Tim Russert - Heart attacks, calcium scores, regressions, and life-saving lessons
(Originally posted in 2008)
Tim Russert, the moderator of NBC's Meet the Press program and head of its Washington, D.C. news bureau, died suddenly of a heart attack on June 13, 2007. It's a tragedy, especially for his family and friends. But it also offers an important - perhaps a life-saving - lesson for the rest of us. And it's also a good excuse to do a regression!
Russert's heart attack shouldn't have come as a surprise to anyone familiar with his medical condition - his heart was a land mine ready to go off for any reason, or for no reason. In fact, it's almost surprising that he hadn't already had a heart attack! More below.
First, the lesson:
Everybody should have a Calcium Scoring Test, men at about age 50 and women at about age 55. The results of the test should be used to guide lifestyle and medication decisions.
Next, quibbles and comments:
1. The information in this blog is based on news reports. I have no first-hand knowledge of any of the data. Russert's physicians and family have not released a full report - it's even possible there are ongoing financial negotiations about the apparently less-than-optimum care Russert received.
2. I have absolutely no financial connection to any company that has anything to do with Calcium Scoring Tests.
3. I'm a Ph.D. chemist/physical chemist/biochemist/retired chemistry professor, not an M.D. M.D.s are constrained by community standards of care and what is regarded as standard practice - and standard practices tend to change very slowly. If a physician suggested to his/her patients that a Calcium Score is more important than the patient's cholesterol level, the physician could be considered to be guilty of malpractice if the patient subsequently had a heart attack.
4. Whether the "baseline" test is done at age 45 or 50 or 55 (for men) probably isn't terribly important. For men with high risk factors (bad family history, high cholesterol, etc.), 45 is probably better. And similarly for women. The idea is to have the test before the Calcium Score (and plaque development) has become irreversible.
5. Very few physicians pay much attention to Calcium Scoring Tests. This is a situation where the patients have to lead the doctors.
6. Any time a physician tells you that you need to lower your LDL (bad cholesterol) to less than 75, say, "What about Tim Russert?" (This doesn't mean, of course, that cholesterol is unimportant heart-wise. What it does mean is that there are other important factors, one of the most important ones being the Calcium Score.)
7. For people who know nothing about Calcium Scoring Tests: The test is a CT-type X-ray that shows the degree of calcification in the coronary arteries. When plaque builds up in the arteries and sits around for a while, calcium builds up in the plaque. The amount of calcium is then a marker for the degree of atherosclerosis in the arteries, and is a reasonably good predictor of heart disease. There are several links at the end of this blog about the test. Facilities to give them are probably in every metropolitan area. Most insurance companies won't pay for them, because they're still considered experimental (at least, the insurance companies consider them to be experimental, even if the recent medical literature considers their usefulness an "answered that" question). As mentioned earlier, standard medical practice changes slowly, especially if there's money involved. The test is absolutely painless, except in the wallet.
8. What should you do after you have the Calcium Scoring Test and get the results? Talk with and try to educate your physician. If you have a high number (for example, higher than the median for your age), try to do something about it: Lose weight, improve your diet, exercise, and so on.
9. Will lifestyle changes stop the calcification? If a person has his/her first Calcium Scoring Test at a later age and the results are bad, will it be too late to do anything? These are questions to which there are no firm answers - the test is too new for enough patients to have been followed for long enough, and there simply aren't enough good data. What is for sure is that it's better to have bypass surgery or a stent insertion on an elective basis rather than in the middle of or after a heart attack.
Now, more about Russert.
1. Russert had a Calcium Scoring Test in 1998 when he was 48, and had a Calcium Score of 210. This put him well above the 90th percentile for his age, and corresponded to a "moderate" heart attack risk. "Moderate risk" - ho, hum.
2. The important point is that Calcium Scores increase roughly 22% (typically, 15%-30%, depending on the individual) per year, corresponding to doubling every 3-5 years (see the Regression Lesson at the end). That is, suppose your score is 10 at age 45. If it doubles in 5 years your score will be 20 at age 50, 40 at age 55, and 80 at age 60, and so on. In Russert's case, a score of 210 at age 48 would correspond to a score of about 800 (doubling every 5 years) to 1800 at age 58 (doubling every 3 years) - most likely, about 1500. All of these are very high numbers, and are far beyond "moderate" risk levels. A recent Calcium Scoring Test very likely would have shown him to be at very high risk for a heart attack.
3. In fact, it's almost surprising that Russert hadn't already had a heart attack. His probable Calcium Score of 1500 or so at age 58 would put him in a very high-risk category, with about a 15% chance per year of having a heart attack (depending on the study one looks at, his chances per year might have been 5%, or they might have been 50% - there's no firm number yet, so we'll take 15% as a reasonable estimate). Let's suppose his risk at age 47 was 0% (meaning no chance of having a heart attack between age 47 and 48). Then we'll suppose his chances increased by 1.5% per year: a 1.5% chance between age 48 and 49, 3.0% between 49 and 50, up to a 15% chance between 57 and 58. The cumulative probability for him having a heart attack between ages 48 and 58 is about 60%. That is, it's not surprising that he had a heart attack by age 58; it's almost surprising that he didn't have one sooner. (See Cumulative Probability below for details.)
4. Unfortunately, his physician, like most physicians, clearly did not put much stock in the results of the Calcium Scoring Test, and instead put the emphasis on medication. The mantra these days is to lower cholesterol levels, mainly using statins such as Lipitor. (Statins are associated with muscle problems, liver problems, and mental problems; but that's a subject for another day.) This process was quite successful for Russert: his LDL (bad cholesterol) level was 68, which is an outstandingly good number. Also, his blood pressure was treated with medication, and was 120/80.
His physician was reported to have said that Russert's heart condition was well controlled with medication and exercise. This statement will not go down in medical history as a great moment, and is roughly equivalent to the old saying that "the operation was successful even though the patient died."
5. Russert's Calcium Score at age 48 should have been more than a red flag for him and his physician. It should have been red flashing lights, sirens, and flares. He should have been given very strong advice to change his lifestyle completely - or at least as much as humanly possible given his position. Weight loss, exercise, more relaxation, and so on should have been mandatory. And regular follow-ups, including Cardiolite or equivalent tests, could have well shown when intervention (bypass surgery or angioplasty with insertions of stents) would be required.
Whether lifestyle changes, follow-ups, and/or surgical intervention would have done the job and kept him alive longer is impossible to know. Russert may have had a genetic condition that pre-disposed him to a fatal heart attack. But if the information from the Calcium Scoring Test had been properly used, at least he and his physicians could have said they did the best with the cards he was dealt. The understatement of the day: They didn't.
Once again, here's the lesson:
Everybody should have a Calcium Scoring Test, men at about age 50 and women at about age 55. The results of the test should be used to guide lifestyle and medication decisions.
If you follow this lesson you'll be able to say you did the best you could with the cards you were dealt - even if you're hit by a bus as you leave the Calcium Scoring Test facility!
Here are a few links about Calcium Scoring Tests.
http://www.mayoclinic.com/health/heart-disease/HB00015
http://www.heartsavers.md/index.html
http://www.americanheart.org/presenter.jhtml?identifier=10000015&q=calcium+scoring&x=24&y=6
http://brighamrad.harvard.edu/patients/education/ct/ctguideheart.htm
There are lots more, and many, many articles saying that Calcium Scoring Tests are very useful - even though they haven't made it into standard medical practice.
Currently, a test costs about $500. However, substantial discounts are often available, for example, if a spouse or relative has had a test. Mine cost $200 because a relative had recently had a test. A suggestion: Get 5 or 6 people to go in together for testing, and ask the facility what they can do for you price-wise.
Of the six or so people I know who have had tests in about the last year, one had a high score, further evaluation, and eventual bypass surgery. Others with relatively high scores are trying to modify their lifestyles. I'm using the results of mine mainly to fight off physicians who say I should take statins to lower my cholesterol level (varying from year to year from about 180 to 220, but I have no significant risk factors for heart problems).
Regression Lesson for the Day
Here are the median (50th percentile) values for the Calcium Score for asymptomatic males as a function of age:
(The "Log" represents the base-10 logarithm of the calcium Score; base-e logarithms are more familiar to scientists but less familiar to everybody else.)
Age............... Calcium Score...................... Log (Calcium Score)
45..................... 3............................................ 0.48
50.................... 5............................................. 0.70
55................... 22............................................ 1.34
60................... 70............................................ 1.85
65 .................160............................................ 2.20
70................. 300............................................ 2.48
The Calcium Score clearly doesn't increase in a straight line (linearly) with age; in fact, it increases exponentially with age. Draw a graph of Calcium Score versus Age - that's nothing like a straight line. If you crank up your Regression Machine and regress Calcium Score against age, you'll find a slope of about 11 and - more important - a correlation coefficient (R-square) of 0.83, indicating a relationship, but not a good linear one, between Age and Calcium Score.
Let's do a better job. To a good approximation, the logarithm of the score increases in a straight-line fashion with age. Draw a graph of Log (Calcium Score) versus Age - not all that good a straight line, but close enough to be useful.
Crank up your Regression Machine and regress Log (Calcium Score) versus Age. For these data, you'll find:
Slope = 0.086 (standard error of 0.006 - a good fit)
R-square = 0.98 (a quite-good linear fit)
It turns out that - isn't this fascinating! - the slope of the regression line is the reciprocal of the number of years it takes the Calcium Score to increase ten-fold (in this case, about 12 years). With a little math, you can show that the number of years it takes the Calcium Score to double is 0.30 divided by the slope, in this case about 3.5 years.
You can do the math to show that in ten years the Calcium Score should increase by about a factor of 7. That's why we would estimate Russert's Calcium Score to be roughly 1500 in 2008, ten years after his first test in 1998.
A comment: This slope and doubling period is for the median. People at a higher (worse) percentile tend to increase more slowly, either because that's how the body works for them or because the people with higher numbers tend to die off.
Cumulative Probability
Let's suppose Russert's chance of having a heart attack between age 48 and 49 was 1.5%, increasing by 1.5% per year. That is, his chance of not having a heart attack between age 48 and 49 was 97%. We'll also suppose that his chances increases by 1.5% per year, to be close to 15% between ages 57 and 58 (the 15% figure is about what would have been expected, based on his projected Calcium Score). Here are the figures:
..................Chance of .........Chance of NOT ...........Cumulative Chance of NOT
Age ..........Heart Attack ...Having Heart Attack ..Having Had a Heart Attack
..................at that Age........at that Age...................by that Age
48 to 49......1.5%......................98.5%...................................98.5%
49 to 50......3.0%.....................97.0%.................................. 95.5%
50 to 51......4.5% .....................95.5%.................................. 91.2%
51 to 52 ......6.0% ....................94.0% ..................................85.7%
52 to 53 ......7.5% ....................92.5%................................... 79.3%
53 to 54 ......9.0% ....................91.0% ..................................72.2%
54 to 55 .....10.5% ...................89.5% ..................................64.6%
55 to 56 .....12.0% ...................88.0% ..................................56.9%
56 to 57 ......13.5% ...................87.5% ...................................49.2%
57 to 58 ......15.0% ...................85.0% ..................................41.8%
The cumulative chances are calculated by multiplying the number for the previous age by the chances of not having a heart attack that year (converted from a percentage to a decimal). For example, the 72.2% figure for ages 53 to 54 is the chance of not having a heart attack before that age (79.3%) times the chance of not having a heart attack in that year (91%). For Russert, the cumulative chance he hadn't had a heart attack by age 58 was only 42%, meaning that, statistically, there was about a 60% chance he would have already had a heart attack. By the time he was 56, he had at least a 50% chance of already having a heart attack and was living on borrowed time.
That's all for now.
