If you’ve ever worked a night shift (or come in early for a day shift), you know that there is an increased incidence of cardiovascular catastrophes such as stroke and MI in the morning hours (approximately 6 AM to noon). This phenomenon is attributed to normal diurnal changes in human vascular endothelium and possibly platelet function, coupled with a surge in blood pressure that is a response of mammalian cardiovascular systems to typical circadian influences. Some of these changes apparently relate to baroreflex activity and our adrenergic vascular responses, and possibly to periods of inactivity followed by typical awakening activities such as mobilization.
What physicians are less likely to appreciate, however, is that this same increased risk of cardiovascular disease is conferred upon EPs who have forced variations in their normal mammalian circadian patterns, such as the imposition of rotating shift work. In fact, the shift work schedule confers an approximate 40% increased risk of developing cardiovascular disease. That is a risk nearly the equivalent of smoking one pack of cigarettes a day. Since cardiovascular disease is a leading cause of death for adults in all age groups worldwide, this statistic should strike fear in the minds – indeed, the hearts – of emergency personnel everywhere.
Other research has indicated that fluctuations in blood pressure throughout the day can increase the potential for cardiovascular disease, as well as sustained hypertension, not to mention unremitting stress. All of these can occur during shifts in a high volume ED. More recently, evidence has begun to accumulate that rotating shift work with its associated sleep disorders can alter our endocrine systems in such a way that lipid profiles, insulin resistance, estrogen and testosterone levels are shifted so as to increase the risk for development of diabetes, hypertension, hyperlipidemias, and incidentally, certain hormonally-dependent tumors. Truncal obesity is a risk factor for development of Metabolic Syndrome and Type II diabetes, both of which increase cardiovascular risk. Anxiety, stress and depression are aggravated by circadian disruption, and unfortunately depression is another independent risk factor for the development of cardiovascular disease.
And it bears mentioning, though is hardly news, that smoking, poor dietary and exercise habits will contribute to the development or the exacerbation of cardiovascular disease to which we may already be predisposed. Alcohol and drug abuse can certainly also be contributing factors.
So, what’s an EP to do? Shift work is rarely avoidable in our profession. Some very excellent information is available on rational management of shift work in the Policy Research and Education Paper that accompanies ACEP’s recently revised Shift Work and Circadian Rhythms Policy (www.acep.org). Recommendations include rational scheduling using either dedicated night shift workers (who are appropriately compensated for the additional toll that may be taken on their bodies), or rotating but infrequent night shifts on a clockwise rotation (which minimizes risk of circadian disruption), and scheduling eight-hour shifts. Practical sleep hygiene measures should be applied by shift workers, such as establishing a quiet, dark, cool place to sleep without the encroachment of beepers, phones, doorbells, etc. These should be coupled with continuing education of family, friends and neighbors about the necessity of quality day sleep for those who work even occasional nights. Anchor sleep periods should be developed by dedicated shift workers and rigorously observed, even on days off, in order to be maximally effective.
Departmental and hospital administrators should understand and excuse those who work night shifts from daytime meetings even if alternative arrangements must be made for CME and administrative updates. Adaptive dietary habits such as avoidance of alcohol and caffeine, and the consumption of a carbohydrate rich meal before sleeping, and intake of high protein on arising should be developed. Other manipulations such as exposure to bright lights on awakening, exercise, hydration, and possibly the use of melatonin when necessary to promote sleep may be applied, but pharmacologic manipulation should be avoided because of the increased addictive potential of some of these interventions when chronic use is prompted by work requirements.
Obviously, smoking cessation should be the cornerstone of any cardiovascular risk reduction strategy. There is evidence that this can be effective at any time in a smoker’s life. In some EDs it seems that a smoke break may be the only “legitimate” excuse for taking time out of a stressful shift, and this may be more of a hazard even for ED nurses than EPs. Establishing a quiet “break room” where napping or meditation is actually possible should be considered as a health preserving alternative to smoke breaks, and although it is not an option for nurses in most institutions to “nap” on the job, there is no reason that such an accommodation should not be available to nurses as an alternative to a “time out on the ambulance ramp.”
Other columns in EPM have suggested healthy alternatives to the typical night shift snack of cold pizza and deep fried doughnuts. Our police partners (who apparently get free handouts from certain purveyors of these products and freely share them with us at night) are at least slightly to blame for the centripetal weight gain often experienced by night shift workers. (I don’t know how to discourage this behavior without being impolite, but personally I became highly selective about the type of doughnut I would indulge in, and it was, thankfully, rarely available anymore late at night.) Although caffeine is almost a necessity on night shift, all forms should be avoided at least four hours prior to anticipated sleep. A high protein snack or drink might be substituted, the arousing effects of which may be dissipated more rapidly than caffeine when bedtime arrives.
I am a big believer in dietary supplements and would recommend both a quality multivitamin, extra Vitamin D, Calcium, Magnesium, Coenzyme Q-10, Resveratrol, EPA and DHA supplementation for all adults, but especially for those of us who pursue shift work.
We don’t yet have precise data about the overall risk or potential for increased mortality among emergency personnel due to cardiovascular or other effects of shift work or work in a highly stressful specialty. We are still a young specialty and only a few studies have even broached the subject or reached maturity. More research undoubtedly should be pursued. But the best prevention of any catastrophe is always avoidance. It would behoove all groups to consider seeking dedicated night shift staff, providing a substantial shift differential, and teaching all emergency personnel starting at the very beginning of training, that our potential increased risk of developing several lethal diseases, including cardiovascular, mandates redoubling our efforts to live as healthy a lifestyle otherwise as we possibly can.
Dr. Andrew is a trial preparation consultant and litigation stress counselor. Find more on risk management, litigation and wellness at mdmentor.com