Breathlessness, anxiety, depression and function - the BAD-F study: a cross-sectional, population prevalence study in adults.

INTRODUCTION: Breathlessness is associated with depression, but its relationship to anxiety or impaired function are less clear.

OBJECTIVES: This study evaluated associations between chronic breathlessness and: anxiety; depression; functional status in the general population.

METHODS: This cross sectional study of consenting adults (≥18 years) used an online survey. Quota sampling (n=3,000) was employed reflecting the 2016 national census for sex, age and place of residence. Other data included: Patient Health Questionnaire for Depression and Anxiety (PHQ-4); the modified Medical Research Council (mMRC) breathlessness scale and the Australia-modified Karnofsky Performance Scale (AKPS). Multinomial logistic regression assessed predictors.

RESULTS: 2977 respondents had all relevant scores; female- 51.2%; median age 45.0 (range 18-92). Prevalence of breathlessness (mMRC ≥ 2) was 2.4%; anxiety 6.0%; depression 2.7%; co-existing anxiety/depression 6.1% and poorer functional status (AKPS ≤60) 1.6%.In multinomial regression, depression, anxiety and co-existing anxiety/depression were predicted by younger age, longer duration of breathlessness, and poorer functional status. The highest proportions of people with breathlessness were found in the co-existing anxiety/depression group (10.6%) and depression only (8.8%).Poorest function was in the co-existing anxiety/depression group with 11.6%. The relationship between poorer functional status and co-existing anxiety/depression was significant (OR 0.90; 95%CI 0.89,0.92). Adjusted odds ratios for breathlessness and depression only was 3.0 (95% CI 1.2,7.8).

CONCLUSION: Clinically important breathlessness (mMRC ≥2) was associated with depression, anxiety and co-existing anxiety/depression. Poorer function that is associated with psychological morbidity in the general population requires further research.