Health-related quality of life predicts onset of asthma in a longitudinal population study.

Background: Health-related quality of life (HRQL) has been increasingly used as an outcome measure in asthma, but less is known about the prognostic implication of low health-related quality of life. The purpose of this study was to investigate if a set of quality of life measures could predict onset of asthma.

Methods: In the baseline study 391 subjects without asthma answered a respiratory questionnaire and the Gothenburg Quality of Life (GQL) instrument in 1990. The GQL questionnaire included two parts: (1) the prevalence of HRQL-related symptoms and (2) well-being scores for physical, mental and social dimensions. The participants were also investigated with spirometry and allergy testing. In 2003, the same respiratory questionnaire that had been used in 1990 was sent. There were 290 responders, of whom 22 subjects had developed asthma.

Results: Participants who had developed asthma by the follow-up had a higher prevalence of sleep disturbances (30% vs. 10%), problems with chest pain (16% vs. 2%), depression (40% vs. 20%) difficulty relaxing (40% vs. 13%) and constipation (25% vs. 2%) at baseline than participants who did not develop asthma (p<0.05). Subjects who developed asthma also scored significantly lower on well-being variables as sleep, energy, mood, patience, memory, appetite, fitness and sense of appreciation outside home. These differences remained after adjusting for age, sex, smoking habits, asthma heredity, socioeconomic groups and building dampness.

Conclusion: Participants with low health-related quality of life at baseline were more likely to report having developed asthma 12 years later.