Saturday, December 21, 2013

Some Issues About Evaluating Blood Pressure

A new report by an expert "guidelines committee" has shifted blood pressure norms for people over 60 years of age up to 150/90 from the previously accepted level of 140/90.  This has huge implications for many individuals presently taking anti-hypertensive medications, many of which have decidedly negative side effects.

This blog is not meant to evaluate the validity of this conclusion but to educate individuals about possible errors in blood pressure measurement.

Blood pressure is most often measured by using an inflatable cuff wrapped around the upper arm, a manometer (either a column of mercury, or a clock-face dial with a needle) and a stethoscope with which the examiner listens for the appearance and disappearance of pulse sounds in the crease of the elbow.  The blood pressure can vary based on a number of factors that affect these elements. Techniques used to record blood pressure in a doctor's office are "indirect."  The only true,"direct" method of measuring the pressure in a blood vessel is to attach a measuring device to the blood vessel directly - a procedure normally performed only in emergency rooms and hospital settings.

There is room for variability and some differences when the indirect measure of blood pressure is used. For instance:

1. The cuff may not be appropriately sized for the circumference and length of the upper arm - cuffs that are to short, or do not comfortably fit around the arm are apt to give falsely high pressures.  The reverse is true of cuffs that are too loose or to large.  The cuff must also be properly applied to the arm so that the bladder inside the cuff covers the brachial artery (the large artery in the upper arm.)
2.  Blood pressures are determined by the appearance and disappearance of sounds the blood makes as it moves under the stethoscope for which the examiner listens.  Clearly the auditory acuity of the examiner means something here. The ability to hear the initial and final sound depends not just on the examiner's ears, but also on the rate at which the air is released from the inflated cuff.
3.  Blood pressure may vary with body position.  It may also differ from one arm to the other.

Given the variables involved in the indirect recording of blood pressures, using absolute numbers as guidelines is fraught with the potential for error.  A blood pressure recorded as 154/90 could easily be an inaccurate reading of a pressure which may actually be 148/86, or even 158/94.

It would be more helpful to provide a "range" of normal (or abnormal) rather than an absolute number, given the variables discussed above.  And remember, one blood pressure recording is never enough to make a diagnosis of hypertension - there should be at least three such recordings over a period of a few weeks before a diagnosis is confirmed.

Tuesday, December 17, 2013

Children with Down Syndrome - How Times Have Changed

Susannah Meadows's book review in the Dec. 17 NY Times Science Section (Raising Henry, by Rachel Adams) discusses how the attitude towards children with Down Syndrome (also known as Trisomy-21) has changed.  Ms. Adams, a professor of English and American studies at Columbia University declined the amniocentesis which would have made a pre-natal diagnosis.  In describing Henry, who is now six years old, she makes the following heartwarming comment about what is described as Henry's essence:  "I couldn't have ever known about his great sense of humor or the sound of his infectious laugh.  Or the smell of his hair.  The delight he gets from singing along with music or pouring bathwater from one cup to another."  Her son is "separate from the diagnosis," she writes.

Ms. Adams goes on to describe the "abysmal" bedside manner of her physicians - the OB-GYN resident who "sewed her up"then "sprints out of the room," the pediatric geneticist who used Henry as a "teaching prop," without a word to Ms. Adams, and her obstetrician who assured her that "I wanted to make sure I didn't miss anything so I showed your records to my colleagues, and everyone agreed there was nothing."  So many doctors remain poorly trained in "people skills."  Medical schools must begin to realize that their job is to graduate not just physician-scientists, but physician-healers - doctors adept not just in the science of medicine, but in the art of healing as well.

When I was a young pediatric resident, Down Syndrome was often termed "mongolism" because of the "Asian" appearance of these children.  My chief of pediatrics routinely advised all parents of such children to institutionalize them immediately lest they adversely affect the family dynamic.  His "advice" frequently sounded more like a requirement and was, to the best of my recollection, most often followed.

Statistically 50% of children with Down Syndrome have congenital heart deformities, often rather severe forms, unfortunately.  When I was a trainee in pediatric cardiology, our team routinely declined to offer cardiac corrective surgery to these children, feeling that such treatment was far too involved for patients with Down Syndrome and that their lack of co-operation during the post-operative recovery period would add greatly to the risk and preclude a satisfactory outcome.

Attitudes have clearly changed.  No one is routinely institutionalized.  Surgery is no longer denied, and outcomes are excellent.  It has been a lifetime of change for me, especially as a pediatric cardiologist.

But one must remember that not all children with Down Syndrome have Henry's essence.  Some are extremely difficult to manage and very delayed developmentally - but so are some children without Down Syndrome.  And, finally, one needs to remember that children with Down Syndrome will become adults with Down Syndrome - and that is another issue altogether.

Thursday, December 5, 2013

Should We Mess With Aging

Studies on aging are primarily concerned with controlling the process rather than coping with the process.  A recent article discussed the frequent features of the aging male - namely the development of the "pot belly," loss of muscle mass and a decrease in sexual desire.  These processes of growing older are mediated in large part by a fall in the level of testosterone.

Articles describing research in the field of aging refer to this change in testosterone level as a "decrease in the normal level of testosterone."  But it is not a decrease in the normal level of testosterone -  it, in fact, is a normal level of testosterone commensurate with the aging male.

Studies directed towards reversing the aging process by abnormally increasing a level of a hormone, be it testosterone, estrogen, or some other such agent, are concentrating on converting us from the normal aging process to an abnormal one.

Anti-aging research continues.  Why?  Are we truly interested in extending life expectancy to 150, or perhaps even further?   Is government expense for research to provide us with the proverbial "fountain of youth," - to control the aging process whereby we will live far longer, but at a great human and economic cost to society -  treasure well spent?

As Daniel Callahan (age 83), emeritus president of the Hastings Center, recently wrote in a NY Times Op-Ed article (Dec 1):  "We may properly hope that scientific advances help ensure……that young people manage to become old people.  We are not, however, obliged to help the old become indefinitely older.  Indeed, our duty may be just the reverse: to let death have its day."