way, the governor of Massachusetts has announced a wide-ranging plan to regulate health care cost increases. I'll be planning to blog on that later in the week.