Presentation, management and mortality after a first MI in people with and without asthma: A study using UK MINAP data

Understanding the Link Between Adult Asthma and Coronary Artery Disease: A Narrative Review

Asthma is a common pathology worldwide that occurs due to chronic inflammation of the respiratory airways. Persistent pulmonary inflammation leads to low-grade systemic inflammation, influencing blood vessels and triggering coronary artery disease (CAD) events. This review's objectives include discussing the susceptible population for CAD, the mechanism underlying CAD creation in asthma patients, the characteristics of asthma, and the influence of anti-asthmatic medications on CAD development. Adult-onset asthma is strongly linked to CAD and stroke. Future research may shed light on these disparities. Atherosclerosis and asthma are linked through both intrinsic and extrinsic pathways, with inflammation being the intrinsic pathway and hypoxia and tachyarrhythmia being the extrinsic pathways. The most probable mechanisms for increased coronary vasospastic angina (CVsA) incidence in asthmatic patients are vascular smooth muscle cell hypercontraction and endothelial dysfunction. Studies have shown a dose-response relationship between asthma control and myocardial infarction (MI) risk, with uncontrolled asthma at the highest risk. Impairment of ventilatory function is a distinct risk factor for lethal MI and cardiovascular death (CVD). The use of beta-2-agonists and chronic oral glucocorticoid therapy in severe asthmatics has been linked to increasing the risk for CAD. However, some studies have shown that the risk of MI among patients with active asthma is not related to the use of asthma medications. Further research is needed to determine the involvement of adult asthma features and their treatments in the development of CAD.

The safety of cardioselective β1-blockers in asthma: literature review and search of global pharmacovigilance safety reports

INTRODUCTION

Beta-blockers are key in the management of cardiovascular diseases but blocking airway β2-receptors can cause severe and sometimes fatal bronchoconstriction in people with asthma. Although cardioselective β1-blockers may be safer than non-selective β-blockers, they remain relatively contraindicated and under-prescribed. We review the evidence of the risk associated with cardioselective β1-blocker use in asthma.

METHODS

We searched "asthma" AND "beta-blocker" in PubMed and EmbaseOvid from start to May 2020. The World Health Organization (WHO) global database of individual case safety reports (VigiBase) was searched for reports of fatal asthma or bronchospasm and listed cardioselective β1-blocker use (accessed February 2020). Reports were examined for evidence of pre-existing asthma.

RESULTS

PubMed and EmbaseOvid searches identified 304 and 327 publications, respectively. No published reports of severe or fatal asthma associated with cardioselective β1-blockers were found. Three large observational studies reported no increase in asthma exacerbations with cardioselective β1-blocker treatment. The VigiBase search identified five reports of fatalities in patients with pre-existing asthma and reporting asthma or bronchospasm during cardioselective β1-blocker use. Four of these deaths were unrelated to cardioselective β1-blocker use. The circumstances of the fifth death were unclear.

CONCLUSIONS

There were no published reports of cardioselective β1-blockers causing asthma death. Observational data suggest that cardioselective β1-blocker use is not associated with increased asthma exacerbations. We found only one report of an asthma death potentially caused by cardioselective β1-blockers in a patient with asthma in a search of VigiBase. The reluctance to use cardioselective β1-blockers in people with asthma is not supported by this evidence.

The impact of regular bisoprolol on the response to salbutamol in asthma: A double-blind randomized placebo-controlled crossover trial

BACKGROUND AND OBJECTIVE

Non-selective beta-blockers impair the bronchodilator response to beta₂ -agonists. Cardio-selective beta₁ -blockers are less likely to cause this effect, yet they remain relatively contraindicated in asthma. We investigated whether the response to salbutamol is impaired during cardio-selective beta₁ -blocker treatment in people with asthma.

METHODS

A random-order, double-blind, placebo-controlled, non-inferiority, crossover study was conducted comparing up to 5 mg bisoprolol daily for 2 weeks with matching placebo, with an open-label extension of up to 10 mg bisoprolol daily. After each treatment period, mannitol was inhaled to induce bronchoconstriction with a 15% fall in forced expiratory volume in 1 s (FEV₁ ). Immediately after mannitol challenge, salbutamol (100, 100 and 200 μg) was administered via spacer at 5-min intervals with repeated FEV₁ measures. The FEV₁ recovery with salbutamol was measured as an area under recovery curve (AUC). Based on earlier research, a clinically relevant non-inferiority limit of a 30% reduction in the AUC was set.

RESULTS

A total of 19 adults with mild asthma and positive inhaled mannitol challenge completed the study. Adjusting for the FEV₁ fall induced by mannitol and treatment sequence, the mean AUC response to salbutamol after bisoprolol was 5% lower than after placebo, with a one-sided 95% confidence interval (CI) of 26% lower. Thirteen participants completed the open-label extension up to 10 mg bisoprolol daily with mean AUC 11% higher after bisoprolol with a 95% CI of 5% lower.

CONCLUSION

The bronchodilator response to rescue salbutamol after mannitol-induced bronchoconstriction is non-inferior during regular treatment with the cardio-selective beta₁ -blocker, bisoprolol, compared to placebo.

CLINICAL TRIAL REGISTRATION

ACTRN12618000306213 at https://www.anzctr.org.au.

Statistics on mortality following acute myocardial infarction in 842 897 Europeans

AIMS

To compare ST-segment elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI) mortality between Sweden and the UK, adjusting for background population rates of expected death, case mix, and treatments.

METHODS AND RESULTS

National data were collected from hospitals in Sweden [n = 73 hospitals, 180 368 patients, Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies (SWEDEHEART)] and the UK [n = 247, 662 529 patients, Myocardial Ischaemia National Audit Project (MINAP)] between 2003 and 2013. There were lower rates of revascularization [STEMI (43.8% vs. 74.9%); NSTEMI (27.5% vs. 43.6%)] and pharmacotherapies at time of hospital discharge including [aspirin (82.9% vs. 90.2%) and (79.9% vs. 88.0%), β-blockers (73.4% vs. 86.4%) and (65.3% vs. 85.1%)] in the UK compared with Sweden, respectively. Standardized net probability of death (NPD) between admission and 1 month was higher in the UK for STEMI [8.0 (95% confidence interval 7.4-8.5) vs. 6.7 (6.5-6.9)] and NSTEMI [6.8 (6.4-7.2) vs. 4.9 (4.7-5.0)]. Between 6 months and 1 year and more than 1 year, NPD remained higher in the UK for NSTEMI [2.9 (2.5-3.3) vs. 2.3 (2.2-2.5)] and [21.4 (20.0-22.8) vs. 18.3 (17.6-19.0)], but was similar for STEMI [0.7 (0.4-1.0) vs. 0.9 (0.7-1.0)] and [8.4 (6.7-10.1) vs. 8.3 (7.5-9.1)].

CONCLUSION

Short-term mortality following STEMI and NSTEMI was higher in the UK compared with Sweden. Mid- and longer-term mortality remained higher in the UK for NSTEMI but was similar for STEMI. Differences in mortality may be due to differential use of guideline-indicated treatments.