E. Hanson, J. Fleisher, R. Jackman, J. Dovenbarger, D. Uguccioni, E. Thalmann, E. Cudahy. Naval Submarine Medical Research Laboratory, Groton, CT 06349-5900. Divers Alert Network, Duke University Medical Center, Durham, NC 27710.
Background: Both the medical and popular literature suggests that a significant proportion of the recreational scuba diving population may have chronic medical conditions that affect their fitness to dive. The purpose of this study was to characterize the demographics and illness prevalence of a recreational scuba diving population.
Methods: The research design is a cross-sectional demographics and prevalence study of randomly selected members of Divers Alert Network who were sent a validated, anonymous four-page questionnaire regarding diagnosed health conditions, demographics and dive habits. 3,000 questionnaires were mailed out, 1,654 (55.1 percent) were completed and returned (approximately 1 percent of DAN members).
Results: 1,653 were analyzed; one questionnaire was excluded because the respondent was an active duty Special Forces diver. Demographics: 1,229 (74.3 percent) were male and 408 (24.6%) were female. Average age was 40 (SD +/- 11) with a range from 13 to 84. Age breakdown by gender was not statistically different. In our sample, 43.1 percent had body mass index (BMI) calculated as ideal, 40 percent as overweight and 13.6 percent as obese according to NIH recommended BMI guidelines for males and females.
Illness Prevalence: Hypertension was the number one diagnosed condition at 9.7 percent. Asthma was second at 8.1 percent (includes childhood asthma resolving by age twelve, 4.1 percent). Therefore the prevalence of active asthmatic disease in our population is 4.2 percent. Other prevalent conditions in decreasing order of occurrence include: tinnitus (8.1 percent), migraine (6.0 percent), hearing impairment (5.3 percent), ruptured ear drum (5.4 percent), head injury with loss of consciousness (5.4 percent), depression requiring medication (4.8 percent). Severe allergies (2.4 percent) and decompression sickness (2.1percent).
Conclusions: Although the data applies to a select population of divers, it suggests that a substantial number of certified recreational scuba divers may have potentially disqualifying medical conditions according to the Recreational Scuba Training Council's guidelines for screening potential divers. In interpreting the results, the following limitations need to be considered: self-reported nature of the study, select population and a 55.1 percent response rate.