BMI Tests For Pilots: Avoiding The Issue

The proposed addition of neck circumference and BMI testing to the airman’s medical exam is inaccurate, misguided and of limited usefulness. The impetus behind this screening is the recent spate of tired pilots making mistakes and even falling asleep while on duty. In one such incident it was later revealed that the captain had sleep apnea which was viewed as a probable cause for his falling asleep enroute (since sleep apnea is not contagious, the reason for the first officer also falling asleep at the same time was chalked up to fatigue). While this change to the medical exam affects all pilots, including those who fly privately, this piece will focus on air carrier pilots.

Aviation is under a constant media microscope and these incidents while statistically miniscule, nevertheless raise the suspicion of the public. Falling asleep at a job as hazardous as those that exist in aviation should not be tolerated, but using a questionable screening process should not be accepted in an attempt to create a solution to a condition that may or may not exist and most likely is not the primary cause of exhausted pilots. For the record, each year there are over 100,000 motor vehicle accidents that are attributed to drowsy driving. Despite the loss of 1,500 lives, so far no public safety department has mandated obesity or sleep apnea tests for motor vehicle drivers, even commercial operators.

Body Mass Index Accuracy

It has been proven that people with extremely high body fat percentages are susceptible to obstructive sleep apnea. It has also been proven that sleep apnea causes both hypersomnia and insomnia, impairs cognitive function and can lead to cardiac arrest in extreme cases. These facts are also not in question. What is troubling is the method being used to determine this risk factor in pilots, namely, the BMI rating.

BMI, or body mass index is a handy method for calculating a person’s mass to height ratio. As such, it is useful as a quick evaluation concerning obesity. The problem with BMI is that it is a very “dumb” equation; it does not know what it is measuring. A “smart” doctor, trainer, or clinician has to interpret the number and take into account other physiological factors (even the CDC states that BMI is not a diagnostic tool). Unfortunately, because BMI requires no specialized equipment or tactile measurements on the patient, it is widely used by people who have limited knowledge about the human body, obesity, bone density or muscle mass. This results in gross misinterpretations and misdiagnosis for people of various body types.

Another problem with BMI is that it leaves out critical factors such as age, gender, and body fat percentage. As people age, they naturally lose muscle mass unless steps are taken to preserve it (such as lifting weights). The loss of muscle mass, while detrimental, will show up as a reduction in BMI, leading the patient to think that they are getting healthier. Women on average have less muscle mass than men, resulting in more women being classified as healthy and more men as obese, even if the opposite is true. And most tellingly, if a person is 5’8” and 190lbs with 8% body fat, they will score the same BMI as someone who is 5’8”, 190lbs and 30% body fat (it is the same logic as saying that a Ford F-150 and a Ford Mustang will perform exactly the same since they have the same horsepower). One would think that scenarios such as these would be easily noticed and accounted for, however that does not appear to be the case in several well publicized instances.

In recent months, stories have come out where middle schools with good intentions unwittingly labeled some student athletes as “at risk” or obese based on a BMI calculation. The fact that nobody in charge of the program even understood how to deal with off-scale errors caused by a student having more muscle mass than their peers is distressing. Part of this rampant misinterpretation stems from our nation’s obsession with weight as the be-all-end-all indicator of a person’s health. Weight alone is a useless metric. It merely tells us how much of an effect gravity has on a given person. It does not tell us the distribution of body fat or muscle mass, which are the critical values that directly affect a person’s well-being. And as previously mentioned, simply possessing the stats of being 5’8” and 190 lbs only means that you are 5’8” tall and 190 lbs. Any other inferences must be determined by checking body composition.

As angry as the students and parents were at this mislabeling, imagine if your job relied on BMI numbers that may not have any basis in reality. It has been shown that it is very easy to make sweeping generalizations based on spurious data and then pass off any errors as anomalies. Will an airline ignore high BMI numbers in a visibly fit pilot, or will they tell them to atrophy away some muscle mass in order to lose weight? Alarms should be going off in the head of every pilot in America. If it can happen to children in school, it can and is about to happen to them as well.

Flight Fatigue

The cockpit of a modern jetliner can be a very sleepy place physiologically speaking. Noise fatigue from the slipstream roaring past the windows (a very effective white noise generator), reduced oxygen levels even with a pressurized cabin, and the inability to simply stand up and walk around are just some of the fatigue inducing factors present. Any one of these factors by themselves are hazardous enough to have volumes written about their attendant risks. Somehow, they are not even mentioned as a possible factor in pilot fatigue in this new screening process.

In fact it is entirely possible that it is an attempt to divert attention away from the fact that the new rest rules enacted by the Federal Aviation Administration have not fully accomplished their goal of eliminating pilot fatigue. This is only because airlines are not required to fully implement these rules until the end of 2013. Federal regulations now allow air carrier pilots a maximum of 9 hours of flight time and at least 10 hours of rest per each 24 hour period. To those who don’t fly for a living, a 9 hour workday does not sound that difficult and 10 hours of rest seems like it should be adequate. In reality flight time only accounts for loggable time in the aircraft (in airliners, the parking brake serves as the aviation equivalent of a time clock).

The new rules do a much better job of eliminating fatigue due to deadhead commuting and excessive duty times. Preflighting, checking weather, waiting for ground stops to expire, briefing, and all other tasks directly associated with preparing to fly an aircraft are limited to no more than 14 hours per day. Unfortunately, traveling to the airport, leaving the airport and checking into hotels all accounts for time that is not yet definable by the FAA.

Confusion abounds in the general public as to how a pilot halfway through a 3 hour flight can fall asleep. While that one flight is only three hours, it may be the second flight that day on the third day of a four day trip away from home. Anyone who works 9 to 14 hours is going to be tired. Anyone who works 9 to 14 hours going back and forth between time zones, sleeping in unfamiliar beds, unable to establish a consistent exercise regimen and not having access to healthy, agreeable foods is going to be even more tired. Now ask that person to stay alert in an environment that is almost custom built to induce sleep for four days in a row. This is the real reason why pilots are tired, make mistakes and fall asleep. When two pilots fall asleep and overfly their destination, or when critical mistakes are made due to fatigue induced cognitive impairment, the last thing that should be looked at is sleep apnea. Is sleep apnea a risk? Absolutely, but in the long list of causal factors it is not anywhere near the top.

The combination of desire to generate profit, maintain public confidence in aviation and ensure pilots are not forced into unhealthy patterns is a difficult river to navigate. The FAA has tried to close a massive loophole in their prior regulations via their current definition of Flight Duty Period. Airlines have historically exploited this oversight and were against changes to the Flight Duty Period limits (see page 112). Currently the issue is that duty time ends once the aircraft is parked, not when the pilot arrives at the hotel (we are assuming the pilot is in the middle of a multiple-day trip and cannot simply go home). It can easily take an hour to go from the cockpit to a hotel room, sometimes more. Assuming the pilot eats immediately, that leaves roughly 30 minutes before they are supposed to be sound asleep in order to take advantage of the “8 hour uninterrupted sleep opportunity”. In the morning, the reverse is in effect as it takes a similar amount of time to get to the airport and check in at the crew room. It is easy to see how the 8 hours of sleep can quickly erode to 6 or less. As a good friend who flies for a major air carrier said, “The new rest rules need to address the fact that we can’t go to sleep while making the first turnoff, nor can we wake up at V1.”

Instead of neck circumference and BMI tests,  there should be demands for better scheduling practices for all air carriers. Require that pilots get up and walk around the cabin for a couple minutes every hour (security rules be damned). Mandate that pilots take a few breaths from their O2 masks whenever they feel tired. Implore the FAA to close the final loophole in the definition of Flight Duty Period. Consolidate preflight tasks or delegate them to a dedicated ground crew much like military does with its crew chiefs. Install better soundproofing insulation in cockpits to reduce noise fatigue and hearing loss. Encourage airlines to create dedicated “pilot apartments” at their bases to eliminate travel time for the crews. Any one of these potential solutions solves multiple major issues facing pilot workplace health, which is the most effective way of mitigating the fatigue issue.

Conclusion

Should obesity screening be conducted? Considering that airline pilots must possess a 1st class medical certificate which can only be obtained after a battery of tests including an EKG, it seems odd that severely obese pilots are just walking around by the thousands. Many aircraft are tough to fit into even for an average sized person, so there’s yet another barrier to the truly obese sitting in the cockpit. But for the sake of argument, let’s say that there is a sizable population of obese pilots. There are far more accurate methods of determining levels of adipose tissue distribution than a distorted height to weight ratio. Aerospace Medical Examiners are certainly intelligent enough to use methods such as caliper skinfold or bioelectric impedance to make the necessary measurements. Then that physician can make recommendations on what the pilot can do to reduce their body fat percentage. Focusing on body fat, not weight, will have a far more effective result on the pilot’s overall health than zeroing in on one potential condition.

Flying aircraft is mentally and physically taxing. Pilots are still just mere mortals who have the same body the rest of us have. It requires food, exercise and sleep or it will not function optimally. To expect them to operate like machines is not realistic. Airlines need to accept this, the FAA has to continue to support this and pilots themselves have to live with this. Until it is determined that fixing the underlying causes is worth the cost, we will continue to see more pilots making fatigue induced errors and overflying destinations while fast asleep.

Suggested Further Reading

Center For Disease Control: “About BMI For Adults
Sept 13, 2011
 
FAA: “New Obstructive Sleep Apnea Policy” ; Fred Tilton MD
November, 2013
 
Mayo Clinic: “Sleep Apnea
July 24, 2011
 
FAA: “Fact Sheet – Pilot Flight Time, Rest and Fatigue
January 27, 2010
 
FAA: “Flightcrew Member Duty and Rest Requirements
December 21, 2011
 
The Sleep Foundation: “Sleep Studies
 
National Institutes Of Health: “Neck Circumference And Other Clinical Features In The Diagnosis Of Obstructive Sleep Apnea Syndrome” ; Robert J.O. Davies, Nabeel J. Ali and John R. Stradling
October 24, 1991
 
NHTSA: “Drowsy Driving And Automobile Crashes” ; Kingman P. Strohl MD, et al
 
International Journal Of Obesity: “Accuracy Of Body Mass Index In Diagnosing Obesity In The Adult General Population”; A. Romero-Corral, et al
February 19, 2008
 
FlightPhysical.com: “Summary Of Pilot Medical Standards
February 26, 2007
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Free Your Hands For Exercise

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I see a lot of people working out with their phones. They’re either kept in a pocket, held in a hand or left on a bench/mat/machine. These options are inconvenient and unsanitary. The people who have armband cases avoid this, but have to look backwards and down to see their phone, not to mention many times the touchscreen will not work due to the plastic protective cover.

Off and on when I had free time, I experimented with different types of wearable phone cases. The realization occurred that the only place on the upper body that doesn’t change size and is also easy to view is the wrist. Thus, I focused on making a simple, inexpensive wristcase that would allow people to keep their hands free.

The result was the SpeakEZ. As far as I can tell, it’s the world’s first phone case designed specifically for the wrist. The design allows for people of various sizes to wear their phone around their wrist and adjust the viewing angle. If you want the screen portrait versus landscape, simply turn the case segment to the angle you desire.

It’s not just for the gym either. I personally have worn mine while driving, food shopping, ballroom dancing, flying airplanes and riding bicycles. I’ve also used it to get video of concerts, ducks chasing me in the park and a guy flying his quadcopter at night. Other users have their own experiences. One lady says it keeps her from having to go running with her phone in her sports bra and another person says he never leaves his phone at restaurants anymore.

The SpeakEZ is assembled in the United States and by the second quarter of 2014, all of the parts will be made in the United States as well. I invite you to take a look at the site and browse the different types that are available. Right now, I am only able to offer SpeakEZ for the iPhone 3, 4 and 5. In the works is the Samsung Galaxy S4 and Droid Razr which are also slated for the second quarter of 2014.

 

Don’t Blame The Holidays

It’s that time of year. We’ve already passed Halloween and with Thanksgiving around the corner, more and more people are going to start blaming holidays for their eating habits (why we pick the last quarter of the year to keep track of holidays is a mystery to me…nobody ever said that Armistice Day added 3 inches to their waistline).

There are two ways around this issue. The first is to stick to whatever dietary plan you’re on come hell or highwater. The second is to eat whatever you want and not worry that an extra turkey leg is going to cause unchecked obesity.

In Option #1, you have to be a bit of a hardnose in order to make it work. You have your eating plan and you stick with it. Going to Aunt Tallulah’s house? I hope she isn’t going to be insulted when you decline the stuffing, cranberries and pie. You really should hope she doesn’t have a baseball bat in the house, because when you pull out your Tupperware container of grilled chicken breasts and avocado slices and say “This is my dinner, but thanks anyway”, she’s gonna be livid.

In Option#2, you eat as part of the celebration with family and friends. You don’t intentionally try overdo it, but there will probably be a photo of you passed out on the couch with your belt undone in a post-feast stupor. That’s not a big deal because you never tag yourself in pictures anyway. The next day, you don’t freak out and run for 2 hours on the treadmill to “burn it off” (that’s not how it works anyway). You just go back to your normal workout and eating patterns, psychologically unaffected by the holiday.

Which one is right and which is wrong?

Neither and neither.

The wonderful thing about being an American is that you can still do what you want provided it doesn’t cause harm to anyone else (real harm, not “OMG I feel bad because he’s in better shape than me but ate more than me” harm). So do whatever makes you feel better. Personally, I’d choose Option #2 because I like people and I like to eat. I also understand the relationship between the body and food so the prospect of taking in extra calories is not frightening in the least bit. Not to mention, Option #2 gives much lower odds of getting wacked by Aunt Tallulah’s baseball bat. But I could see myself using Option #1 if the house I was going to was ridiculously unhealthy…I’m talking hot lard on top of Twinkies unhealthy.

The bottom line is no matter which one you pick, you cannot transfer responsibility for your actions to an inanimate day of celebration. Eat or don’t eat, the choice is yours. Just make sure when you make that choice that you own it and the results of that action.

 

As for me, I’m going to get another serving.