I probably should have started with this topic in my series on overrated medications. The number needed to treat, even if the patient has streptococcal pharyngitis, is about 1 million, higher still if they don’t have strep throat. This makes the doctor using Crestor in primary prevention for patients with normal LDL and elevated hsCRP look like a genius.
It is well-known among physicians that antibiotics are over prescribed. Several conditions come to mind for which antibiotics are often prescribed, but not needed: the common cold, allergic rhinitis, acute bronchitis (bacterial and viral) and acute pharyngitis, also known as the sore throat.
Why do physicians prescribe antibiotics unnecessarily? First, I think there is a subtle pressure. The patient made the appointment because they felt something needed to be done, namely an antibiotic prescribed. When one isn’t prescribed they often complain. In fact, it is not uncommon for a patient to present with a complaint that reads “I need an antibiotic.” Secondly, the physician feels he has shortchanged the patient somehow if he assesses the situation and determines no treatment is needed. The patient made an appointment, spent time away from home or work, and then the doctor does nothing. But let’s not forget, no medication is without side effects and the prime principle of medical ethics is first, do no harm.
Now let’s tackle antibiotics and pharyngitis. Antibiotics have routinely been prescribed for sore throats for over 30 years. Antibiotics have definitely been prescribed for strep throat, but many doctors prescribe them for any sore throat. The reason is that streptococcal pharyngitis is rarely followed by condition known as rheumatic fever and rheumatic fever is sometimes followed by permanent damage to the heart valves. Treating streptococcal pharyngitis with an antibiotic, namely penicillin, will result in fewer cases of rheumatic fever.
How strong is the evidence? If you are a physician, you might be surprised by what you read here. When I discovered it I was very surprised. I became aware of this information reading the excellent book Hippocrates Shadow by David H. Newman, M.D. I recommend it to patients and physicians.
Our story begins in mid twentieth century Wyoming at Warren Air Force Base. Here, according to Newman (1), during the 1940s and 50s military recruits suffered rates of rheumatic fever 1000 times the normal rate. This presented an opportunity for research and the military physicians there discovered that penicillin reduced the rate of occurrence of rheumatic fever from 2% to 1% in recruits with strep throat. They published their results in The Journal of The American Medical Association. Only an excerpt is available without paying a fee.
Since only 2% of the recruits with strep throat developed rheumatic fever, 50 people had to be treated to impact one. But, as Newman points out, Warren Air Force Base was suffering a rate of rheumatic fever 1000 times greater than normal. And that is 1000 times normal for 1950. Since then the incidence has declined further and Newman points out a current incidence of 0.1 per 100,000.
According to Newman, assuming physicians only treat strep positive sore throats, then 1 million antibiotics prescriptions will prevent 1 case of rheumatic fever and cause 2,400 potentially fatal allergic reactions, 100,000 cases of diarrhea and 100,000 rashes.
Some argue that rheumatic fever is in decline because of antibiotic use. Newman argues otherwise and cites improved hygiene, nutritional factors, decreased population crowding, improved preventive care and evolutionary changes in the bacterium. His reference for this is here, but unfortunately only the abstract is available.
Thanks to David H. Newman and his excellent book for making this post possible.
1. Newman, David H., Hippocrates Shadow (New York: Scribner, 2008) 112-115.
Overrated Medications Series: No. 4 Cholinesterase Inhibitors for Alzheimer’s Dementia
Alzheimer’s dementia is a tragic disease and there is no effective treatment for it. Families watch their loved ones become more confused, initially suffering short-term memory loss, then long-term memory loss and finally becoming withdrawn and requiring total care. Eventually patients stop eating and drinking. Along the way many patients become irritable, even violent. Others are docile. Alzheimer’s dementia is a terminal illness and care is palliative. Doctors want to help, offer some hope to families and patients. For that reason they prescribe cholinesterase inhibitors.
Neurons (Nerve Cells) in the brain are separated by very small spaces known as synapses. Acetylcholine is a chemical used by neurons to communicate across synapses. In Alzheimer’s dementia, there is reduced acetylcholine activity due to damage or death of cholinergic neurons. So, according the cholinergic hypothesis of Alzheimer’s dementia, increasing acetylcholine will slow the progression of Alzheimer’s dementia. Cholinesterase inhibitors increase acetylcholine by inhibiting the enzyme that breaks down acetylcholine. Examples of these drugs are Aricept (donepezil) and Exelon (rivastigmine).
This class of drugs work. They work so poorly that not once, never as long as I have prescribed them over more than 10 years, do I remember a patient or their family coming in and telling me that they have noticed any improvement in Alzheimer’s symptoms. I do not recall any physician telling me of their fondness for cholinesterase inhibitors. Normally I would not rely on anecdotal evidence; it is the worst kind of evidence. In this case I think 10 years, no success, is enough evidence. However, since I am a simple country doctor my readers will ask for a bit more evidence. Keep reading.
Here is the abstract from an article from The Lancet titled Long-term donepezil treatment in 565 patients with Alzheimer’s disease (AD2000): randomised double-blind trial. This study showed not even a 1 point change in the Mini-mental Status Exam Score with 2 years of Aricept use. No significant benefit in institutionalization or progression of disability. Compared with placebo Aricept offered no differences in psychological outcomes, deaths or adverse events. The article’s interpretation “Donepezil is not cost effective, with benefits below minimally relevant thresholds. More effective treatments than Cholinesterase inhibitors are needed for Alzheimer’s disease”.
A systematic review of the clinical trials of the cholinesterase inhibitors is found in the British Medical Journal. The conclusion of the authors: “Because of flawed methods and small clinical benefits, the scientific basis for recommendations of cholinesterase inhibitors for the treatment of Alzheimer’s disease is questionable.” This review article pointed out that these medications do in fact work, but that their effect is not clinically relevant. Quoting from the article: “The gains of 1.5-3.9 points in cognitive function, as measured with the Alzheimer’s disease assessment scale, fall below the 4 points that a panel of experts from the US Food and Drug Administration proposed as the minimum of a clinically important effect.”
Given these drugs poor efficacy, why are they prescribed? I think it is because the pharmaceutical industry markets them well. Doctors want to do something to help and there is really nothing else to offer.
Now the risks. The risks it seems are increased chance of permanent pacemaker insertion, syncope and hip fractures in the elderly. The risk was small and amounted to less than 3% increased risk per 1000 person-years for each event mentioned. This was also an observational study and so there may be, in fact, no risk of these things. But for such poorly beneficial drugs, should any risk be tolerated?
I will leave you with costs. After all, if these medications are cheap enough, perhaps we would give them a try.
Aricept 10 mg $2871.60 for 1 years therapy.
Exelon Patch 9.5 mg / 24 hours $2770.68 for 1 years therapy.
Prices taken from Epocrates.com on 4/22/2010.
See Our Country’s Future: A Look at Massachusetts Healthcare
Nicole Kurokawa writing at the Independent Women’s Forum may prove prescient. She says Massachusetts health care reform is very similar to what we will soon face on a national scale. She examines recent events in Massachusetts where the major insurers facing price controls and having suffered $100 million dollar losses are refusing to issue new policies. The Massachusetts government’s solution: they ordered these private businesses to sell their product or face fines and penalties. Is this how business is done in the United States of America? This excellent article is here.
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X-Ray of Hip Fracture
Bisphosphonates are well-known among post menopausal women. Examples of these drugs are Fosamax (Alendronate), Boniva (Ibandronate) and Reclast (Zoledronic Acid). These drugs treat osteoporosis and increase bone density by inhibiting the resorption of bone by osteoclasts. By increasing bone density, they reduce hip fractures and vertebral fractures. The drugs do work. Like the other medications reviewed in this series, they do not live up the hype surrounding them and do not work as well as their relative risk reduction would indicate. The absolute risk reduction tells their true effectiveness, which is small. Furthermore, physicians often prescribe them to women with osteopenia, a less severe form of bone thinning. For osteopenia their effectiveness is even less in preventing fractures, probably zero. Bone density is usually reported as a T-score, a measure of osteoporosis given as the number of standard deviations above or below the mean for a healthy 30-year-old adult of the same sex and ethnicity as the patient.
Let’s look at Fosamax first. A study from The Journal of the American Medical Association is here. Over the 4 years of the study only women with T scores of -2.5 or worse benefited from Fosamax. The absolute risk reduction was 1.2% fewer hip fractures over 4 years in women with severe osteoporosis (2.2% fractures in the placebo group and 1% in the Fosamax group). Therefore the approx. number of patients needed to treat (NNT) for 4 years to prevent 1 hip fracture is (100 / 1.2) = 83 (actual NNT = 81). This small 1.2% reduction over 4 years (0.3% per year) is boastfully reported by the Big Pharma reps as a 56% reduction in hip fractures. 56% is the relative risk reduction and exaggerates the effectiveness of the drug. It does not tell the patient the benefit they will get from investing their hard earned money in the drug.
Now let’s look at Reclast. This drug is very popular based on the requests for it I receive. Here is the article covering Reclast. Absolute risk reduction in hip fractures was 1.1 % for women with T scores of -2.5 or worse. NNT therefore is about 91 over the 3 years of the study. There is one adverse reaction worth mentioning: serious atrial fibrillation (see table 3 in the article). Serious atrial fibrillation occurred in 0.8% of the patients giving a number needed to harm (NNH) of (100 / 0.8) = 125. This is not far from the NNT to prevent the hip fracture.
An argument I hear from the Big Pharma reps (and physicians) pushing these drugs is that hip fractures carry a significant 1 year mortality rate. This is true. The 1 year mortality rate after a hip fracture ranges from 15 to 50% depending on the patient. Since bisphosphonates reduce hip fractures, I suppose the logical conclusion they wish for me to make is that bisphosphonates reduce mortality. This ain’t so. Once again look at table 3 in the Reclast article and notice 3.4% of the Reclast patients died versus 2.9% of the placebo patients. Slightly more deaths in the Reclast group. This was not statistically significant, but is relevant. Reclast costs $1,137.18 per dose, or $310,401 to prevent 1 hip fracture and no deaths.
For Fosamax and Reclast to be efficacious, women must take their calcium and Vitamin D supplements. Some brag of Fosamax’s once weekly dosing and Reclast’s once yearly dosing as enhancers of compliance. However, if the patient does not take her calcium and vitamin D, very likely all benefit will be lost.
Trabecular Bone
Finally, there is evidence that using these drugs over the long run can increase the risk of femur fractures. The drugs do not build trabecular bone (the scaffolding of bones) but rather they build cortical bone. According to some studies bones become more brittle with bisphosphonate use leading paradoxically to more fractures after prolonged use. About 2 years ago the FDA cleared these drugs free of this concern, but is now re-investigating them. For more on this see here and here and here.
I can get behind Reclast in certain situations. If a patient suffers a low trauma hip fracture and receives a Fosamax infusion within 90 days, it will improve survival and reduce future fractures. The effect is real and the NNT is reasonable. The proof is here in a study titled Zoledronic Acid and Clinical Fractures and Mortality after Hip Fracture published in the New England Journal of Medicine. In this specific case the NNT to prevent 1 death is only 27 and NNT to prevent another hip fracture was only 66 (of course there was only 1 hip left to fracture). Length of the study was 1.9 years. This study has received some criticism for relying on composite end points.
Another bisphosphonate, Actonel (Risedronate) also seems to work best when given to women after they have suffered an event. Looking at this article from February 1, 2001 NEJM you can see looking at table 2 that if women have suffered a prior vertebral fracture, then Risedronate is very effective reducing hip fractures from 5.7% to 2.3% over the 3 years of the study. This gives a very respectable NNT of 29. Otherwise, the NNT was 167. Serious adverse events were slightly higher in the placebo group.
It seems bisphosphonates, like statins for coronary artery disease, are best used in patients who have already suffered an event. In seems reasonable to use them in that situation. In fact after more research on bisphosphonates, I think I might have been a bit hard on them. I do think they are over prescribed and offer little benefit unless patients are carefully selected.
Overrated Medications Series: No. 2 Statins For Primary Prevention of Cardiovascular Diseases
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Diseased Coronary Artery
Facts are stubborn things, but statistics are more pliable. — Mark Twain
This post is blasphemy. Fortunately I am in good company. I offer nothing new here for well read physicians and patients. I have no original ideas to present. My hope is to help spread the word. I, like most primary care physicians, had the “statins are good, add them to the drinking water” mentality drilled into my head at lectures paid for by Big Pharma. Eloquent cardiologists with rapier wit expounded on the studies while I dined on filet mignon and pinot noir. I left the lectures after hearing impressive risk reduction numbers like 33% for cardiovascular death and 22% for all cause death. What I didn’t learn was the difference between the relative risk reduction and the absolute risk reduction and concepts like number needed to treat. Like most family physicians (and other specialists I suspect) I never read the actual studies. I just accepted what the speakers paid for by Big Pharma told me. I woke up when I read two books which I recommend to you: Worried Sick by Nortin Hadler and Overdosed America by John Abramson. If you can let go of your emotions and be objective these books are splendid road maps for skeptical patients that are proactive for their own health.
Statins are drugs which lower cholesterol levels by decreasing cholesterol synthesis in the liver. I think every American knows these drugs. To name a few: Lipitor, Pravachol, Crestor and Zocor. Plaques in coronary arteries are largely composed of cholesterol. Lowering cholesterol will in theory and in fact cut the rate of formation of plaque and in some cases shrink plaque.
There are two kinds of heart disease prevention. In primary prevention statins are given to people without known coronary artery disease to prevent heart disease or heart attack. In secondary prevention statins are given to people with known coronary artery disease or those who have had a prior heart attack to prevent another heart attack (in some cases a first heart attack). There is a big difference between the two. Primary prevention has little benefit, secondary prevention has great benefit.
Let’s start with the most well-known statin study of all: The West of Scotland Coronary Prevention Study. The patients in this study had very high cholesterol levels with a total cholesterol averaging 272 mg/dl and an LDL (bad cholesterol) averaging 192 mg/dl and an HDL (good cholesterol) averaging 44 mg/dl. There were 6,595 subjects in the study, about half received Pravachol and half placebo. 44% of the patient’s smoked and 16% had high blood pressure. (If I may pontificate, smoking is a far greater risk factor than high cholesterol and smoking cessation is of far more benefit than taking a statin). After almost 5 years the relative risk reduction of all cardiovascular deaths was 32% (statistically significant) and relative risk reduction of all cause death was 22% (not statistically significant, but close). Sounds impressive, yes. But absolute risk reduction of all cardiovascular death was only 0.7% and absolute risk reduction of all cause death was only 0.9% over 4.9 years (see chart). Thus, 100/0.7 = 142 men have to take Pravachol for nearly five years to prevent 1 cardiovascular death and 100/0.9 = 111 men have to take Pravachol for nearly 5 years to prevent 1 death overall. The study itself sums it up: “it can be estimated that treating 1000 middle-aged men with hypercholesterolemia and no evidence of a previous myocardial infarction with pravastatin for five years will result in . . . 7 fewer deaths from cardiovascular causes, and 2 fewer deaths from other causes than would be expected in the absence of treatment.”
The reason I started with the West of Scotland Study is because it supports statin use more than any other primary prevention study I know of. The patients in this study were very high risk, yet the intervention did not help much. Subsequent studies have not done even as well as the West of Scotland Study. Some studies have found no benefit from statins in primary prevention.
Here is another statin study, the AFCAPS/TexCAPS study. Read through it. Here is a quote directly from it, copied and pasted: “The overall mortality rate was similar in each group, with 80 deaths among participants treated with lovastatin and 77 deaths among participants treated with placebo (4.6 and 4.4 per 1000 patient-years in participants treated with lovastatin and placebo, respectively).” Were you able to find that quote? Hard to find isn’t it? Wonder why? Why wasn’t a statistic as important as overall mortality included in the abstract? Is my thinking on the subject wrong? If overall death rates are equal, does it matter what the cause of death is?
Here is another statin study, the PROSPER study published November 23, 2002. This study looked specifically at the elderly. It was sort of hybrid study as the participants were a mixture of people with known coronary artery disease and no known coronary artery disease. Patients were also generally high risk for coronary artery disease. Approx. 25% smoked, ~10% had diabetes, ~25% had angina and ~13% had prior heart attacks. The PROSPER study is available on-line from The Lancet and is free, but you will need to register an account to read it. Although not mentioned in the abstract, here is a quote directly from the article: “There was no observed difference in all-cause mortality.” Once again I ask, if mortality is the same in both groups, does it matter what the cause of death is?
Here is a meta-analysis that agrees with me.
Read my Crestor post.
I’m going to stop now and let my readers look into it further on their own. Read the primary prevention studies, like ALLHAT. Forget the relative risk reduction, look at the actual percentage differences between the treated and placebo groups. Divide the difference into 100 and you will get the number needed to treat over the length of the study. Notice if the abstract mentions overall mortality; if it was favorable it will always be mentioned. If unfavorable it might be buried in the article.
Another point I would like to mention is that the writers of the National Cholesterol Education Panel (NCEP) guidelines have financial ties to Big Pharma. This explains some of what you have read here. Still, I do follow the NCEP guidelines. The guidelines are actually reasonable. With Framingham risk calculation and stratification based on family history and coronary disease equivalents, I find I prescribe statins a lot less often than I did in the days when I just looked at a patient’s cholesterol levels and guessed. I also give patients the number needed to treat. A math professor declined treatment based on that once.
Don’t forget, we’re talking primary prevention here. If you are very high risk, middle-aged and known to have coronary artery disease, then this does not apply.
Also don’t forget I’m not your doctor. This is not health advice. This is information for those interested in heath and well-being, but you need a face to face encounter with a physician and an exam and history and physical before making any decisions about medications or treatment.
Cetaphil Skin Cleanser For Head Lice
Head Louse
I was delighted to find this benign treatment for head lice on a blog titled Well at The New York Times. This is legit and published in the journal Pediatrics. The protocol explained in the article gives a cure rate over 3 weeks of 95%, exceeding that of more toxic treatments like Malathion. I look forward to giving it a try in the right situation.
Overrated Medications Series: No.1 Weight Loss Medications
This is the first in my series on overrated medications. I am not trying for a definitive ranking of these medications, but rather I am simply trying to show my readers some of the most hyped and overrated drugs on the market. It will help people make better decisions, avoid waste and improve their health.
For number one I choose weight loss medications. The reasons are:
1. Weight loss medications are ineffective in the long run.
2. If they are ineffective, then by definition their therapeutic index (margin between safety and effect) is suspect.
3. Some are outright scams.
4. They are rarely needed (there are perhaps a few exceptions).
The most successful weight loss medications were fenfluramine and phentermine (Fen/Phen). This combination made a huge impact in the 1990s. Weight loss clinics sprang up and small fortunes made. I admit to taking the medications myself and to prescribing them. I bought into the hype.
The Fen/Phen studies were by Michael Weintraub and published in Clinical Pharmacology and Therapeutics. Initial results for some patients were astounding. Weight loss of 50 pounds the first year was fairly common. By year 3 of the study, study subjects were regaining lost weight and average weight lost was only 11 pounds. More than 50% of the patients had dropped out. I might add that this 11 pounds includes the medications plus diet and exercise. The United States Preventive Services Task Force guidelies for obesity cite 6 studies showing only diet and exercise resulting in up to 9.9 pounds of weight loss over 24 to 84 months. So medications add little to the small amount of weight lost by diet and exercise alone.
The Fen/Phen boom ended when fenfluramine patients developed valvular heart disease and pulmonary hypertension, both potentially lethal.
There are only two drugs currently approved for long-term use for obesity: Orlistat (Alli) and Sibutramine (Meridia). Neither of these drugs is more effective than the Fen/Phen combo. Orlistat is probably safe. It blocks the absorption of 25% to 30% of ingested fat in the intestine. Side effects are gas, bloating and loose oily stools to a degree that many users soil their underwear. You can decide if those side effects are worth it for the small weight loss effect.
Sibutramine is prescription only weight loss medication. I consider it unsafe. In this respect I disagree with the FDA, though they are conducting a safety review. The European Union has suspended Sibutramine stating risks do not outweigh benefits. It does not result in more effective weight loss than Fen/Phen and can raise blood pressure and increase cardiovascular risks.
Other weight loss medications include Phentermine alone. It is generally safe if patients are carefully selected and monitored. But why bother with this medication? It is approved only for short-term use. Weight is regained once the medication is stopped. The medication’s weight loss effects, just like those of Fen/Phen fade over the long run. It is of the amphetamine class and has some addictive and abuse potential. Side effects are high blood pressure, anxiety, palpitations, fast heart rate and in rare cases seizures.
Lastly I will mention the hormone Human Chorionic Gonadotropin (hCG). Marketed as Releana, it is a scam. Click the link to their slick site, scroll down and read the FDA disclaimer at the bottom of the page: FDA has not approved hCG for weight loss and there is no substantial published evidence hCG is effective in obesity treatment. Then click their “Help and Support” tab and then “Clinical Studies.” Open the second PDF file and go to page 5, under the results section you will read “Regarding weight loss, similar results (with/without hCG administration) were obtained.” You have to dig for it, but at least they are honest. The hCG does nothing. It is the 500 calorie per day that gets the job done. If you want to pursue a 500 calorie a day starvation diet, that’s your business. But you need medical supervision. It can be unsafe. It can rarely result in electrolyte abnormalities and sudden death. You will lose lean tissue, that is muscle as well as fat, and you will regain lost weight. Releana is a scam.
Do you need to lose weight? If your body mass index (BMI) is greater than 35 weight loss would probably improve your health. A BMI of 35 would put you in the fattest 3% of the population. A BMI from 18.5 to 24.9 is considered normal. Surprisingly, to those not well-informed on obesity, a BMI of 25 to 35 carries no increased risk of death. Until BMI exceeds 35 (and that includes 35 and up to 60+) there is simply no mortality risk associated with obesity. In fact, mortality is lower in the overweight until BMI exceeds 35.
There are several drugs in the pipeline for obesity. I will review them in the future. Preliminary reports show some promise, but weight loss is modest as it has been with all past drugs. Except for those rare patients that truly need to lose weight for health reasons I recommend healthy eating (not dieting) and exercise and for patients to accept their current weight. I recommend that my fat patients read Health at Every Size by Linda Bacon.
ACCORD BP Study Shows Best Guesses by Experts Wrong
The Action to Control Cardiovascular Risk in Diabetics (ACCORD) study shows that intensive blood pressure control with a target of 120 mmHg is of no benefit in reducing fatal and nonfatal cardiovascular events. Results were released at the American College of Cardiology’s Scientific Sessions in Atlanta Georgia and published online in the New England Journal of Medicine. These results conflict with the advice given to physicians in the JNC 7 guidelines recommending a systolic BP below 130 in type 2 diabetics.
Many physicians have felt that piling on medications in elderly diabetics to meet these goals was possibly harmful. Unintended consequences could be the very real harm of polypharmacy and drug side effects. However, to meet “quality” standards some physicians followed the guidelines anyway. Other, perhaps more thoughtful physicians, made their decisions on a case by case basis. For more on my thoughts about this sort of thing, go here.
From HeartWire explaining the thoughts of Dr. William Cushman about the ACCORD study and the JNC 7:
The ACCORD BP trial was conducted because there was no clinical-trial evidence to support recommendations to lower systolic BP below 130 mm Hg in type 2 diabetes—as is advised in the JNC 7 guidelines—Cushman explained. Instead, this recommendation was based on observational studies and “best guesses” by experts.
There was a significant reduction in strokes with 89 people treated for 5 years to prevent 1 stroke. Rates of death from any cause were actually slightly higher in the intensively managed group 1.28% per year versus 1.19% per year.
Coumadin and Tooth Extractions
On several occasions dentists have asked that I stop patient’s Coumadin prior to dental extractions. I have always complied with this request. However, a cardiologist told one of my patients this was not necessary. I decided to investigate this and found it true. Extractions while on Coumadin are very safe, even if INR is above 3.0. I do not think this is widely known as I mentioned this to several colleagues and they were unfamiliar with this. In fact another cardiologist even thought it unsafe. In any event here are the links and you and your patient can decide for yourselves:
Lack of a scientific basis for routine discontinuation of oral anticoagulation therapy before dental treatment
Safety of Outpatient Dental Procedures For Patients on Coumadin
mammogram image
For years now, I have routinely referred my female patients of age 40 years and older for mammograms. I have actually known for some time that evidence of benefit was weak. But, like most physicians, ordering the mammograms was habit and my patients expected it. When the US Preventative Services Task Force (USPSTF) released their recommendations against routine screening for women under 50 years of age in November 2009 I decided to look into the evidence a bit. The Cochrane Reviews cover it well and here is an excerpt:
for every 2000 women invited for screening throughout 10 years, one will have her life prolonged. In addition, 10 healthy women, who would not have been diagnosed if there had not been screening, will be diagnosed as breast cancer patients and will be treated unnecessarily. Furthermore, more than 200 women will experience important psychological distress for many months because of false positive findings.
It is thus not clear whether screening does more good than harm. Women invited to screening should be fully informed of both the benefits and harms.
So, 2,000 women x 10 years = 20,000 mammograms to save one life. Ten times as many women undergoing unnecessary treatment. At www.cochrane.dk you can download an evidence based leaflet for your patient’s to read. It is excellent.
One reference, The Canadian National Breast Screening Study. This study involved over 100,000 mammograms (~25,000 women over 4-5 years, 11 to 16 years of follow-up) and showed no reduction in mortality with mammograms compared to breast exams alone. It is worth reading.
Stephen A. Feig writing in an editorial in the Journal Cancer in 1996 estimated that for every 10,000 women screened for 10 years with mammography there is one case of cancer caused by radiation exposure. This, I suppose, verges on the trivial; 1 case of cancer per 100,000 mammograms. But for a test that may offer no benefit, it is worth a mention to the patient.
Now I review both the potential benefits and harms of mammograms with my patients. I present the USPSTF recommendations. I tell them the American Cancer Society disagrees. I give them the statistics from the Cochrane review. I take a family history. An early history of breast cancer in a first degree relative will always sway me in favor of the mammogram.
I have found so far that about 50% of my patients have declined mammogram screening when they have all the facts. Isn’t it my job to give them all the facts?
