Smoking effect on ischemic heart disease in young patients

Prevention of cardiovascular disease in young adults: Focus on gender differences. A collaborative review from the EAS Young Fellows

A steady rise in cardiovascular morbidity and mortality has been observed in young adults within the last decades. This trend corresponds to an increasing prevalence of traditional cardiovascular risk factors such as obesity and diabetes mellitus type 2 among young adults living in developed countries. Moreover, age-specific risk factors, such as substance abuse, contraceptive medication, and pregnancy-related diseases also correlate with an increased incidence of cardiovascular diseases. In this review, we discuss the available data for young adults on the epidemiology and the rationale for the causality of traditional and newly emerging risk factors of atherosclerotic cardiovascular diseases. We focus on gender-related differences in the exposure to these risk factors, investigate the recent data regarding screening and risk stratification in the young adult population, and describe the current state of the art on lifestyle and therapeutic intervention strategies in the primary prevention setting.

Substance Use Disorders (SUDs) and Risk of Cardiovascular Disease (CVD) and Cerebrovascular Disease (CeVD): Analysis of the Nationwide Inpatient Sample (NIS) Database

BACKGROUND

 Substance use continues to be on the rise in the United States and has been linked to new onset cardiovascular diseases (CVDs) and cerebrovascular disorders (CeVDs). We aimed to study the association between the types of substance use disorders (SUDs) with specific subtypes of CVDs and CeVDs among hospitalized patients using the National Inpatient Sample (NIS) Database.

METHODS

 A retrospective study of the NIS database (2016-2017) using the ICD-10-CM codes was performed. The hospitalizations with a secondary diagnosis of SUDs were identified. Weighted univariate analysis using the Chi-square test and multivariate survey logistic regression analysis was performed to evaluate for the incidence, prevalence, and odds of association between vascular events and SUDs.

RESULTS

 There were a total of 58,259,589 hospitalizations, out of which 21.42% had SUDs. SUDs were more common in the younger age group of 18-50, males, and the lower median household income group. We found a significant association of acute ischemic stroke (AIS) with amphetamine dependence (adjusted odds ratio, aOR 1.23, 95% confidence interval, CI 1.14-1.33), cocaine-related disorders (1.17, 1.12-1.23), and nicotine dependence (1.42, 1.40-1.43). There was a significant association between intracerebral hemorrhage with amphetamine dependence (2.58, 2.26-2.93), cocaine-related disorders (1.62, 1.46-1.79), and alcohol-related disorders (1.35, 1.01-1.82). The association of subarachnoid hemorrhage (SAH) was noted to be higher with amphetamine dependence (1.82, 1.48-2.24) and nicotine dependence (1.47, 1.39-1.55). The patients with nicotine dependence had greater odds of having a myocardial infarction (1.85, 1.83-1.87), those with cocaine-related disorders had higher odds of having angina pectoris (2.21, 1.86-2.62), and patients with alcohol-related disorders had higher odds of developing atrial fibrillation (1.14, 1.11-1.17) in comparison to non-SUDs.

CONCLUSION

 Our study demonstrates the variability of CVD and CeVD in patients hospitalized for SUD. Findings from our study may help promote increased awareness and early management of these events. Further studies are needed to evaluate the specific effects of frequency and dose on the incidence and prevalence of CVD and CeVD in patients with SUD.

The Risk Factors of Acute Coronary Syndrome in Young Women: A Systematic Review and Meta-Analysis

BACKGROUND

Acute coronary syndrome (ACS) has been one of the leading causes of mortality in the world. Despite common understanding regarding ACS as an older population's or man's disease, the number of young women affected by this condition is increasing. Many studies have assessed the risk factors of ACS, but only a few studies focused on this subpopulation. Therefore, this systematic review and meta-analysis aim to evaluate the risk factors predisposing to ACS in the young women population.

METHODS

Nine online databases were screened from the date of inception to September 2021, where the acquired studies were evaluated using the PRISMA statement. The inclusion criteria were a case control study with women age cut-off of <50 years. The risk factors of acute coronary syndrome were analyzed using a random-effect model, expressed as summary statistics of odds ratio (OR) for categorical variable and standard mean difference (SMD) for continuous data with normal distribution, with 95% confidence interval (CI). Quality assessment was conducted using the STROBE statement.

RESULTS

Seven studies with the total of 7042 patients met the inclusion criteria of this metaanalysis. Diabetes mellitus, high BMI, obesity, hypercholestrolemia, hypertension, smoking, and family history significantly increased acute coronary syndrome risk in young women. Other risks such as heavy alcohol consumption, oral contraceptive use, and postmenopausal state were associated with higher risk of ACS.

CONCLUSION

The independent risk factors which are strongly related to ACS in young women were diabetes mellitus, hypertension, and hypercholesterolemia with odd ratios of 6.21, 5.32, and 4.07. Other risk factors which may be associated with an increased risk of ACS in young women were heavy alcohol consumption, oral contraceptive use, and postmenopausal state. Health promotion and effective intervention on this specific population regarding these risk factors can decrease young female cardiovascular morbidity and mortality as well as improved quality of life of women.

Health effects associated with smoking: a Burden of Proof study

As a leading behavioral risk factor for numerous health outcomes, smoking is a major ongoing public health challenge. Although evidence on the health effects of smoking has been widely reported, few attempts have evaluated the dose-response relationship between smoking and a diverse range of health outcomes systematically and comprehensively. In the present study, we re-estimated the dose-response relationships between current smoking and 36 health outcomes by conducting systematic reviews up to 31 May 2022, employing a meta-analytic method that incorporates between-study heterogeneity into estimates of uncertainty. Among the 36 selected outcomes, 8 had strong-to-very-strong evidence of an association with smoking, 21 had weak-to-moderate evidence of association and 7 had no evidence of association. By overcoming many of the limitations of traditional meta-analyses, our approach provides comprehensive, up-to-date and easy-to-use estimates of the evidence on the health effects of smoking. These estimates provide important information for tobacco control advocates, policy makers, researchers, physicians, smokers and the public.

Risk factors profile of young and older patients with myocardial infarction

Myocardial infarction (MI) among young adults (<45 years) represents a considerable proportion of the total heart attack incidents. The underlying pathophysiologic characteristics, atherosclerotic plaque features, and risk factors profile differ between young and older patients with MI. This review article discusses the main differences between the younger and elderly MI patients as well as the different pathogenic mechanisms underlying the development of MI in the younger. Young patients with MI often have eccentric atherosclerotic plaques with inflammatory features but fewer lesions, and are more likely to be smokers, obese, and have poor lifestyle, such as inactivity and alcohol intake. Compared to older MI patients, younger are more likely to be men, have familial-combined hyperlipidaemia and increased levels of lipoprotein-a. In addition, MI in younger patients may be related to use of cannabis, cocaine use, and androgenic anabolic steroids. Genomic differences especially in the pathways of coagulation and lipid metabolism have also been identified between young and older patients with MI. Better understanding of the risk factors and the anatomic and pathophysiologic processes in young adults can improve MI prevention and treatment strategies in this patient group. Awareness could help identify young subjects at increased risk and guide primary prevention strategies. Additional studies focusing on gene pathways related to lipid metabolism, inflammation, and coagulation are needed.

Polymorphisms of LPA gene, rs1801693 and rs7765781, are not associated with premature myocardial infarction in the Iranian population

BACKGROUND

Myocardial infarction (MI) is one of the leading causes of mortality globally. Although it is most prevalent in the elderly, it may occur in young adults (men ≤ 55 years or women ≤ 65 years) as premature MI (PMI). As awareness of genetic risks may lead to effective prevention of PMI, we aim to investigate the association of two susceptible single nucleotide polymorphisms (SNPs) in the LPA gene with PMI in the Iranian population, rs1801693 and rs7765781, identified in previous genome-wide association studies (GWAS).

METHODS

A total number of 85 patients with PMI and 85 healthy controls were recruited from December 2015 to March 2016 from Isfahan, Iran. Peripheral blood samples were collected from all individuals. Deoxyribonucleic acid (DNA) was extracted and genotyped at rs1181693 and rs7765781 polymorphisms, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Results were statistically analyzed to find any possible association of the two polymorphisms with PMI by SPSS software and P-values less than 0.05 were considered to be statistically significant.

RESULTS

Statistical analysis displayed no significant difference between rs1801693 (P = 0.815)/rs7765781 (P = 0.746) alleles in patients with PMI and healthy control subjects.

CONCLUSION

There is no meaningful association between rs1801693/rs7765781 and PMI incidence in the Iranian population.

Coronary artery disease in the young in the US population-based cohort

BACKGROUND

Although most prevalent in the elderly, coronary artery disease (CAD) also affects younger adults. However, CAD in young adults is not as well characterized.

OBJECTIVE

To explore factors associated with CAD in young patients.

METHODS

We investigated the prevalence and baseline characteristics of young patients with CAD using the National Health and Nutrition Examination Survey (NHANES) survey between 1999 and 2016. The primary outcome was a reported history of CAD at age <55 years old, defined based on the subject's response to survey questions 'Have you ever been told by a physician that you had coronary artery disease?' and 'How old were you when were told you had coronary heart disease?'. Multivariable logistic regression models were used to assess factors associated with CAD in young patients.

RESULTS

Of 42,038 NHANES participants, 707 (1.7%) reported CAD at young age. Young patients with CAD were more likely to be male, non-whites, cigarette smokers, recreational drug users, had a family history of CAD, compared to young patients without CAD (all p-values <0.05). In multivariable logistic regression models, diabetes (OR: 3.94; 95% CI: 1.32-11.8; P=0.01), cigarette smoking (OR: 2.86; 95% CI: 1.52-5.53; P=0.001), alcohol consumption (OR: 1.17; 95% CI: 1.04-1.35; P=0.01) and cocaine use (OR: 4.48; 95% CI: 1.33-15.1; P=0.01) were independently associated with CAD in young patients.

CONCLUSION

CAD in young patients may be influenced by lifestyle factors such as alcohol consumption or cocaine use, as well as conventional risk factors such as smoking or diabetes.

Nicotine induces cardiac toxicity through blocking mitophagic clearance in young adult rat

Since an outbreak of vaping-related deaths in the US has been reported as a public health crisis, the cardiovascular safety of nicotine nowadays receives increasing attention due to use of tobacco cigarette alternatives, such as electronic cigarettes. However, whether and how nicotine contributes to cardiac detrimental effects are in great controversy, especially less understood in young adult population. We report that chronic nicotine exposure, a major component of Electronic cigarettes, resulted in directly inhibited cardiomyocytes viability, increased cardiac fibrosis, and markedly suppressed cardiac function compared with sham. Gene array combined with bioinformatics analysis identified cardiac apoptosis and mitophagy were the key signals responsible for nicotine induced cardiac detrimental effect. Mechanistically, nicotine exposure markedly increased cleaved Caspase 3 and cleaved Caspase 9 indicating the involvement of intrinsic apoptotic pathway (mitochondrial cell death pathway). Meanwhile, nicotine-induced ROS outbreak promoted lysomal alkalization, furthermore blocked mitophagic degradation, thereby disrupted mitophagic flux promoted mitochondrial cell death cascade. Taken together, these findings indicate that nicotine confers cardiotoxicity via ROS-induced mitophagic flux blockage and provide the first demonstration of a causative link between nicotine and cardiac toxicity in young adult rat which may suggest nicotine induces cardiomyocytes impairment leading to cardiotoxicity in young adult population.

The risk and burden of smoking related heart disease mortality among young people in the United States

PURPOSE

Although cigarette smoking remains the most common risk factor for heart disease among the young, few studies have explored the relationship of smoking with heart disease mortality risk among young people. This prospective study assesses the risk and burden of all heart disease (HD) and coronary heart disease (CHD) mortality associated with smoking among younger adults from a nationally representative sample of the United States.

METHOD

National Health Interview Survey respondents' data from 1997-2004 were linked to their death records through 2006. The analyses were restricted to individuals 18 to 44 years of age during follow up (n = 121,284). Cox proportional hazard ratios (HR) were estimated with adjustment for sample weights and design effects. Attributable fractions (AF) of smoking were calculated.

RESULTS

After controlling for age, race, body mass index, history of hypertension and diabetes, and leisure time physical activity, current smoking related CHD mortality HR was 14.6 [95 % confidence interval or CI, 3.3-64.9] for females and 3.6 [95 % CI, 1.2-10.4] for males. The HR for all HD mortality was 3.1 [95 % CI, 1.3-7.6] for females and 2.4 [95 % CI, 1.2-4.7] for males. The AF of smoking for CHD deaths for female and male were 0.58 and 0.54 respectively. The AF of all HD mortality was 0.31 for male and 0.32 for female. The mean estimates of all HD deaths attributable to smoking during 1997-2006 among this age group were 52,214, of which 45,147 were CHD deaths.

CONCLUSION

Even after adjustment for multiple risk factors and without addressing passive smoking, our result showed a strong relationship between smoking and HD and CHD mortality among young adults that is likely causal.

Acute coronary syndromes in young women - the scale of the problem and the associated risks

Diseases of the cardiovascular system mainly affect elderly patients, but they are increasingly often encountered in young individuals. It is estimated that 1 in 20 patients with ischemic heart disease is under the age of 45 years. Only 20% of them are women. According to the PL-ACS register, cases of acute coronary syndromes in young women represent 0.6% of all acute coronary syndrome cases.

The most common etiology is atherosclerosis (80%). Other causes include dissections and spasms of the coronary arteries as well as clotting disorders. Smoking tobacco is the most important risk factor, followed by hypertension, hyperlipidemia, and diabetes. The long-term prognosis is usually favorable, but it deteriorates significantly in the event of complications.

The literature on this subject is not extensive. Most data come from non-randomized studies of young patients conducted regardless of sex.

The purpose of this paper is to present the problem posed by acute coronary syndromes in young women.

Comparison of clinical features and outcomes of patients with acute myocardial infarction younger than 35 years with those older than 65 years

PURPOSE

The objective of this study was to analyze the clinical characteristics of patients younger than 35 years with acute myocardial infarction (AMI).

METHODS

A total of 117 patients younger than 35 years with AMI admitted to the hospital during the recent 10 years were chosen, and 355 patients older than 65 years with AMI served as a control group. The case history, clinical data, coronary angiography and prognosis of the patients were analyzed and compared.

RESULTS

Among the younger patients with AMI, men (96.6%) and those smoking cigarettes (66.7%) account for the majority. ST-segment elevation (69.2%) and anterior wall infarction (43.6%) were more prevalent in the younger patients than in the older patients. Compared with the older patients, the younger patients had a higher level of low-density lipoprotein cholesterol (2.93 ± 1.48 versus 2.35 ± 1.21, P = 0.0428) and higher left ventricular ejection fraction (59.82 ± 10.86 versus 48.31 ± 12.48, P = 0.0396). Coronary angiography data showed that most of the younger patients were characteristic of having single-vessel lesion (66.7%), left anterior descending artery lesion (69.3%) and coronary artery spasm more than the older patients (6.8% versus 0.56%, P = 0.0001). In addition, the in-hospital mortality, and the prognosis after 1 and 12 months in the younger patients were comparatively better.

CONCLUSIONS

The main risk factors for young adults aged <35 years with AMI include cigarette smoking, hyperlipidemia and family history of coronary artery disease, and smoking cessation and lifestyle improvement are important considerations for the prevention of this disease in this population.