Unhealthy Substance Use Is Associated with Heart Failure Hospital Encounters

Unhealthy substance use complicates the management of chronic medical conditions such as heart failure. This retrospective cohort study investigated whether unhealthy use* of a number of substances—excluding tobacco—was associated with heart failure hospital encounters and all-cause mortality. Medical records for 11,268 adult patients with heart failure diagnoses from one California hospital system were examined for the years 2005–2016.

• Unhealthy substance use was documented in 15% of heart failure patients during the study period.
• Several substances were associated with hospital encounters for heart failure: methamphetamine (5% prevalence, incidence rate ratio [IRR] 2.0), opioids (8% prevalence, IRR 1.5), and alcohol (5% prevalence, IRR 1.5).
• Unhealthy substance use was not associated with all-cause mortality.

* Defined by authors as having a documented ICD-9 diagnosis of “substance abuse” or positive urine drug test.

Comments: In this study, unhealthy substance use was common and associated with negative heart failure outcomes. This sample’s high prevalence of methamphetamine use may not generalize to the entire US; however, methamphetamine is cardiotoxic and its use is increasing. The authors did not control for tobacco use, which at least in part explains the observed association between substance use and hospitalizations.

Aaron D. Fox, MD

Reference: Nishimura M, Bhatia H, Ma J, et al. The impact of substance abuse on heart failure hospitalizations. Am J Med. 2019 [Epub ahead of print]. doi: 10.1016/j.amjmed.2019.07.017.