Body composition change during the intern year of emergency medicine residency

Abstract

Study objectives: Interest in the often extreme workloads of residents has led to changes in the American Council on Graduate Medical Education guidelines. Although this will certainly have a positive effect on resident health, the fitness and nutritional needs of residents have still not been addressed. Long work hours and related stress, combined with limited access to exercise and good nutrition, can quickly lead to unhealthy body composition changes. The objective of this study is to determine whether a measurable detriment to body composition can be detected during a 6-month period at the beginning of residency. Methods: This was a prospective cohort study of first-year emergency medicine residents at 2 Midwestern, urban, tertiary trauma centers. This study was conducted from August 2002 through February 2004. Two classes of residents were included in this study. Each class was eligible for inclusion in August of their intern year. Entry and 6-month measurements were taken. Physical measurements included age, sex, height, weight, and bioimpedance. Bioimpedance was measured using the Bioanalogics ELG II ElectroLipoGraph. The Bioanalogics QuickComp Portable Body Composition program was used to calculate percentage of body fat and percentage of lean body mass. Body mass index was calculated using the National Institutes of Health multiplier. Statistical significance was analyzed using SPSS software (version 10.00). Repeated-measures analysis of variance and Student's t test for paired means were calculated. Results: Thirty-one residents participated in this study; 8 were lost to follow-up. The subject group had a mean entry age of 28 years, with 65.2% male subjects. Comparison of means showed a mean weight increase of 2.4% ( P =.004). Weight gain was seen in 14 subjects, with an average gain of 7.9 lbs (3.6 kg). Weight gain was only significant, defined as 8 to 20 lbs (3.6 to 9.1 kg), in 7 subjects. During the study period, there was a 13% increase in those identified as overweight according to the National Institutes of Health recommendations on body mass index. Percentage of lean body mass decreased 3.3% ( P =.033), whereas percentage of body fat increased 13.3% ( P =.033). Actual mass of body fat in pounds increased 18.6% ( P =.011). Conclusion: Even with more limits on work hours, residents have limited time for exercise and nutrition. Often their access is limited to what the hospital provides. Additional attention needs to be paid to this issue to maximize resident performance. It is shown that even in as short as a 6-month period, interns experience detrimental changes in body composition. Although weight change is not clinically significant, it can mask underlying changes in body composition. Significant increases in body fat percentage, accompanied by decreases in percentage of lean body mass, were seen. The study was limited because subjects were nonblinded and had access to the results of their measurements, which might account for somewhat of a study effect, and it is suggested that a blinded study might show a greater increase in weight. Future studies might also concentrate on standardizing the residency affect by correcting for exercise and dietary outliers.