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Periodontal Disease and Atherosclerosis: Another Observational Study Conclusion Disproved

Another widely accepted dogma that comes from observational studies alone was shown to be just our eyes fooling us when surprisingly this week the American Heart Association released an unusual scientific statement with the conclusion that the evidence does not support gum disease as a risk factor or as a cause of cardiovascular disease.  For over 20 years it has been widely believed that periodontal gum disease is a risk factor and a cause of coronary heart disease and stroke.  The story of how the dogma that poor oral health became nearly universally accepted as a risk factor of cardiovascular disease is worth looking at because it exposes the risks of accepting data from an observational study as true just because it seems to make sense and conform to what we also see in practice.

Essentially all of the evidence used to support the belief that gum disease is a risk factor or a cause of atherosclerosis was from observational studies.  In an observational study it is observed that condition A is present more often in people with condition B than in persons without condition B.  Many studies showed that patients who had heart attacks are more likely to have bad oral health than patients who have not had heart attacks.  This is far different from saying that gum disease causes heart attacks.  In an extensive evaluation of all of the studies showing a relationship between gum disease and cardiovascular disease a panel including both dentists and physicians concluded that the evidence simply does not support the conclusion that there is a causative relationship. The problem appears to be that several other risk factors for cardiovascular disease are also put patients at risk for gum disease.  These include tobacco use and low socioeconomic status, as well as age and diabetes mellitus.  In a controlled study these confounding variables would be considered and “controlled” for in any analysis.  In an observational study this is much more difficult to take into account

The association of periodontal disease and atherosclerosis was so in synch with our bedside observations that it was intuitive to accept the association as dogma. For me at least it never occurred to seriously question the relationship. This was in part because of the widespread acceptance of the test hsCRP (highly sensitive C-reactive protein), a test for low-grade systemic inflammation as an independent risk factor for coronary disease.  It was easy to infer that because periodontal disease is a chronic inflammatory condition, can lead to bacteremia, and is a potential cause of systemic inflammatory marker elevation, that is “just made sense” that it is a cardiovascular risk factor.

I hope this 20 year walk down the path of least resistance is one I and others will remember when presented with an observational study purporting to show a relationship. Although I tell patients frequently that just because one factor precedes or coexists with another that it does not automatically follow that one causes the other, I too am obviously guilty of falling into this trap.

Sometimes as a medical community we are criticized for insisting on controlled, randomized, blinded studies to prove efficacy of our treatments, tests and procedures. It can be an expensive, time consuming and sometimes frustratingly tedious process.  Still, without solid scientific controlled studies we will be at risk of taking what seems to make sense as factual.  Bleeding sick patients was accepted as dogma in centuries prior to use of the scientific method, and we need to beware believing everything we see.

What is Inflammation?

My latest in a series of my favorite Khan Academy health related videos is on inflammation.  I expected this video to be more scientific, teaching about the process commonly called the inflammatory cascade, a process where once something happens to start the inflammation process how the body responds with a series of chemical reactions leading to the cardinal signs of inflammation:  dolor(pain), calor(heat), rubor(redness) and tumor(swelling).  Actually the video is an interview with a physician about the long term vs. short term effects of inflammation and methods used to reduce inflammation.

Certainly don’t go out and start using all the drugs mentioned in the interview, but it is fun to watch and get you thinking.  Enjoy.

You may also like these previous posts:

Aspirin:  Should You Take One a Day?

Statin Side Effects:  Add Type 2 Diabetes

 

Taking a Break

I’m taking a break from new articles this week and suggest that readers consider looking at these two posts which may have slipped unread from the early DrPullen.com days.

Colon Cancer Screening: The Rest of the Story  Lots of people don’t get their colonoscopy done.  Don’t let inability or unwillingness to have this test keep you from inexpensive and effective alternative screening methods.

Brooke Douglas on Portion Control  A part of the eating plan for all of us is portion control.  Brooke Douglas, a registered dietician and regular contributor has advice most of us can use.

Have a great week.  DrP.

Support Tahoma Audubon’s Education and Conservation Goals


This is as far off topic as it gets, but I want as many readers and supporters as possible to contribute to the Tahoma Audubon Society by sponsoring my birdathon this year. What is a birdathon? Its where I spend 24 hours finding and identifying as many species of birds as I can. I’m leading a trip from Tacoma to Ocean Shores, WA and back starting about 3 PM on May 4th and ending exactly 24 hours after it starts. You can help by donating to TAS either by using my

 First Giving page

or by contacting me using the contact page on this site if you’d rather send a check directly.

I’ll post a trip report on this site and keep a running tally on the right side bar every few days.  Leave comments to encourage others if you contribute.  Send this on to any friends or fellow birders who may  be interested.  My goal is to raise $5000. or more by May 4th.  You can contribute a fixed amount, or pledge in a comment below to contribute an amount per species.  I hope to find 100 species of more.

Tahoma Audubon supports conservation in Pierce County, WA and beyond through education, political advocacy and hard work. TAS also supports teachers with curriculum materials and help for in class youth education.  TAS has several monthly field trips open to the public.  All-in-all TAS is an important part of keeping Pierce County and the Puget Sound region a lot healthier and ecofriendly.

Small donations from lots of readers will help meet this goal.  Donate now at  First Giving page.

DrP.

Overdiagnosis in Breast Cancer?

Overdiagnosis was not a term I ever heard in medical school, and I suspect it is one that few or you had heard of much more than a year or two ago.  Overdiagnosis is when a condition is diagnosed that is not causing any symptoms for a patient now, nor will it cause symptoms at a later time in their life.  I wrote about overdiagnosis earlier after reading the excellent book, “Overdiagnosed: Making People Sick in the Pursuit of Health” by H Gilbert Welch.

This book nicely discusses the issues of overdiagnosis in both chronic disease and in cancers.  The long-held assumption that all malignancies left untreated progress, spread and lead to death is simply not true.  We are learning that many types of cancer have unpredictable courses.  Prostate cancer is the most notorious of these, with good evidence showing that most prostate cancers are ones patients live with asymptomatically whether they know about them or not and die of something else without ever having symptoms of the prostate cancer. This is the primary issue behind the recent USPSTF “D” recommendation against routine PSA screening in asymptomatic men. There is strong evidence that some percentage of renal cell cancers, some types of breast cancer and thyroid cancers not infrequently regress or remain indolent and never lead to symptoms.

The recent evidence suggesting frequent overdiagnosis in breast cancer is very disturbing. An April 3 article in the Annals of Internal Medicine in a large retrospective review in Norway infers a 15-25% incidence of overdiagnosis in women found to have breast cancer on mammographic screening. They used every other year screening, and suggest that for every 2500 women screened 6-10 cases of overdiagnosis occurred, 20 women were diagnosed with breast cancer that was not overdiagnosis, and 1 death related to breast cancer was prevented.  We have strongly encouraged women to get annual mammograms for years. Personal anecdotal experience can make us even more confident that we are doing the right thing.  I have had many patients diagnosed with early breast cancer by mammogram over the last 20+ years, and until recently had not had any women over age 40 that I can recall diagnosed with advanced stage breast cancer who had been getting their annual mammograms.  It was very intuitive and tempting for me to believe that I was saving many lives and preventing much morbidity by aggressively pursuing early breast cancer diagnosis.  I know that I have put many women through emotionally stressful and uncomfortable additional testing, biopsies, and breast cancer treatment.  It is concerning to think that I may be subjecting some of these women to overdiagnosis and unnecessary treatment, but until we as a society actively address the issue of overdiagnosis and try to find ways to figure out which early cancers found on screening can be managed with active surveillance and which need curative treatment we are left with the inevitable overdiagnosis dilemma. This will  involve asking a cohort of women with various very early cancers to be observed for progression prior to intervention.  Whether this is going to be acceptable is not clear.  We need to do the same thing for men with early prostate cancer.  We are following lots of men with prostate cancer, but as far as I know not in a formal study that will give us help in knowing which cancers can be safely followed.  For now I’m doing nothing different except keeping my eyes wide open to further research and recommendations.

 

Much of what we do in medicine today is aimed at early diagnosis of asymptomatic disease, and overdiagnosis is a very valid concern any time we are screening for asymptomatic disease. The recent changes in criterion for hypertension, diabetes and hypercholesterolemia are leading us to the preventative treatment of many diseases that are of themselves asymptomatic.  The whole issue of overdiagnosis is going to be fascinating to follow over the next decade or two.

You may also enjoy:  PSA Controversy Continues

 

 

 

Understanding What Causes Heart Disease

In order to help readers understand what causes heart disease here is another in my Monday series of selected Khan Academy Health related videos will focus on coronary artery disease and heart attacks.  This video is quite helpful in laying out the basics of heart disease, and should answer most of the answers as to what causes heart disease. A few clarifying points may make it a bit more helpful.  First when they talk about an atherosclerotic plaque rupturing and leading to a clot that causes a heart attack they don’t mention that the mechanism of the clot’s initial formation is the aggregation of platelets at the site of the ruptured plaque.  That’s why we often recommend taking low dose aspirin to inhibit platelet aggregation, so that if a plaque ruptures platelets are less effective at aggregating at the site and causing complete coronary artery blockage.  In addition medications like the statins and possibly the ACE inhibitors or ARB medications probably function at least in part by stabilizing the lining cells of arteries and reducing the chances of plaque rupture.

One other comment is that the video implies that only if a large heart attack occurs is cardiac arrest likely.  Actually even small heart attacks, and likely even episodes of coronary ischemia not severe enough to cause actual death of cardiac tissue can lead to cardiac rhythm disturbances, a.k.a. cardiac arrhythmias that may cause cardiac arrest and sudden death.

The key to preventing coronary artery disease, heart attacks, heart failure and cardiac arrest is to lower your risk of developing atherosclerosis.  The primary risk factors are tobacco use, high blood pressure, diabetes, lipid abnormalities like high LDL cholesterol and low HDL cholesterol, obesity and sedentary lifestyle. In some cases other familial factors play a role, but most often a strong family history of heart disease is because of a hereditary tendency to one or more of these risk factors.

So what do you do? In order of importance in my opinion:

  • Don’t smoke.  If you do smoke quit now.
  • If you have high blood pressure be sure it is well controlled.
  • If you have diabetes do everything you can to control your blood sugars.
  • If you have high LDL cholesterol and other risk factors discuss use of a statin or other lipid lowering medications with your doctor.
  • Stay fit.  Exercise regularly, reduce your dietary animal fat intake, and lose weight if you are overweight or obese.
  • If you already have atherosclerotic vascular disease, i.e. if you have had a heart attack, stroke, or peripheral artery disease even more aggressive treatment of risk factors like high cholesterol, high blood pressure, obesity, and diabetes is important.  Ask your doctor about how to accomplish these things.
  • Ask your doctor about taking an aspirin daily.

Coping With Grief: Eat, Sleep and Carry On

I am far from an authority on coping with grief, but as a family physician of almost 30 years and having some personal experience with grief I feel that sharing some of my experience may be useful. I’ve had a fairly simplistic approach to grief for a long time, and am not completely sure how I came to this point, but it has worked for me and it seems to be well received and appreciated by patients. At least some of this came from the pastor who was a part of my residency program when my first wife died near the end of my third year. I seem to recall talking about this with Becky Sullivan MD, my residency director and mentor during my early years of practice in Puyallup. Still I think the crystallization of this triad of needs to be met during times of grief is something I came to understand and verbalize by talking to many patients over many years.
I believe a major key to getting through a time of great loss is to find a way to take care of our basic physical and emotional needs. I think of these as, “Eat, sleep and carry on.”

Eat: I too often see patients in acute grief with superimposed upper abdominal pain that I am certain is from gastric hyperacidity and not eating. Simply forcing yourself to eat can go a long way towards getting through a period of grief without complicating peptic ulcers or gastritis. I tell patients that they don’t have to be hungry, don’t have to feel like eating, and don’t even have to eat an extremely healthy diet. They just have to force themselves to chew and swallow a reasonable amount of food three times a day. Tradition in many communities, religions and cultures bears out the importance of eating. It is a nearly universal custom for family, friends and relatives to bring meals to the bereaved.

Sleep: Sleep is very difficult for many people in times of great stress or grief. In my opinion this is one of the most important times for physicians to prescribe sleep aides. It is tough to maintain your sanity and move through the rituals, responsibilities and duties expected when you are reasonably rested. In a sleep deprived state this is nearly impossible. Don’t be afraid to ask your physician for help if sleep is a problem after a major loss.

Carry On: This is my way of saying that forcing yourself to participate in at least some of your usual daily activities is very helpful in regaining some sense of normalcy. If you stay home all day, only see others who are also grieving, and don’t force yourself to carry on with your usual life activities it is too easy to become all-consumed by your grief. If you exercise normally continue to exercise. If you go to church continue to go to church. If you are in a service club, a book club, a bowling league, or other routine activity try to get back into that activity reasonably quickly. It can really help as a distraction and start to lead to a feeling that life can and must go on after the loss.

There is much more to managing grief, and I’m certainly no psychologist. Still, the advice to eat, sleep and carry is a good base on which to base your recovery.

Understanding What is Your Hemoglobin A1C

Hemoglobin A1C, often shortened to just A1C or called glycosylated hemoglobin is a key indicator of blood sugar control for diabetic patients. My experienced diabetic patients want to know what their hemoglobin A1C is about every 3 months usually, and it gives valuable information, generally telling us how their blood sugar control has been over the last month or so. New diabetics may take a while to really understand the hemoglobin A1C concept, and family members, friends or others may confuse hemoglobin A1C with either hemoglobin levels or static serum glucose levels. The Khan Academy has come to our help with this video, the second in my series of Monday morning educational videos from this great new resource. Understand hemoglobin A1C in just over 6 minutes:

Stay tuned on Monday mornings, or at your convenience to see my latest favorite online video educational resource for understanding your health. Subscribe to never miss a post, or follow “@doctorpullenon twitter or Facebook.

Another Sign I’m Getting Older. Now I have Floaters

No not a bodies floating in the Manhattan River, an annoying small moving black opacity in the visual field of my left eye. Floaters are deposits that are located in the vitreous humor of the eye. Normally the vitreous humor is colorless, and light passes through the eye to the retina allowing us to see what we are looking at. A floater blocks a tiny part of the visual field and casts a shadow on the retina or refracts light that passes through the eye. Typically floaters move about in the vitreous, i.e. float, hence their name. Technically floaters can be variably sized, but are generally fairly small. Most people who have floaters find that they come and go, move when they move their head or eyes, and are more annoying at first, and as we become used to them are less frustrating.

For the first few days my floater, a tiny black spot in the left eye visual field seemed like a piece of sand on my glasses, or something on my computer screen, but I suspected because it moved it was a floater. Like what many people describe my first inclination was to try to look directly at the opacity to figure out where it is located. This was a weird sensation because the floater would usually immediately disappear when I tried to look at it. Intellectually I understand that this is because with movement of the eye the floater itself moves, and because its location in the eye causing the shadow on my retina is not where it appears to be. Still the first few times I thought I was imagining the speck. Then I closed my right eye and it persisted, closed my left eye and it went away, and I knew I had yet one more sign of my age. Floaters can occur in young people, and can even be congenital, but are more common with aging.

Other people describe floaters as spots, thread or cobweb like shapes, or other descriptions that float slowly through their eyes. These are not an optical illusion, but are real phenomena. Most floaters are caused by gradual shrinking of the vitreous body as some of the molecules in the vitreous dry out and become solid. These degenerate further into fibrils that can be seen as floaters. This vitreous shrinkage that occurs with age can sometimes lead to pulling away of the retina, a.k.a. a retinal detachment. Shrinking of the vitreous can lead to flashing lights across the vision due to mechanical stimulation of the retina, and retinal detachment can cause either a large floater-like area, a type of scotoma, or a sudden appearance of numerous floater-like opacities as blood from the retina disperses in numerous droplets of blood in the vitreous. If you notice a sudden occurrence of multiple floaters you should have a dilated eye exam by an ophthalmologist right away as a retinal detachment is a potentially treatable cause of vision loss.

In general floaters are considered a nuisance, and are not treated. For severe cases treatment may be appropriate, either through a vitrectomy or by use of a YAD Laser. Neither is commonly performed due to the risks of the procedures and controversy over the efficacy treatment. For me I just smile, thank God I can still see well, and try not to let my floaters bother me too much.

Leave a comment below to tell us about your floaters, or any personal experiences you have with this phenomenon.

Primer on Medicare Information

Every year, mostly later in the year, I have several 64+ year-old patients asking me about Medicare. Do I accept Medicare? Can I tell them what plan is best? Should I get a supplement? What about the Medicare Advantage plans? These are not simple questions, and I really can’t try to address these in an office visit and have any time for much else. In addition I am not an expert on the latest and greatest of Medicare details nor do I have a way to understand any individual patient’s specific needs.
I recently learned about the Khan Academy as a resource for parents, teachers and students to watch brief videos on a tremendous variety of educational topics, and that they also have a variety of health care topics. I’m going to review some of these, and post some of their relevant videos here. Some of your questions about Medicare will probably be answered on this vignette on Medicare:

Stay tuned for more videos, as I hope to find more relevant ones for this blog, and will post them on Mondays for the next several weeks. I’ve made a category called Health Videos so if you want to see just these you can choose that category on the right sidebar of this blog. Better yet subscribe using the area on the right. Enjoy.