Schizophrenia has a unique contribution to the facilitation of chronic obstructive pulmonary disease (COPD), which may extend beyond the effect of smoking, a new study found. The nationally representative cohort study was designed to assess the odds and cumulative probability of COPD and ischemic heart disease (IHD) among patients with schizophrenia (n=10,502) and a matched sample of smoking healthy controls. Researchers found:
- After adjusting for clinical and demographic factors, smoking patients with schizophrenia had a higher probability of receiving a diagnosis of COPD vs healthy controls.
- The probability of having COPD increased more rapidly in smoking patients with schizophrenia, yet the opposite trajectory prevailed for IHD.
- Patients with schizophrenia may be underdiagnosed with IHD.
Krieger I, et al. Increased risk of smoking-related illnesses in schizophrenia patients: A nationwide cohort study. [Published online ahead of print August 6, 2019]. Schizophrenia Res. doi: 10.1016/j.schres.2019.07.058.
It has been reported that up to 60% of patients with schizophrenia are smokers, a proportion that is three times that of the general population. Additionally, although smoking rates have declined among the general population in developed countries this trend has not occurred in those with psychiatric disorders. While findings of this study were somewhat counter-intuitive in that there were reverse trends for chronic obstructive pulmonary disease (COPD) vs. ischemic heart disease (IHD), results still underscore the fact that individuals with schizophrenia are at risk for developing longer-term medical complications associated with smoking. Care approaches that feature prevention of smoking behavior as well as smoking cessation/reduction efforts and screening for cardiovascular risk in current smokers, should all be part of a comprehensive package of care for those with serious mental illnesses such as schizophrenia. —Martha Sajatovic, MD, Professor of Psychiatry and of Neurology; Willard Brown Chair in Neurological Outcomes Research; Director, Neurological and Behavioral Outcomes Center, University Hospitals Cleveland Medical Center; Case Western Reserve University School of Medicine.