Early Detection of Respiratory Disorders in Psychosis

Asthma and chronic obstructive pulmonary disease (COPD) are chronic respiratory disorders with high prevalence in the general population. Tobacco smoking is the leading risk factor for COPD, and has been associated with higher risk for uncontrolled asthma. Tobacco smoking is widely extended in the general population and is highly associated with cannabis use, which is the most consumed illicit drug in Spain. Other described risk factors for poor lung function are metabolic alterations such as insulin resistance and diabetes, and even abdominal obesity. Patients with psychosis present remarkably higher prevalence of tobacco and cannabis consumption than the general population and higher risk for developing metabolic alterations such as obesity and diabetes at the long-run.

Despite these premises, the effect of metabolic alterations and tobacco and cannabis smoking on the respiratory health has been poorly studied. Previous studies, mainly based on patients' registers showed an increased risk for COPD and uncontrolled asthma in patients with psychosis. Few studies have analysed this relation using lung function tests (spirometry), reporting reduced spirometry values in patients with schizophrenia compared with healthy controls. But little data is available on the possible causative relation of smoking (tobacco and cannabis) and metabolic alterations of COPD and un-controlled asthma in psychosis.

Based on the available scientific evidence, the investigators hypothesize that patients with psychosis will present differences in prevalence and severity of lung disease and poorer lung function, compared with the general (non-psychiatric) population, probably related to smoking (tobacco and cannabis) and metabolic alterations.

The research project would be implemented as part of a larger prospective longitudinal study on first episode non-affective psychosis, in the First Episode Psychosis Clinical Program (PAFIP). In particular, the project would be part of the "10 PAFIP study", in which those patients that had been included in the PAFIP program 10 years ago will be extensively evaluated (e.g.: clinical, neuroimaging, neuro-psychological, and metabolic evaluations) in order to analyse the long-term progress of the psychosis.

Regarding the present project, a respiratory health status evaluation would be carried out cross-sectionally at this time-point (after 10 years of initiated the psychotic illness). Lung health status would be evaluated through functional test using spirometer. The clinical respiratory status would be evaluated using the following scales: the COPD Assessment Test (CAT) and the modified Medical Research Council (mMRC) Questionnaire.