Secondhand Tobacco Smoke Exposure Among Hospitalized Nonsmokers With Coronary Heart Disease

Exposure to secondhand tobacco smoke (SHS) increases adult nonsmokers’ risk of cardiovascular disease by 25% to 30%.¹ Among nonsmokers hospitalized with acute coronary syndrome, SHS exposure is associated with a higher likelihood of subsequent cardiovascular and all-cause mortality as well as reinfarction.^2,3 Hospitalized nonsmokers with coronary heart disease (CHD) should avoid SHS exposure after discharge, but little is known about the frequency of SHS exposure in this population or whether clinicians (including nurses, nurse practitioners, physician's assistants, and physicians) address it. The present study assessed self-report and biochemical measures of SHS exposure among hospitalized nonsmokers with CHD and explored patients’ beliefs and the clinicians’ actions about SHS.

The study was approved by the Massachusetts General Hospital/Partners Health Care System Institutional Review Board. Participants provided oral consent; they received no financial compensation. The study was conducted in the inpatient cardiac service of Massachusetts General Hospital, Boston. Eligible patients were aged 18 years or older, reported no tobacco or nicotine replacement use, had ischemic CHD as an admission diagnosis, spoke English, were medically stable, had no significant cognitive impairment, and were hospitalized for 48 hours or less. Consenting patients had a bedside interview regarding their demographics; SHS exposure in their home, car, and work; home and car rules about smoking; beliefs about the risk of SHS exposure; and interventions regarding SHS exposure by “a doctor, a nurse, or other health care professional.”⁴ A saliva sample was collected for an assay of cotinine, a nicotine metabolite with a 16-hour half-life.^5,6 The limit of quantitation of the assay was 0.20 ng/mL for the first 112 samples and 0.05 ng/mL for the last 72 samples (to convert cotinine to nanomoles per liter, multiply by 5.675). The discharge diagnosis was obtained from the medical records.

Between May 25, 2010, and January 27, 2011, a total of 3152 nonsmokers were admitted to the cardiac service; of these, 2192 individuals (69.5%) had a CHD diagnosis, 230 (7.3%) met the eligibility criteria, and 214 (6.8%) enrolled in the study. The primary reasons for ineligibility were more than 48 hours since admission (41.7%) and discharge before the research staff could visit (34.5%). Table 1 reports characteristics of the sample.

Secondhand tobacco smoke exposure was reported by 47 patients (22.0%) in the 30 days before hospital admission and by 33 patients (15.4%) in the 7 days before admission (Table 1). Twenty-nine patients (13.6%) lived with a smoker, who was most likely an adult child or a spouse. Two-thirds of the patients (67.8%) reported having a household smoking ban, and 72.3% of the patients with a car reported having a car smoking ban.

Among the 184 individuals with sufficient samples for analysis, 15 (8.2%) had detectible cotinine (≥0.20 ng/mL). Among the 72 saliva samples analyzed with the more sensitive assay, 29 (40.3%) had detectable cotinine (≥0.05 ng/mL) (Table 1).

Most patients (89.7%) believed that SHS was harmful to nonsmokers’ health (Table 2). Although 56.5% of the respondents believed that SHS exposure increased nonsmokers’ risk of “heart attack,” 22.0% disagreed and 21.5% did not know. Similar results were found when patients were asked if SHS exposure increased their own risk of “heart attack” (Table 2). Half of the patients were “not at all” worried about their SHS exposure.

Only 37 patients (17.3%) recalled that a hospital physician or nurse had asked about their SHS exposure since admission. Only 21 (9.8%) had been asked if they lived with a smoker, and only 3 (1.4%) individuals were advised in the hospital to keep their home or car smoke free.

The findings of this study make a strong case for the need to address SHS exposure more effectively in inpatient cardiology practice. Nonsmokers who were hospitalized with CHD were rarely screened for SHS exposure or advised to avoid it, even though 15.4% reported recent SHS exposure and 40.3% had detectable levels of a biomarker of SHS exposure. It is likely that SHS exposure is similarly overlooked in outpatient cardiology practice. Hospitals and health care systems are missing an opportunity to identify and intervene in this major modifiable cardiovascular risk factor.

Corresponding Author: Nancy A. Rigotti, MD, Tobacco Research and Treatment Center, Department of Medicine, Massachusetts General Hospital, 50 Staniford St, Ninth Floor, Boston, MA 02114 (nrigotti@partners.org).

Published Online: November 10, 2014. doi:10.1001/jamainternmed.2014.5476.

Author Contributions: Drs Japuntich and Rigotti had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Study concept and design: Japuntich, Shenhav, Park, Winickoff, Rigotti.

Acquisition, analysis, or interpretation of data: Japuntich, Eilers, Shenhav, Winickoff, Benowitz, Rigotti.

Drafting of the manuscript: Japuntich, Winickoff, Rigotti.

Critical revision of the manuscript for important intellectual content: Eilers, Shenhav, Park, Winickoff, Benowitz, Rigotti.

Obtained funding: Park, Winickoff, Rigotti.

Administrative, technical, or material support: Japuntich, Eilers, Shenhav, Winickoff, Benowitz.

Study supervision: Japuntich, Park, Rigotti.

Conflict of Interest Disclosures: Dr Park has received a grant from Pfizer for varenicline for a clinical trial funded by the National Cancer Institute. Dr Benowitz has consulted for several pharmaceutical companies that market smoking cessation medications and has been a paid expert witness in litigation against tobacco companies. Dr Rigotti has been an unpaid consultant for Pfizer and received travel expenses to a consultant meeting, has been an unpaid consultant to Alere Wellbeing, and receives royalties from UpToDate, Inc. No other disclosures were reported.

Funding/Support: Funding for this study was supported by Flight Attendant Medical Research Institute grant 082472-CIA. This work was supported in part by Career Development Award 1IK2CX000918-01A1 to Dr Japuntich from the US Department of Veterans Affairs Clinical Sciences Research and Development Service.

Role of the Funder/Sponsor: Flight Attendant Medical Research Institute had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Disclaimer: The contents of this article do not represent the views of the Department of Veterans Affairs or the US government.

Additional Contributions: The cardiology nursing staff at the Massachusetts General Hospital screened patients for this study; Michele Reyen, MPH, Tobacco Research and Treatment Center, Massachusetts General Hospital, helped with the study start-up; Yuchiao Chang, PhD, Division of General Internal Medicine, Department of Medicine, Harvard Medical School, conducted the data analysis; and Joanna Streck, BA, Tobacco Research and Treatment Center, Massachusetts General Hospital, assisted with manuscript preparation. These individuals did not receive compensation beyond their salaries.