What Factors Are Associated With Suicide in Heavy Smokers With or Without COPD?

Factors associated with risk of suicide/overdose in those who have smoked heavily and have or are at risk for chronic obstructive pulmonary disease (COPD) are current smoking, use of sedatives/hypnotics, and dyspnea. Moreover, in this population, a lower risk for suicide/overdose is seen in individuals who are older, have higher body mass index (BMI), or are Black. These are among study findings published in Chest.

Investigators sought to explore which clinical variables predict death by suicide or an overdose of indeterminate intent in a large cohort of individuals with COPD who smoke heavily. The researchers analyzed data from the COPDGene study (ClinicalTrials.gov identifier: NCT00608764), a 21-center, longitudinal, prospective study of individuals (aged 45 to 80 years) who currently or formerly have smoked heavily (ie, at least a 10 pack-year history of smoking), both with and without airway obstruction. The prospective cohort study offered the opportunity for the researchers to stratify suicide risk among individuals with well-characterized COPD.

COPDGene study patient data are updated during regular visits during each phase of the longitudinal study, which is currently in phase 3. The current study included individuals who currently or formerly smoked who had completed the COPDGene study phase 1 (2007 to 2012) visit. If available, the values of variables were updated during the phase 2 (2012 to 2017) and phase 3 (2018 to present) visits.

Data from a total of 9930 participants from the COPDGene study were assessed. All participants were followed for a mean of 8 years. The primary cause of adjudicated deaths was identified from death certificates, medical records, and family reports. Death by suicide/overdose was evaluated as the primary outcome with the use of Cox regression, adjusted for sex, age, race, body mass index (BMI), pack-years, current smoking status, airflow limitation (percent predicted forced expiratory volume in 1 second [FEV₁]), modified Medical Research Council [mMRC] Dyspnea Scale score ≥2), 6-minute walk distance, use of supplemental oxygen, and severe COPD exacerbations in the previous year.

The mean participant age [SD] was 59.6 [9.0] years. Overall, the study cohort was 47% female, 33% Black, and 67% White. The mean [SD] FEV₁ percent predicted was 76.1 [25.5].  A total of 63 individuals died by suicide or overdose. Factors shown to be associated with the risk for suicide/overdose included current smoking (hazard ratio [HR], 6.44; 95% CI, 2.64-15.67; P <.001), use of sedatives/hypnotics (HR, 2.33; 95% CI, 1.24-4.38; P =.009), and dyspnea (HR, 2.23; 95% CI, 1.34-3.70; P =.002).

Lower risk for suicide/overdose was associated with older age (HR per decade, 0.45; 95% CI, 0.31-0.67; P <.001), higher BMI (HR, 0.95; 95% CI, 0.91-0.99; P =.03), and being Black (HR, 0.41; 95% CI, 0.23-0.74; P =.003). The severity of airflow limitation (ie, FEV₁  percent predicted) was not associated with the risk for suicide.

Limitations of the current study include: basing COPD diagnosis self-report rather than clinical assessment; lack of consideration for disease severity; and a lack of data on socioeconomic status, substance use disorders, other comorbid mental health conditions as well as history of inpatient psychiatric hospitalizations or history of suicidal attempts or gestures.

Study authors concluded that “Among heavy smokers with and without airway obstruction, current smoking was the strongest risk factor, associated with a six-fold greater risk for suicide/overdose, followed by sedative/hypnotics use and

dyspnea (mMRC≥2). Objective measures of COPD severity were not associated with suicide/overdose.” These results suggest that “the subjective experience of COPD is important in assessing suicide risk among heavy smokers. Further work is required to determine the generalizability of these results in other healthcare settings, non-smoking or lighter smoking populations, and the role of psychological distress,” the researchers noted.

Disclosure: Some of the study authors have declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures. 

Reference

Adviento BA, Regan EA, Make BJ, et al; COPDGene Investigators. Clinical markers associated with risk of suicide or drug overdose among heavy smokers – a longitudinal follow-up study of the COPDGene cohort. Chest. Published online September 24, 2022. doi:10.1016/j.chest.2022.09.022