June 2002 - American Bonanza Society

HypertensionBY JOHN D. HASTINGS. M.D.Before revision of the FAA medical standardsin 1996, a pilot could obtain a third classairman medical certificate with a blood pressureup to 170 over 100 millimeters of mercury(mmHg). Though no new blood pressure limitswere established, the unofficial value, abovewhich the FAA becomes concerned, is 155 over95. Many physicians in practice will treat bloodpressure if it rises above 140 over 90. One of themajor dangers of untreated hypertension isstroke.Untreated hypertension increases the risk ofstroke by three to four times above that ofpersons without hypertension. It is estimated thatfor a 7.5 mmHg lowering of the diastolic bloodpressure (the bottom number) would reduce therisk of stroke by 46 percent, and a 5 to 6 mmHglowering can reduce stroke ri sk by 35-40percent. Since 49.3 percent of strokes are associatedwith hypertension, more strokes could beprevented if hypertension were controlled thanby any other modifiable risk factor.Even mild hypertension can increase therisk of stroke by 1.5 times. In one study, 75percent of strokes occurred in individuals withsystolic (top number) of less than 155 and adiastolic value less than 95. This suggests thatlowering blood pressure can reduce stroke risk inpersons with and without hypertension.From 1973 to 1992, there was a continualdecline in the incidence of stroke, probablylargely due to the treatment of hypertension. In1973, only 29 percent of people knew that hypertensionwas a major cause of stroke, whereas in1992, 90 percent of people knew it. There hasbeen no further decrease in the incidence ofstroke. Are we getting complacent? Perhaps so.So what is the point of all this? 1 simplywant to point out that elevated blood pressureshould be taken seriously. Whether through diet,exercise, salt restriction and medication whennecessary, blood pressure must be controlled toprevent stroke and other compli cations ofhypertension.See you next month.ABS member John Hastings, M. D.. holds board certification inneurology and aerospace medicine. He has been on aviationmedical examiner since 1976 and serves as a senior AM£. Heholds a commercial pilof license with mulfiengine and instrumentratings. He is chairman of the EAA Aeromedical AdvisoryCouncil, post president at the Civil Aviation Medical Associationand on the council of the Aerospace Medical Association. He isan ABS Director and heads the Society's AeromedicalCommittee.QUESTIONS OF THE MONTHQ: I had an episode at 8,500 feet where [could not communicate my thoughts, and my lefthand was clumsy. [ was able to land, and everythingcleared in several hours. [ had an MRI brainscan, and my neurologist tells me [ had a smallstroke deep in the right side of my brain (J am lefthanded). Does this mean no more flying andshould I tum my license in to the FAA? Do [have to make some type of formal report?A: It seems clear that you had a mini-stroke.This will ground you now, but not necessarilyforever, You should stop flying now, but there isno rule requiring you to tum in your pilot licenseor your medical certificate. You do have to groundyourself until the matter is settled with the FAA.You did not mention whether or not youhave a history of hypertension, commonly presentwith small strokes. The FAA will considercertification in two years following stroke,During that time, they like to see attention tomodifiable risk factors such as smoking, weightcontrol, diet, exercise, treatment of cholesteroland other lipids if needed, and good control ofhypertension if present. Others would includediabetes, history of heart disease, etc. With goodrecovery, you would be able to regain certificationaner this interval of observation. You didnot mention your age or the presence or absenceof other risk factorsYou do not have to report anything now.You wou ld have to gather all records includingMR1 reports, carotid ultrasound studies, echocardiograms,stress tests, laboratory studies includinglipids, and notes from your primary carephysician and your neurologist when youattempt to regain certification after the two-yearwaiting period. I would put this together 90 daysABS June 2002