Non-respiratory symptoms and well-being in asthmatics from a general population sample

Different instruments have been developed to assess health-related quality of life (HRQL) in asthma patients. However, relatively few studies have assessed HRQL in asthma patients from a general population, and it is still unclear which instrument is most suitable. The purpose of this study was to compare HRQL in clinically verified asthmatics with subjects with respiratory symptoms without asthma and with subjects with no respiratory symptoms from a general population. The generic instrument Gothenburg Quality of Life (GQL) was used. A secondary aim was to study if GQL had any prognostic value in asthma.

A cohort of three age groups in Sweden was investigated in 1990 using a respiratory questionnaire and GQL. The cohort consisted of 616 subjects with asthma, 488 subjects with respiratory symptoms but no asthma, and 347 subjects without respiratory symptoms. The participants were also investigated by spirometry and allergy testing. In a follow-up study, subjects were identified who had persistent and improved asthma.

The prevalence of 28 of the 30 common symptoms in GQL was significantly increased (p < 0.001) in subjects with asthma as compared to non-asthmatics. All symptoms in the domains heart and lung, head, musculoskeletal, tension, and depression were significantly increased among the asthmatics. The asthmatics also rated their physical well-being lower (p < 0.001) than subjects with no respiratory symptoms. Subjects with persistent asthma had a significantly higher prevalence of 7 of the 30 symptoms and lower social well-being than subjects showing improvement in asthma during the follow-up. All differences remained significant after adjusting for age, sex, and smoking habits.

Subjects with asthma had different symptom-profiles compared to those of non-asthmatics, with a higher prevalence of both respiratory and non-respiratory symptoms. Asthma is also a disease that is related to low well-being. The use of quality-of-life questionnaires such as the GQL may provide useful information for evaluating the non-respiratory aspects of asthma as well as for assessing the impact of disease on health status and well-being.