Associations of psychosocial factors with health outcomes among youth with cystic fibrosis

Purpose: The purpose of this study was to examine the relationship of strains, resources, feelings, and behaviors about treatment adherence reported by youth with cystic fibrosis (CF) with repeated clinic measures of their pulmonary function and nutritional status. Methods: Linear mixed models, stratified by gender, adjusting for age, were used to examine the effects of strains, resources, and adherence behaviors on repeated pulmonary function and nutritional status measures. All 10-21 years old with CF at the Minnesota Cystic Fibrosis Center were invited by mail to participate. Of these 177 youth, 51% (43 boys, 47 girls) returned surveys. Forced expiratory volume in 1 sec and predicted weight-for-height were extracted from participants' clinic records for the 18 months following receipt of the survey. Results: Females showed significantly greater variability in repeated measures of pulmonary function and nutritional status compared to males. Parent-youth strains, physical strains, activity limitations, and cough suppression had significant effects on the 18-month mean of pulmonary function measures for females, but only physical strains had a significant effect for males. Conclusion: Compared to males, females experienced more strains and poorer treatment adherence, which may be factors associated with declines in pulmonary function observed among females with CF during the adolescent years.