Background: While patients' personality has been thought to affect all_ergic diseases, the association of asthma and psychological factors is still debated. Stress is believed to predispose to asthma, but no clear evidence of causality has been found. We have studied the role of psychological factors in prevalent as well as in incident asthma cases among the adult population.
Methods: A total of 11540 adults initiall_y aged 18–45 years responded to three questionnaires in 1975, 1981, and 1990, respectively. The association of psychological factors (including extroversion and neuroticism scales, subjective stress, and life satisfaction) and prevalent asthma was studied, as well as the predisposing effect of these factors on the risk of adult onset asthma. Logistic regression was used for risk calculations.
Results: Low life satisfaction was associated with asthma prevalence (age- and sex-adjusted OR=2.27: 1.04–4.93 for prevalent asthma among those with low life satisfaction compared to those with high life satisfaction), as was neuroticism (age and sex-adjusted OR=1.78:1.12–2.84 for those with a high neuroticism score compared to those with a low score). A high extroversion score was significantly associated with the risk of adult onset asthma among women (age-adjusted OR=2.72: 1.44–5.12 for new asthma among those with high score compared to those with a low extroversion score).
Conclusions: No specific personality type is associated with adult onset asthma, but there is a significant sex difference in the effect of psychological factors in asthma risk. A high extroversion score is a strong predictor of incident asthma among women. Prevalent asthma decreases life satisfaction and is associated with a high neuroticism score.