The Association Between Secondhand Smoke Exposure and Survival for Patients With Heart Failure

Air pollution is associated with abnormal left ventricular diastolic function: a nationwide population-based study

BACKGROUND

Air pollution is a growing public health concern of global significance. Till date, few studies have explored the associations between air pollutants and cardiac imaging phenotypes. In this study, we aim to explore the association of ambient air pollution and abnormal left ventricular diastolic function (ALVDF) among a large-scale free-living population.

METHODS

The participants were from a national representative large-scale cross-sectional study, i.e., the China Hypertension Survey (CHS), 2012-15. After exclusion, 25,983 participants from 14 provinces and 30 districts in China were included for the final analysis. The annual average ambient PM2.5, PM10 and NO2 concentrations were obtained from the chemical data assimilation system (ChemDAS). The clinical evaluation of left ventricular function was conducted in the survey field which was based on echocardiography. Grading diastolic dysfunction was based on Recommendations for the evaluation of left ventricular diastolic function by echocardiography (2009).

RESULTS

The mean age of 25,983 participants was 56.8 years, 46.5% were male, and the crude prevalence of GradeI-III ALVDF were 48.1%, 1.6% and 1.1%, respectively. The ORs (95% CI) for ALVDF in the fully adjusted model were 1.31 (1.11-1.56), 1.11 (1.01-1.21) and 1.18 (0.90-1.54) for an increase of 10 μg/m3 of PM2.5, PM10 and NO2, respectively. And for different grades of ALVDF, elevated concentration of PM2.5 and PM10 exposures significantly increased the risk of gradeIinstead of gradeII ~ III ALVDF. There was a positive linear and "J" shape concentration-response association between annual average ambient PM2.5 and NO2 and the ALVDF risk assessed by the restricted cubic spline. The exposure level of most participants to PM10 was less than 130 μg/m3, and the risk of ALVDF increased significantly with the concentration rise.

CONCLUSIONS

This large-scale nationwide population study demonstrated a significantly positive association between ambient PM2.5, PM10 and NO2 with ALVDF, especially for mild ALVDF. The functional abnormality may partially explain the enhanced cardiovascular morbidity and mortality associated with air pollution, which highlights the importance of appropriate interventions to reduce ambient air pollution in China.

Angina Outcomes in Nonsmokers Exposed to Secondhand Smoke: Results from the National Health and Nutrition Examination Survey 2007–2018

Objective  The aim of the study is to examine the relationship between secondhand smoke (SHS) and angina using the National Health and Nutrition Examination Survey database over a 12-year period.

Methods  Self-reported smoking status and cotinine levels were used to identify exposure groups (smokers, nonsmokers, and secondhand smokers), and medical history of angina was also collected via a self-report survey. The association between exposure to SHS and angina was analyzed using odd ratios with 95% confidence intervals calculated using two logistic regression models.

Results  The study found that when aggregating data from all 12 years, secondhand smokers are 42.9% significantly more likely to report having experienced angina, while smokers were 97.7% significantly more likely to report having angina compared with nonsmokers.

Conclusions  This study is the first of its kind to examine data from a national database over a 12-year period to determine an association between SHS and angina outcomes, thus highlighting the importance of reducing SHS exposure to improve cardiovascular health.

Secondhand Smoke Exposure is Associated with Prevalent Heart Failure: Longitudinal Examination of the National Health and Nutrition Examination Survey

INTRODUCTION

Serum cotinine is a sensitive and specific biomarker for tobacco exposure including second-hand smoke exposure (SHS). We sought to examine whether SHS is associated with heart failure (HF) among non-hospitalized adults.

METHODS

This analysis included 11 219 non-smokers (age 48.4 ± 20.5 years, 55.9% women, 70.5% whites) from the United States Third National Health and Nutrition Examination (NHANES) years 1988-1994. SHS was defined as serum cotinine ≥1 ng/mL. To assess dose-response, cut-points of serum cotinine ≥3 ng/mL and ≥6 ng/mL were used. Multivariable logistic regression was used to examine the association between SHS and HF. The consistency of this association was tested among subgroups stratified by race, gender, and comorbidities. NHANES years 2003-2006 were examined for longitudinal comparison.

RESULTS

18.9% (n = 2125) of participants had SHS exposure while 3.7% (n = 416) had HF. After adjusting for covariates, SHS was associated with a 35% increased odds of HF with a dose-response relationship between levels of serum cotinine and HF. This association was stronger in males than females (interaction p-value = 0.03) and those with a history of CVD versus those without (interaction p-value < 0.001). This association persisted in the NHANES 2003-2006 analysis.

CONCLUSION

There is a dose-response relationship between SHS and HF with possible effect modification by gender and prior CVD. This is a novel finding that underscores the harmful effects of passive smoking on the cardiovascular system and highlights the needs for further prohibition of smoking in public areas and a personalized risk assessment among high-risk groups, especially in regions with less-stringent public health policies.

IMPLICATIONS

This study showed a novel association between secondhand smoke exposure and prevalent heart failure among non-smokers, adding to the list of harmful cardiovascular manifestations of secondhand smoke exposure. This was more apparent in men and those with a prior history of cardiovascular disease. Heart failure is a debilitating disease process, so this finding has important policy implications in low-income countries and poor communities with less-stringent health policies because they are known to have the highest levels of exposure. Smoke-free policies targeting these regions would thus yield substantial public health benefits.