Effect of twice daily inhaled albuterol on cardiopulmonary exercise outcomes, dynamic hyperinflation, and symptoms in secondhand tobacco-exposed persons with preserved spirometry and air trapping: a randomized controlled trial.

BACKGROUND: In tobacco-exposed persons with preserved spirometry (active smoking or secondhand smoke [SHS] exposure), air trapping can identify a subset with worse symptoms and exercise capacity. The physiologic nature of air trapping in the absence of spirometric airflow obstruction remains unclear. The aim of this study was to examine the underlying pathophysiology of air trapping in the context of preserved spirometry and to determine the utility of bronchodilators in SHS tobacco-exposed persons with preserved spirometry and air trapping. METHODS: We performed a double-blinded placebo-controlled crossover randomized clinical trial in nonsmoking individuals at risk for COPD due to exposure to occupational SHS who had preserved spirometry and air trapping defined as either a residual volume-to-total lung capacity ratio (RV/TLC) > 0.35 or presence of expiratory flow limitation (EFL, overlap of tidal breathing on maximum expiratory flow-volume loop) on spirometry at rest or during cardiopulmonary exercise testing (CPET). Those with asthma or obesity were excluded. Participants underwent CPET at baseline and after 4-week trials of twice daily inhalation of 180 mcg of albuterol or placebo separated by a 2-week washout period. The primary outcome was peak oxygen consumption (VO2) on CPET. Data was analyzed by both intention-to-treat and per-protocol based on adherence to treatment prescribed. RESULTS: Overall, 42 participants completed the entire study (66 ± 8 years old, 91% female; forced expiratory volume in 1 s [FEV1] = 103 ± 16% predicted; FEV1 to forced vital capacity [FVC] ratio = 0.75 ± 0.05; RV/TLC = 0.39 ± 0.07; 85.7% with EFL). Adherence was high with 87% and 93% of prescribed doses taken in the treatment and placebo arms of the study, respectively (P = 0.349 for comparison between the two arms). There was no significant improvement in the primary or secondary outcomes by intention-to-treat or per-protocol analysis. In per-protocol subgroup analysis of those with RV/TLC > 0.35 and ≥ 90% adherence (n = 27), albuterol caused an improvement in peak VO2 (parameter estimate [95% confidence interval] = 0.108 [0.014, 0.202]; P = 0.037), tidal volume, minute ventilation, dynamic hyperinflation, and oxygen-pulse (all P < 0.05), but no change in symptoms or physical activity. CONCLUSIONS: Albuterol may improve exercise capacity in the subgroup of SHS tobacco-exposed persons with preserved spirometry and substantial air trapping. These findings suggest that air trapping in pre-COPD may be related to small airway disease that is not considered significant by spirometric indices of airflow obstruction.

High prevalence of injection drug use and blood-borne viral infections among patients in an urban emergency department.

BACKGROUND: The opioid epidemic has led to an increase in the number of persons who inject drugs, and this population accounts for 12% of new human immunodeficiency virus (HIV) and 60% of new hepatitis C virus (HCV) infections in the United States annually. While persons who inject drugs disproportionately utilize the emergency department (ED), accurate data is lacking on the prevalence and patterns of injection drug use, and prevalence of co-occurring HIV and HCV infections among ED patients. OBJECTIVE: The primary outcome was to assess the prevalence of injection drug use and co-occurring HIV and HCV infection among patients presenting to an urban ED. METHODS: This was a cross sectional study conducted at an urban ED, with an annual census of 65,000 visits. A closed-response questionnaire was developed based on publicly available validated surveys to assess patterns of injection drug use and HIV and HCV infection status, and administered by trained research assistants to all registered adult patients during 4-hour blocks of time. RESULTS: Of the 2,319 eligible patients, 2,200 (94.9%) consented and completed the survey. 241 (11.0%) had ever used injection drugs, 103 (4.7%) currently used injection drugs, and 138 (6.3%) formerly used injection drugs. White patients age 25 to 34 years and white patients age 55 to 64 years had the highest prevalence of current (25.6%) and former (27.1%) injection drug use, respectively. Persons who use injection drugs had a higher prevalence of HCV infection (52.7% vs. 3.4%) and HIV infection (6.2% vs. 1.8%) than the rest of the population. CONCLUSION: A high prevalence of ED patients report injection drug use, and this population self-reports a high prevalence of HIV and HCV infection. Emergency departments are in a unique position to engage with this population with regards to substance use treatment and linkage to care for HIV and HCV infection.