Background: In 1981, the Royal Australian Air Force (RAAF) introduced an intensive health promotion program (HPP), the purpose of which was to control preventable diseases, particularly cardiovascular disease (CVD), linked to lifestyle-related risk factors. However, the RAAF HPP's effectiveness had not been appropriately evaluated since its implementation.
Hypothesis: The RAAF HPP's interventions have reduced, beyond secular trends, the prevalence of lifestyle-related CVD risk factors.
Methods: Retrospective cross-sectional risk factor prevalence surveys of randomly selected RAAF pilots and navigators were conducted for the years 1980, 1983 and 1989. The survey results for RAAF subjects were compared with the results obtained for demographically similar subjects participating in National Heart Foundation (NHF) Risk Factor Prevalence Study (RFPS) surveys for the same periods, using chi2 and Mantel-Haenszel (M-H) chi2 tests, and 1-way and 2-way ANOVA.
Results: Over the survey periods, the prevalence of overweight and obesity decreased by 8% in RAAF subjects and increased by 7% in NHF subjects, and mean total serum cholesterol decreased by 8% in RAAF subjects while remaining static in NHF subjects. Participation in vigorous physical activity increased among RAAF, but not NHF, subjects. The results for most other risk factors showed significant differences between RAAF and NHF subjects, but trends were comparable over survey periods.
Conclusions: On balance, reductions in the prevalence of overweight and obesity, and mean serum cholesterol in RAAF subjects were probable effects of the RAAF HPP. Other observed differences in CVD risk factors between RAAF and NHF groups were attributable to the RAAF aircrew selection process, or other RAAF-specific influences. The study thus provides qualified support for the hypothesis, although effects were less evident in older RAAF subjects.