Does Tdap Protect You From Whooping Cough?

Within the past few years an epidemic of whooping cough swept through and injured youngsters in California and Arizona. There were tragic childhood mortalities in the frail not yet vaccinated pediatric population. The researchers from the Center for Disease Control and National Institute of Health swooped in and concluded that adults, primarily grandparents, were transmitting the disease to their newly arrived and not yet immunized grandchildren. They reasoned that the adults’ immunity from their childhood vaccinations with DPT had worn off and they were unknowingly transmitting it to the youngsters after a mild adult upper respiratory tract infection with bronchitis.  We were told that in adults, Bordetella pertussis produced bronchitis indistinguishable from a viral bronchitis. This was just the type of illness health care leaders were telling physicians not to prescribe an antibiotic for in their international campaign for the prevention of antibiotic resistance developing.  Little did they know at first that in adults, the bronchitis is a mild illness but in children it is aggressive and is often lethal.  They were not originally aware that long after our adult mild bronchitis resolved we could still transmit the bordetella pertussis to our grandchildren.

Their solution was to re-immunize adults with a pertussis booster in combination with your next tetanus shot. The combination was called Tdap.  A national information campaign was undertaken to get primary care physicians to spread the word to their adult patients.  The question is does it really work? In a recently published study led by Dr. Nicola P. Klein of the Kaiser Permanente Vaccine Study Center in Northern California which appeared in the Journal Pediatrics, it seems that the vaccine is only effective for a short time in the very healthy and robust 11 and 12 year children.  Their study showed that Tdap protected young adolescents 69% of the time in the first year, 57% in the second year, 25% in the third year and only 9% in the fourth year.  The vaccine was given during an epidemic in California in whooping cough in the hopes of averting a greater infection rate.

 

The failure of the vaccine to provide long term benefits in adolescents and teenagers will lead to different immunization strategies. Tdap is already a milder form of a former vaccine, scaled down to prevent some of the rare side effects seen when it was administered.  A possible return to that previous vaccine or whole cell preparation may be needed. Another proposal calls for vaccinating pregnant women hoping that their maternal antibodies will pass to the fetus and provide long term protection.

The real question with no answer is what about the millions of adults who received Tdap with immune systems far less robust and protective than adolescents?  Are they immune and for how long?  No one knows because the research has not been done or published yet.  Still the CDC and the NIH and the American College of Physicians call for adult immunization with Tdap.  The Kaiser Permanente Study will surely establish the need for an adult efficacy investigation. Until then we will give the Tdap while we wait for answers. It does raise the question of whether our approach to adult bronchitis should include an antibiotic that treats Bordetella pertussis until a quick test is developed to distinguish it from run of the mill viral pneumonias.

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FDA Approves Coronary Artery Disease Screening Test

FDA - Steven Reznick, MDMedPage Today, the online medical journal of the University of Pennsylvania School of Medicine, announced that the FDA has ” cleared a blood test ” to screen for heart disease known as Lp-PLA2 or lipoprotein associated phospholipase A2. This test is an individual marker of vascular inflammation produced within atherosclerotic plaques. Its use was cleared for screening in all adults with no history of coronary artery disease.

In a National Institute of Health study, known as Reasons for Geographic and Racial Differences in Stroke, it was shown in a review of 4,598 people, aged 45 – 92, that individuals above the threshold level for Lp-PLA2 were more than twice as likely as others to have an event, heart attack or stroke, 7% versus 3.3 %. The study was particularly helpful when looking at black women as a group. An Lp-PLA2 level > 225nmol/min/mL is considered elevated.

This test has been available to patients in our practice through the Cleveland Heart Labs screening panel. It plus the myeloperoxidase level, CRP and other markers have been felt by the Cleveland Clinic cardiology division to have predictive value. These tests are currently available but in many cases require private pay because Medicare and private insurers do not yet cover them all.

Drinking Coffee, Lower Mortality

Over the years, the consumption of coffee and its relationship to your health has been controversial.  In my medical school, internship, and training years in the late 1970‘s, it was thought that consuming more than five caffeinated beverages per day was associated with an increased risk of pancreatic cancer. That relationship has since been disproved.

The May 17th issue of the New England Journal of Medicine published a study on coffee drinking that will certainly make coffee drinkers more comfortable with a consuming a “cup of Joe.” They looked at a National Institute of Health – AARP study that began 1995 and includes almost 230,000 men and 173,000 women. They found that coffee drinking was associated with many negative behaviors including cigarette smoking, less exercise, eating more red meat, and eating less fresh fruits and vegetables.  Upon initially looking at the data, coffee drinking was associated with an increased mortality. However, when researches removed the negative behaviors from the data, and looked at the people who drank coffee but didn’t smoke and exercised; they found a significant drop in the mortality of coffee drinkers. Over 13 years, men who drank 4-5 cups of coffee per day had a risk reduction of 12% while women had a risk reduction of 16%.

The risk reduction was considered “modest” by Neal Freedman, PhD of the National Cancer Institute.  Lona Sandon, RD (registered dietitian) of the UT Southwestern Medical Center in Dallas said, “Based on this study alone I would not tell people to start drinking more coffee to lower their risk of death.”   She felt individuals should “stop smoking, be more physically active, and eat fruits, veggies, whole grains and healthy fats…. A little coffee doesn’t appear to hurt.”  Cheryl Williams, RD, of Emory Heart and Vascular Center in Atlanta commented that “if you are not a coffee drinker, this study is not a good enough reason to start.”

The study seemed to show that with consumption of 4-5 cups of coffee per day your risk of death due to cardiovascular disease, respiratory disease, injuries and accidents, diabetes and infections decreased. Coffee consumption did not appear to protect against cancer-related deaths. The design of the study does not allow us the luxury of saying drinking coffee is the “cause” of an “effect” of lowered overall mortality, but does certainly hint at it.

What is clear is that coffee drinking does not appear to have an adverse effect on already healthy lifestyles, but will not protect an individual from the detrimental effects of smoking, poor dietary choices and inactivity.