Associations between illness perceptions and health-related quality of life in adults with cystic fibrosis.

OBJECTIVE: The objective of this work was to examine the relationship between illness perception, health status, and health-related quality of life (HRQOL) in a cohort of adults with cystic fibrosis (CF).
METHODS: In the Project on Adult Care in Cystic Fibrosis, we administered five subscales (Illness Consequences, Illness Coherence, Illness Timeline--Cyclical, Personal Control, and Treatment Control) of the Illness Perception Questionnaire--Revised (IPQ-R). Multivariable linear regression analyses explored the associations between illness perception, health status, symptom burden, and physical and psychosocial HRQOL, as measured by various domains of the Cystic Fibrosis Questionnaire--Revised (CFQ-R).
RESULTS: Among the 199 respondents (63% female; mean age, 36.8 ± 10.2 years), IPQ-R scores did not differ on age, gender, or lung function. In multivariable regression models, neither clinical characteristics nor physical or psychological symptom burden scores were associated with CFQ-R physical domains. In contrast, higher scores on Illness Consequences were associated with lower psychosocial CFQ-R scores. Higher scores on the Illness Coherence and Personal Control scales were associated with higher psychosocial CFQ-R scores.
CONCLUSION: Adults with CF report a high understanding of their disease, feel that CF has significant consequences, and endorse both personal and treatment control over their outcomes. Illness perceptions did not vary with increased age or worsening disease severity, suggesting that illness perceptions may develop during adolescence. Illness perceptions were associated with psychosocial, but not physical, aspects of HRQOL. Efforts to modify illness perceptions as part of routine clinical care and counseling may lead to improved quality of life for adults with CF.