Hospitalized patients with alcohol use disorder (AUD) and community-acquired pneumonia harbor resistant organisms less often than hospitalized patients with community-acquired pneumonia (CAP) without AUD, according to a study published in JAMA Network Open. In addition, researchers noted that the higher age-adjusted mortality risk seen in patients with AUD appears to a result of differences in comorbidities, while the greater use of hospital resources may be a result of alcohol withdrawal.
This retrospective cohort study included 137,496 adults with CAP admitted to hospitals in the United States between July 2010 and June 2015. Data were obtained from the Premier Healthcare Database. Generalized linear mixed models were performed to compare the causes, treatment, and outcomes of CAP in patients with and without AUD, and to identify associations between outcomes and alcohol withdrawal, comorbidities, and any residual effects of alcohol. Outcomes included pneumonia cause, clinical deterioration, antibiotic treatment, cost, length of stay, and inpatient mortality. Alcohol use disorder was defined using International Classification of Diseases, Ninth Revision, Clinical Modification codes.
Among the total 137,496 patients (mean age, 69.5 years; 70,358 women, 67,138 men), 3.5% had an AUD. Patients with an AUD were more often men (77.3% vs 47.8%; P <.001), were younger than patients without an AUD (median age, 58.0 vs 73.0 years; P <.001), were more often insured by Medicaid (21.8% vs 8.1%; P <.001) and more often had a principal diagnosis of aspiration pneumonia (10.9% vs 9.8%; P <.001), respiratory failure (9.3% vs 5.5%; P <.001), or sepsis (38.6% vs 30.7%; P <.001). Patients who had AUD tended to have more comorbidities, including chronic liver disease (20.4% vs 2.5%; P <.001), weight loss (20.5% vs 12.5%; P <.001), psychoses (11.0% vs 6.1%; P <.001), and abuse of drugs other than alcohol (17.8% vs 2.7%; P <.001).
Moreover, patients with AUD commonly presented with more severe illness, and were more likely to be admitted to the intensive care unit (39.0% vs 24.3%; P <.001) and to receive vasopressors (11.3% vs 6.2%; P<.001) or invasive mechanical ventialtion (16.4% vs 7.5%; P <.001)
Compared with patients without AUD, patients with AUD had a higher incidence of Streptococcus pneumoniae (43.7% vs 25.5%; P <.001) and a lower incidence of organisms resistant to guideline-recommended antibiotics (25.0% vs 43.7%; P <.001), and were treated with piperacillin-tazobactam more often (26.2% vs 22.5%; P <.001) and with anti-methicillin-resistant Staphylococcus aureus agents equally as often (32.9% vs 31.8%; P =.11).
After adjusting for insurance and demographic characteristics, AUD was associated with increased costs (risk-adjusted geometric mean ratio, 1.33; 95% CI, 1.28-1.38), longer hospitalization (risk-adjusted geometric mean ratio, 1.24; 95% CI, 1.20-1.27), and higher mortality (odds ratio, 1.40; 95% CI, 1.25-1.56). After additional adjustment was made for risk factors for resistant organisms and differences in comorbidities, AUD was no longer associated with higher mortality, but remained associated with increased costs and longer hospitalization as well as late mechanical ventilation. Models separating patients with alcohol withdrawal syndrome showed that the poorer outcomes for AUD patients were confined to that subgroup.
Study investigators concluded that despite a few limitations, including a reliance on International Classification of Diseases, Ninth Revision, Clinical Modification codes that may have led to a failure to identify some AUD cases, the poorer age-adjusted outcomes for the 1 in 30 patients hospitalized with pneumonia who also had AUD may also be a result of alcohol withdrawal syndrome in these patients, which results in longer hospital stays. Researchers therefore highlighted that “routine CAP therapy and close monitoring for [alcohol withdrawal syndrome].”
Gupta NM, Lindenauer PK, Yu PC, et al. Association between alcohol use disorders and outcomes of patients hospitalized with community-acquired pneumonia [published online June 7, 2019]. JAMA Netw Open. doi: 10.1001/jamanetworkopen.2019.5172