September 2, 2010
- Full Report (pdf)
- Part 1: Resident Physicians Work Excessive Hours
- Part 2: Evidence of Harm to Resident Physicians
- Part 3: Existing Hours Limitations for Resident Physicians and Non-Resident Physicians
- Part 4: The Same Rules to Protect Resident Physicians and Subspecialty Resident Physicians Will Also Protect Patients
- Part 5: Arguments Against Reducing Work Hours
- Part 6: OSHA Has Jurisdiction Over Limiting Resident Physician Work Hours
- Part 7: Requests
PART 2: EVIDENCE OF HARM TO RESIDENT PHYSICIANS
In our review of harms to resident physicians, we limited ourselves to studies that included resident physicians (and not physicians in general) as the study population, and only studies that used work hours or hours of sleep as the predictor variable, treating specific effects on health as the outcome variables. Application of these selection criteria resulted in elimination of some of the literature on resident physician harm; however, for four specific health hazards — motor vehicle crashes, mood alterations and depression, obstetric complications, and percutaneous injuries (e.g. needle sticks) — studies did match our selection criteria. For each hazard, we present background information, describe relevant studies, and summarize key findings.
A. Motor Vehicle Crashes
The news is peppered with stories of resident physician involvement in car crashes, or near crashes, while driving from the hospital. In January 1999, a resident physician named Valentin Barbulescu had just finished a long shift in the cardiac care unit and was driving off to take an important certification exam. Dr. Barbulescu was killed in a one-car crash in rural Pennsylvania, an accident his colleagues reported was due in part to fatigue.
An emergency medicine resident physician wrote a letter in 1998 to the editor of the Annals of Emergency Medicine, describing how he woke up at the wheel just in time to stand on the brakes and skid 73 feet before hitting the back of a 10-ton truck going 5 miles per hour. He was on his way home from the second of two 12-hour night shifts. The resident physician suffered 10 fractures and the failure of his new marriage as a result of the accident.
In 1990, a New York City resident physician fell asleep at the wheel of his car after a sleepless 36-hour shift at New York City Hospital, and awoke to find his car stopped on FDR Drive, with traffic driving around him. A resident physician from the surgery program at Johns Hopkins, Dr. Moriarity, relates:
I think outside the hospital, you know, most residents fall asleep at the wheel driving home from work. Almost every resident I know in that program [surgery] has fallen asleep at the wheel driving home from work. And many of them have been in car accidents. Inside the hospital, they fall asleep at the operating table…
An informal survey published in JAMA in 1988 found that six out of seven surgical resident physicians had fallen asleep at the wheel while driving to and from work, and three had been involved in car accidents. One doctor commented, “Falling asleep at the wheel post-call is virtually universal. I have not found anyone who has not had this problem.”
In the published scientific literature, there is strong evidence that resident physician work hours are associated with an increased risk of motor vehicle crashes, especially after working more than 24 continuous hours. In a New England Journal of Medicine study, published in 2005, the Harvard Work Hours, Health, and Safety Group collected monthly data from 2,737 interns across the U.S. to investigate the relationship between hours worked, motor vehicle crashes, near-misses, and incidents involving involuntary sleeping. In a within-subjects analysis, the investigators found that the risk of a motor vehicle crash was increased significantly following a work shift of 24 hours or greater, compared with the risk of a crash following non-extended shifts (OR 2.3; 95% CI, 1.6-3.3). They also found a significantly increased risk of a near-miss accident (OR 5.9; 95% CI, 5.4-6.3) after a shift lasting more than 24 hours. Moreover, a dose-response relationship was identified in a second prospective analysis using the same dataset, providing strong evidence of a causal connection between extended shifts and the risk of motor vehicle crashes. For each additional 24-hour shift worked in a month, the probability of any motor vehicle crash increased by 9%, and the probability of a post-extended shift crash increased by 16%, in an additive fashion. Thus, for resident physicians on a “q3” (every third night) schedule, a schedule in which resident physicians work 10 extended duration (> 24-hour) shifts per month (a common schedule, and one that is sanctioned by the ACGME under both the existing 2003 ACGME regulations, and under the proposed 2011 ACGME regulations), the risk of a crash after an extended duration work shift was increased 160% (i.e., 16% per shift x 10 shifts).
Researchers from Johns Hopkins Hospital examined how sleep deprivation affects driving in pediatric resident physicians, and used pediatric faculty as the control group. Questionnaires were administered to 70 pediatric resident physicians who were on call every fourth night, and to 85 faculty members who were rarely disturbed at night. The response rate was 87%. Resident physicians averaged 2.7 (SD 0.9) hours of sleep while on-call vs. 7.2 (SD 0.8) hours of sleep when not on-call (p < 0.001). Faculty slept 6.5 +/- 0.8 hours at night. Twelve-point-five percent of pediatric faculty had fallen asleep while at the wheel at a stop light over the preceding three years, compared to 44% of resident physicians (p < 0.001). Forty-nine percent of resident physicians reported falling asleep at the wheel (not necessarily at a stop light), and 90% of these events occurred after the resident physicians had worked an extended duration (> 24-hour) shift. The authors reported, “One [resident physician] wrote that she routinely used her emergency brakes when stopped at a light because of her sleepiness post-call.” The report concluded, “We have demonstrated that [resident physicians] have an increased incidence of falling asleep at the wheel when driving home post-call, and this probably has resulted in increased … motor vehicle accidents.”
Yet more evidence comes from an abstract published in Anesthesiology, in which investigators surveyed 74 anesthesiology resident physicians at the Hospital of the University of Pennsylvania. Resident physicians were asked to report traffic accidents, near-miss accidents, or traffic violations that occurred during their residency and which they attributed to fatigue. Information on traffic conditions, time of day, call frequency, and hours of sleep on-call prior to the crash was obtained. Seventy-eight percent (58) of the resident physicians responded. Crashes during residency were reported by 17% of the resident physicians, with all crashes occurring between 8 a.m. and 9 a.m. (driving home post-call) in “moderate” to “no” traffic. “Near misses” or narrowly avoided crashes were reported by 72% of resident physicians, with one-third of this group having had five or more. Most resident physicians (85%) indicated that they were specifically concerned for their safety because of fatigue while driving home post-call.
Wendt has referred to chronically sleep-deprived resident physicians as “misguided missiles.” This is not an exaggeration; resident physicians are truly impaired drivers. A prospective two-session within-subject study of 34 volunteer pediatric resident physicians (out of 115, or 30%) in JAMA compared sleepy resident physicians to intoxicated resident physicians. Investigators examined the neurobehavioral performance of resident physicians at the end of a heavy-call month and compared it with the neurobehavioral performance of resident physicians after a light-call month. The light-call condition was equivalent to a clinic month with few overnight calls, if any. The heavy-call condition was similar to a traditional schedule of call every fourth or fifth night. The study found a decrement in post-call performance of the heavy-call group similar to that of a resident physician on a light-call month with a blood alcohol concentration of .04-.05 g. %, in the areas of sustained attention, vigilance, and simulated driving tasks. Reaction times were 7% slower (p < .001), commission of errors was 40% higher (p < .001), and speed variability was 71% greater (p < .001) in heavy-call resident physicians compared to light-call resident physicians.
Indeed, multiple studies establish that motor vehicle crashes are an occupational hazard for a significantly high number of resident physicians under their current working conditions. It is common sense that excessive work schedules contribute to resident physician fatigue and increase the risk of serious motor vehicle crashes. Moreover, resident physicians unfit to drive due to fatigue and sleep deprivation represent a threat to other drivers on the road. In 1998, a first year Anesthesia resident physician at Rush Presbyterian Medical Center in Chicago was driving home after an extended-duration work shift of 36 hours and rear-ended a car driven by Heather Brewster, a young graduate student whose severe head injuries changed her life forever. The Brewster family sued Rush for scheduling the young resident physician to work such dangerously long shifts, but the hospital argued that it was the intern’s decision to drive home, so the liability belonged solely to her. The state’s highest court agreed. It is clear that OSHA would be acting in the interest of both resident physician health and public health by reducing work hours for resident physicians.
B. Mental Health
Negative Effects of Work Hours on Mood and Affect
Mood is defined as the prevailing subjective emotional state (such as happy, sad, euphoric, irritable, or agitated) of a subject, and affect is defined as how the subject’s mood is expressed. Depressed mood in particular is characterized by general hopelessness, passivity, lifelessness, dysphoria, demoralization, and pessimism. Subjects can be irritable, emotionally unstable, and argumentative; some can be agitated and anxious, while others are quietly apathetic and vegetative.
In 1973, a case study of 14 interns at Columbia Presbyterian Hospital was published to examine work hour effects on mood. Although the hours worked then were longer than the hours worked now (resident physicians were on-call every other night, and often worked 60-hour shifts), the study is still relevant today because it shows how mood is negatively affected by lack of sleep. The following are comments taken directly from study subjects, all of whom experienced mood alterations:
Difficulty Concentrating. “When I’m tired, even though my mind is active, I can’t concentrate. I can’t put things together in my mind so I don’t even try. If a patient is really sick, I can pull myself together but I can’t write down what I’ve done in the chart. What I write is a reflection of a fragmented thought process…. It gets me scared when this happens because it means that I am losing control of my ability to think.”
Depressed Mood. “My home life suffers and I miss my wife greatly. I feel ashamed that I get tired and can’t live up to the tradition of the ‘iron men.’”
Irritability. “As I lose sleep, I get more explosive and more irritable. I snap at nurses and make them cry. I pick on the nursing staff rather than my wife or my patients. I’m ashamed of it in a way.”
“If you’re on two nights in a row, you want to do as little as possible. You give bad care. I am irritated all the time then … I give bad care to my patients, unfortunately. When I’m tired I don’t give a Goddamn.”
Inappropriate Affect (“Black” Humor). “I laugh at things that aren’t really funny. I’m giggly when I’m tired. For instance last night a patient came in comatose. Another intern asked the patient: ‘Do you have any parakeets at home?’ I found this enormously funny and I laughed and laughed … Things don’t seem so funny to me when I am rested. Another example of my sense of humor when I am fatigued would be: An intern gets a patient with congestive heart failure and pulmonary edema. He makes a wise comment like, ‘Give her some vitamins and send her home.’ That makes me crack up. I would not find such a remark funny when I am rested.”
Memory Deficit. “I would forget what I just said so my next sentence would make no sense. I also stop sentences midway a lot because I forgot what I wanted to say.”
Other studies confirm these mood effects using objective measures. At Columbia University, investigators used the Nowlis and Green Mood Adjective Check List (MACL) to compare 14 interns when rested and fatigued. The MACL consisted of 33 adjectives describing 11 mood factors: aggression, anxiety, surgency (feeling carefree, lively, talkative), elation, concentration, fatigue, social affection, sadness, skepticism, egotism, and vigor. In the 32 hours before testing, rested interns slept a mean of 7.0 hours and fatigued interns slept a mean of 1.8 hours (p < 0.001). Tired resident physicians reported worse scores than rested resident physicians, with tired resident physicians having statistically lower scores in positive mood factors (surgency, vigor, elation, egotism, and social affection) and significantly higher scores in negative mood factors (fatigue and sadness).
Another study randomly assigned 30 first-year internal medicine resident physicians to sleep-deprived (n = 16) and non-sleep-deprived (n = 14) groups, and followed them from the fifth to the ninth month of their internship year at the Medical College of Virginia Hospitals. The two groups had a similar age, sex ratio, and racial composition. Resident physicians in both groups were tested with the Multiple Affect Adjective Check List (MAACL) from 2 p.m. to 3 p.m. after being on-call or after having been off work. Sleep-deprived resident physicians (mean 2.7 hours sleep) reported greater mood disturbance than non-sleep-deprived resident physicians (mean 7.9 hours of sleep) in the different categories of the MAACL (p < 0.05).
Researchers at Case Western Reserve University compared 34 pediatric resident physicians before and after a night of call with 27 resident physicians who were not on-call either day. The different groups were tested using the Profile of Mood State scale (POMS), a 65-item adjective-rating measure that assesses mood state on a five-point scale. A total score is provided, as well as subscales for tension-anxiety, depression-dejection, anger-hostility, vigor-activity, fatigue-inertia, and confusion-bewilderment (higher score = worse mood state). The on-call group of resident physicians showed increased total negative mood state scores (pre-call: 54; post-call: 74), while the group not scheduled to work extended duration (> 24-hour) work shifts on any of the days demonstrated improving total mood scores (Day 1: 60; Day 2: 49). The scores for all six subscales of the POMS also demonstrated increased negative mood for the on-call group post-call, while the off-call group demonstrated improved mood on the second day.
Studies thus consistently show that resident physicians experience negative, unhealthy alterations in mood as a result of their long work shifts. These effects last longer than just the post-call day. In one study that demonstrated this, 52 volunteer medicine resident physicians (out of a possible 148, or 35%) were followed each of three days post call (on a 1-in-4 schedule) and were assessed on mood (POMS) and sleepiness scales (ESS). Sixty percent (31) of these volunteers returned usable data. The results showed that actigraphy recorded total sleep time (TST) on-call was 3.8 +/- 2.4 hours. Recovery sleep after call was inadequate to stabilize mood. In fact, the effects of call lasted well into the off-call days, with tension, depression, and anxiety leveling on the first post-call day, and vigor, fatigue, and confusion leveling after the second post-call day. Put another way, the investigators said, “Call affects [resident physicians’] mood[s] for much of the time when off call and potentially their personal and professional interactions during this period as well”.
Distinct from depressed mood is depression, a clinical term requiring that at least five of nine defined criteria are met for a period of at least two weeks. One of the five signs must include either depressed mood or anhedonia (loss of interest/pleasure in life), and the other four can include appetite disturbance with weight change, sleep disturbance, psychomotor disturbance, fatigue or loss of energy, feelings of worthlessness or guilt, diminished ability to concentrate, and recurrent thoughts of death/suicidal ideation. High rates of depressed mood place resident physicians in a higher risk group for developing clinical depression. Indeed, as many as 30% of resident physicians experience depression at one time during their residencies. Female physicians have been shown to be especially vulnerable.
In research utilizing the Center for Epidemiological Studies-Depression (CES-D) scale, a predictor of depression, investigators surveyed 68 medical house officers at Rhode Island Hospital.  They administered the test on a monthly basis for a year, with a response rate of 83%. Twenty-one percent of respondents reported “depressed” scores, defined as a CES-D score equal to or greater than 16 (on a scale of 0 to 60). When classified by year, 29% of first-year resident physicians, 22% of second-year resident physicians, and 10% of third-year resident physicians reported depressed scores (p < 0.0001). (Resident physician work schedules typically improve as residency progresses.) When responses were examined by rotation (the specialty in which a resident physician is currently working), depressed responses were most frequently received during those rotations that routinely required over 80 hours of work per week. Twenty-five percent of resident physicians reported depressed responses while on ward rotations, and 32% while on intensive care unit rotations, both of which can require 100 hours of work per week. The author concluded, “The increased frequency of depressive symptoms on ward and intensive care rotations may be, in large part, caused by long working hours and sleep deprivation.”
In a study at two hospitals in St. Louis, investigators interviewed 53 interns at the end of their first year of training.  Based on established criteria for clinical depression, 16 (30%) had an episode of depression during their internship, of which 13 were definite depressions and 3 were probable depressions. The depressed and non-depressed groups were very similar in terms of age, sex, marital status, and type of internship. Medical, social, and childhood histories were not significantly different either. Eleven of the 16 interns became depressed within the first few months of their training. Four of the 16 had suicidal ideation, three had a suicidal plan, and six experienced marital problems for the first time. One subject who had made a suicidal plan thought of five or six ways to kill himself so that his wife could collect insurance. Six depressed interns had feelings of hopelessness, two had fear of losing their minds, and three called their spouses while on night call, crying and saying they couldn’t go on. Of the 11 whose depression began in the first two months, seven were working more than 100 hours per week. Of the five who became depressed later in their internship, three were working more than 100 hours per week at the time of the onset of their depression.
A larger study showed similar results. A volunteer cohort of 740 (58% of 1,271 invited), interns was assessed for depressive symptoms before commencing residency, over the course of the first year, using the nine-item Patient Health Questionnaire (PHQ-9) depression score. On this test, scores can range anywhere from 0 to 27, with higher numbers indicating more severe depression. The percentage of participants who met criteria for depression increased from 3.9% before internship to 25.7% during internship (p < 0.001). (The raw score increased from 2.4 prior to internship to a mean of 6.4 during internship.) Most of the subjects who met criteria were moderately depressed. Factors associated with depression during internship were perceived medical errors, stressful life events, and increased work hours (p < 0.001).
Moreover, depression is problematic not only for resident physicians themselves, but for their patients. In a three-center study of the relationship between medical error and depression, Fahrenkopf et al. found that 74% of all resident physicians met criteria for occupational burnout (Maslach Burnout Inventory) and 20% of all resident physicians scored positive for depression using a validated screening instrument (Harvard Department of Psychiatry Screening Tool). Virtually none of the resident physicians had been diagnosed with depression prior to beginning residency. Of great concern is that doctor depression has a profound impact on the care of patients: depressed resident physicians made six times as many medication errors in the care of their patients than did their non-depressed colleagues.
In sum, while it is certainly possible that the difficult nature of medical work in residency contributes to the development of depression, it is supported by evidence that excessive work hours are also a major factor. Fatigue and sleep deprivation caused by excessive work hours contribute to depressed moods in resident physicians, placing them in a high-risk group for developing clinical depression, and in turn increasing their risk for suicidal ideation and suicide. Even more alarming, studies suggest that the development of major depression is linked to a higher risk of future depressive episodes. We may thus be predisposing resident physicians to mental illness. Experts have agreed, “This combination of stress and fatigue may lead to severe psychologic repercussions, which may first appear as disappointment, loss of idealism, and isolation, and then progress to feelings of helplessness, impaired performance, and outright depression.” The authors of another study concluded, “In view of the special vulnerability of medical trainees to occupational stress, all efforts are warranted to reduce sleep deprivation in the medical profession.” It is reasonable to expect that reducing work schedules to allow for more sleep should reduce both the incidence of depressed mood and the likelihood of developing depression.
C. Obstetric Complications
A growing number of women are entering the medical profession, and almost 50% of married, female resident physicians will become pregnant during their residency. Moderate increases in work schedule more than 40 hours are not consistently associated with adverse pregnancy outcomes. However, excessive levels of work are associated with obstetric complications.
In the best-designed investigation, Klebanoff et al. sent questionnaires to 5,096 female physicians who had graduated from medical school in 1985 and to a random sample of 5,000 of the 12,306 male physicians who graduated the same year. Eighty-seven percent (4,412) of the female resident physicians and 85% (4,236) of the wives of male resident physicians responded to the questionnaire, which included questions on outcome of each pregnancy and number of hours worked. Resident physician women reported working twice as many hours per week during their pregnancies as did the wives of the male resident physicians. Between the two groups overall, investigators found no statistically significant differences in the proportion of pregnancies that ended in miscarriage, ectopic gestation, stillbirths, preterm delivery, or intrauterine growth retardation. However, three important findings were identified. First, premature labor requiring bed rest or hospitalization was nearly twice as common among the female resident physicians as among the male resident physicians’ wives (11.3% vs. 6.0%, p < 0.001). Second, preeclampsia or eclampsia was also twice as common among the resident physician women as the resident physician men’s wives (8.8% vs. 3.5%, p < 0.001). Third, for those resident physicians working 100 or more hours per week during the 3rd trimester, there was more than twice the risk of preterm delivery compared to those working fewer than 100 hours (10.3% vs. 4.8%, p = 0.04). Premature labor, preeclampsia/eclampsia, and preterm delivery (in women resident physicians working over 100 hours), were thus found to be significant problems for the pregnant resident physicians.
Another study validated these findings on pre-term labor and preeclampsia. An anonymous, cross-sectional survey of 4,674 Obstetrics and Gynecology resident physicians was conducted to assess pregnancy-related outcomes. The survey was administered before an in-service training exam and was returned with a 95.5% response rate. When factoring out surveys with errors, 4,357 remained for analysis. Female resident physicians were compared to their male resident physicians’ spouses. Of those who reported, roughly 70% of female resident physicians worked more than 80 hours per week during their pregnancy. Total hours worked by the comparison group (male resident physicians’ spouses/partners) were not recorded, but researchers did find that only 68.5% of male resident physicians had a spouse that worked. Investigators found that female resident physicians had a statistically significant higher risk of preterm labor (RR = 2.4, p = 0.03) and preeclampsia (RR = 5.7, p = 0.01), as well as another negative health outcome, fetal growth restriction (birth weight below the 10th percentile for gestational age, p = 0.002) when compared to the spouses of their male counterparts.
In another study, intrauterine growth restriction was found to also be a negative health effect of working excessive resident physician hours. Investigators surveyed 1,025 female board-certified obstetricians about their pregnancies before, during, and after residency. The response rate was 49%. The mean number of hours worked during residency was 78.9, compared to 36.4 before residency and 46.5 after residency. A critical finding was that infants delivered during residency were more likely to be born with intrauterine growth restriction compared to those delivered before or after residency (rates of 1.2%, 8.2%, and 1.0%, before, during, and after residency). Worse, the average birthweight of firstborn infants delivered during residency was found to be significantly lower than the birthweight of firstborn infants delivered before residency (3,146 g., SD 696 vs. 3525 g., SD 455, respectively; p < 0.001). Although mean birthweights were low in infants delivered after residency (3,263 g., SD 556; p < 0.005), they were still higher than birthweights of infants born during residency. The low birthweight rates (defined as any birthweight below 2500 g.) were 3.7%, 11.6%, and 2.6% before, during, and after residency, respectively.
Researchers have additionally hypothesized that the long hours of residency may cause more pregnancies to fail. Using the same data set, Klebanoff et al. also compared early-pregnancy complication rates in female resident physicians with those among partners of male resident physicians. The life-table probability of spontaneous abortion was 14.8% for female resident physicians and 12.6% for the partners of male resident physicians (RR = 1.18, 95% CI 0.96-1.45), a difference that was concerning, but that did not reach statistical significance.
In summary, these results point to increased risks for preterm labor requiring serious hospitalization, preeclampsia or eclampsia, and preterm delivery in female resident physicians. Other studies suggest that the children of resident physicians can also suffer from decreased birthweights and intrauterine growth restriction. The author of one study agreed that available research includes “sufficient findings to suggest that heavy exertion and fatigue may cause premature deliveries, decreased birthweights, and other complications in pregnant residents.” In a review of the literature on pregnancy complications of resident physicians, another author concluded, “[T]he greatest factor leading to poor pregnancy outcomes among physicians seems to be time spent working, particularly during late pregnancy.” The signers of this petition believe that even modest work-hour limitations would significantly reduce these adverse outcomes.
D. Percutaneous Injuries
In addition to the other health problems resident physicians face from working excessive hours, they suffer a greater rate of percutaneous injuries, such as needlesticks or cuts from medical equipment. These injuries are dangerous because they can transfer infectious diseases like Hepatitis C or HIV from an infected patient via blood. A prospective within-subjects cohort study of 2,737 interns, using a web-based survey, showed a substantially increased risk of percutaneous injury (PI) during day shifts after overnight call (extended work) compared to day shifts without a preceding overnight call (non-extended work), OR 1.61 (95% CI, 1.46-1.78). The mean duration of resident physicians’ work preceding those injuries occurring after an extended work shift was 29.1 consecutive hours. Fatigue was identified by resident physicians themselves as a leading cause of these injuries. Resident physicians who worked overnight calls were much more likely to say fatigue was involved (44%) than their counterparts who only worked a regular shift (18%) (p = 0.02). In sum, the authors concluded, “The association of these injuries with extended work duration is likely due to the adverse cognitive effects of the sleep deprivation associated with such extended work”.
General surgery and the surgical sub-specialties (e.g. Orthopedics, Neurosurgery, and Urology) are universally recognized for requiring trainees to work longer hours than any other medical specialties and having the longest training — five years or more. The operating room setting is particularly dangerous because of the numerous sharp instruments necessary to perform invasive procedures and surgical resident physicians — because they are learning new technical skills — are particularly susceptible to injury. An Annals of Surgery study from 2005 found that 20 to 38% of all procedures in one urban academic teaching hospital involved exposure to HIV, HBV or HCV. A study published in 2007 in the New England Journal of Medicine reported on a survey of 582 surgery resident physicians (83% response rate) at 17 medical centers. The survey found that by their final year of training, 99% of resident physicians suffered a needlestick injury. For 53% of those surgical resident physicians, the injury had involved a high-risk patient. Lack of time was the most common reason given for the cause of the injury (57%), followed by fatigue (15%).
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