Introduction: Psychological issues are common in patients with chronic disabling diseases such as asthma. National guidance recommends that specialist asthma clinic attendees should complete questionnaires screening for psychological comorbidities. However, completing these in addition to asthma specific questionnaires can be burdensome. In order to investigate whether anxiety and depression questionnaires can be used in a targeted manner, this study investigates the correlation between the respective scores. We hypothesize that there is correlation between asthma-specific and anxiety/depression questionnaire scores.
Methods: Three-hundred individuals with poorly controlled asthma attending a specialist clinic were asked to complete Asthma Control Questionnaire (ACQ), mini-Asthma Quality of Life Questionnaire (mini-AQLQ), Generalized Anxiety Disorder (GAD-7) and Patient Health Questionnaires (PHQ-9). A Pearson correlation coefficient was generated and area under ROC and confusion matrices were used to assess correlation.
Results: 49% and 47% of patients completing the GAD-7 or PHQ-9 questionnaires, respectively had scores above the screening level for co-morbid anxiety and depression. Additional questionnaires were often incomplete (GAD-7 = 150 and PHQ-9 = 140). GAD-7 and PHQ-9 correlated with ACQ and mini-AQLQ (all p = <0.001, r values 0.53-0.65). Asthma-specific questionnaire scores were predictive of GAD-7 and PHQ-9 scores (AUCs of 0.78 to 0.84). 75% of patients with a mini-AQLQ score of <3 met the threshold GAD-7 and PHQ-9 score of 10.
Conclusions: ACQ and mini-AQLQ correlate with GAD-7 and PHQ-9 amongst specialist asthma clinic attendees. A mini-AQLQ >3 suggests patients are unlikely to have anxiety or depression. These findings could be used to identify patients requiring formal screening for psychological co-morbidity.
Keywords: Asthma; GAD-7; PHQ-9; anxiety; depression; questionnaires.