Assessment of serum cotinine in patients with chronic heart failure: self-reported versus objective smoking behaviour

Assessing tobacco use in Swedish young adults from self-report and urinary cotinine: a validation study using the BAMSE birth cohort

OBJECTIVES

Studies on health effects of tobacco often rely on self-reported exposure data, which is subjective and can lead to misclassification. The aim of this study was to describe the prevalence of cigarette smoking, snus and e-cigarette use, as well as to validate self-reported tobacco use among young adults in Sweden.

METHOD

Participants of a population-based Swedish cohort (n=3052), aged 22-25 years, assessed their tobacco use in a web questionnaire. Urinary cotinine was analysed in a subsample of the study population (n=998). The agreement between self-reported tobacco use and urinary cotinine was assessed using Cohen's Kappa coefficient (κ) at a cut-off level of 50 ng/mL.

RESULTS

Patterns of tobacco use differed between men and women. Among men, 20.0% reported daily snus use, 5.8% daily cigarette smoking and 5.6% any e-cigarette use. In contrast, 3.2% of the women reported daily snus use, 9.0% daily cigarette smoking and 2.4% any e-cigarette use. Among the tobacco use categories, daily snus users had the highest levels of cotinine. Of reported non-tobacco users, 3.5% had cotinine levels above the cut-off, compared with 68.0% among both occasional cigarette smokers and snus users, 67.5% among all e-cigarette users and 94.7% and 97.8% among daily cigarette smokers and snus users, respectively. Agreement between self-reported tobacco use and urinary cotinine was classified as strong for daily use of cigarettes (κ=0.824) and snus (κ=0.861), while moderate to weak for occasional smoking (κ=0.618), occasional snus use (κ=0.573) and any e-cigarette use (κ=0.576).

CONCLUSIONS

We found high validity of self-reported tobacco use in our study population, particularly for daily tobacco use. Further, we found that daily snus users were exposed to high levels of cotinine. Together with previous findings, our results indicate good validity of self-reported tobacco use among young adults.

Cardiac cachexia among patients with chronic heart failure: A systematic review

INTRODUCTION

Despitecardiac cachexia being a prevalent health problem among heart failure (HF) patients, it has been given little attention by nursing researchers. Therefore, this study aims to conduct a systematic review that investigates cardiac cachexia among patients with HF.

METHODOLOGY

A systematic review will be performed according to the PRISMA guidelines to assess the findings of twelve selected studies which meet the inclusion criteria of the systematic review research. The selected articles were published between 2000 and 2020 across three databases: PubMed, CINAHL, and MEDLINE.

RESULTS

In comparison to cancer cachexia, cardiac cachexia has been insufficiently studied and is poorly understood. No definitive diagnostic method for cardiac cachexia has been identified in the literature. Age, smoking, and hypertension have been reported to be risk factors for cardiac cachexia. Cardiac cachexia has been significantly associated with lethal structural changes in the heart and has been measured using anthropometric measures and laboratory biomarkers. A combination of pharmacological and nonpharmacological treatments has been effectively implemented to manage cardiac cachexia.

CONCLUSION

A focused multidisciplinary approachthat takes culture into consideration is required to set a variety of assessment and interventional strategies for the early detection and proper management of cardiac cachexia.

Relation Between Cigarette Smoking and Heart Failure (from the Multiethnic Study of Atherosclerosis)

We studied the association between cigarette smoking and incident heart failure (HF) in a racially diverse US cohort. We included 6,792 participants from the Multi-Ethnic Study of Atherosclerosis with information on cigarette smoking at baseline, characterized by status, intensity, burden, and time since quitting. Adjudicated outcomes included total incident HF cases and HF stratified by ejection fraction (EF) into HF with reduced EF (HFrEF; EF ≤ 40%) and preserved EF (HFpEF; EF ≥ 50%). We used Cox proportional hazards models adjusted for traditional cardiovascular risk factors and accounted for competing risk of each HF type. Mean age was 62 ± 10 years; 53% were women, 61% were nonwhite, and 13% were current smokers. A total of 279 incident HF cases occurred over a median follow-up of 12.2 years. The incidence rates of HFrEF and HFpEF were 2.2 and 1.9 cases per 1000 person-years, respectively. Current smoking was associated with higher risk of HF compared with never smoking (hazard ratio [HR], 2.05; 95% confidence interval [CI], 1.36 to 3.09); this was similar for HFrEF (HR, 2.58; 95% CI, 1.27 to 5.25) and HFpEF (HR, 2.51; 95% CI, 1.15 to 5.49). Former smoking was not significantly associated with HF (HR, 1.17; 95% CI, 0.88 to 1.56). Smoking intensity, burden, and time since quitting did not provide additional information for HF risk after accounting for smoking status.

Deception in clinical trials and its impact on recruitment and adherence of study participants

Deceptive practices by participants in clinical research are prevalent. It has been shown that as high as 75% of participants withheld information to avoid exclusion from studies. Self-reported adherence has been found to be largely inaccurate. Overcoming deception is a critical issue, since the safety of study participants, the integrity of research data and research resources are at risk. In this review article, we examine deception from the perspective of investigators conducting clinical trials; we describe the types (concealment, fabrication, drug holidays and collusion), prevalence, risks, and predictors of deception, and propose an approach to reduce the impact of deception, especially on adherence, in clinical trials.

Differential effect of cigarette smoke exposure on exhaled nitric oxide and blood eosinophils in healthy and asthmatic individuals

BACKGROUND

Tobacco smoking affects both the fraction of exhaled nitric oxide (FeNO) and blood eosinophil (B-Eos) count, two clinically useful biomarkers in respiratory disease that represent local and systemic type-2 inflammation, respectively.

OBJECTIVE

We aimed to study the influence of objectively measured smoke exposure on FeNO and B-Eos in a large population of subjects with and without asthma.

METHODS

We utilized the US National Health and Nutrition Examination Surveys 2007-2012 and included 10 669 subjects aged 6-80 years: 9869 controls and 800 asthmatics. Controls were defined as having no respiratory disease, no hay fever in the past year, and B-Eos count ≤0.3 × 10⁹ l^-1. Asthma was defined as self-reported current asthma and at least one episode of wheezing or an asthma attack in the past year, but no emphysema or chronic bronchitis. Tobacco use was collected via questionnaires and serum cotinine was measured with mass spectrometry.

RESULTS

Increasing cotinine levels were associated with a progressive reduction in FeNO in both controls and asthmatics. FeNO remained significantly higher in asthmatics than controls except in the highest cotinine decile, equivalent to an average reported consumption of 13 cigarettes/day. B-Eos count increased with cotinine in controls, but was unchanging in asthmatics. Interestingly, B-Eos count was significantly higher in presently non-exposed (cotinine below detection limit) former smokers than never smokers.

CONCLUSION

Smoke exposure decreases FeNO and increases B-Eos count. These effects should be considered in the development of normalized values and their interpretation in clinical practice. The persistence of elevated B-Eos in former smokers warrants further studies.

Serum Cotinine Does Not Predict Neutralizing Antibodies Against Interferon Beta in an Austrian MS Cohort

Previous epidemiologic studies showed an increased risk of neutralizing antibody (NAb) development against Interferon beta in multiple sclerosis patients who smoke. Cotinine is an easily detectable metabolite of nicotine and, therefore, can be used as an objective surrogate marker for smoking status. We measured cotinine levels in NAb-positive and NAb-negative patients to find a potential association of nicotine consumption and NAb development. Cotinine was measured in 37 patients with known smoking status and in 123 patients with unknown smoking status, all of whom were routinely tested for NAb. Cotinine was detected by an enzyme-linked immunosorbent assay, inhibition assay. We compared cotinine levels by NAb status and tested for the strength of association between cotinine and NAb status. We found a discrepancy between smoking status stated by patients and status defined by cotinine levels in 7 of 37 patients. In both cohorts, together with and without previously known smoking status (n = 160), we found 34% and 39% smokers, respectively, as defined by cotinine levels in NAb-negative and NAb-positive patients (P = 0.511). In our analysis, smoking was not associated with higher risk of NAb development. Moreover, smoking habits stated by patients do not always correlate with cotinine levels.