Angina pectoris in women: Focus on microvascular disease

Health outcomes and healthcare utilization associated with four undiagnosed chronic conditions: evidence from nationally representative survey data in Sri Lanka

Background

Low awareness of chronic conditions raises the risk of poorer health outcomes and may result in healthcare utilization and spending in response to symptoms of undiagnosed conditions. Little evidence exists, particularly from lower-middle-income countries, on the health and healthcare use of undiagnosed people with an indication of a condition. This study aimed to compare health (physical, mental, and health-related quality of life (HRQoL)) and healthcare (inpatient and outpatient visits and out-of-pocket (OOP) medical spending) outcomes of undiagnosed Sri Lankans with an indication of coronary heart disease (CHD), hypertension, diabetes, and depression with the outcomes of their compatriots who were diagnosed or had no indication of these conditions.

Methods

This study used a nationally representative survey of Sri Lankan adults to identify people with an indication of CHD, hypertension, diabetes, or depression, and ascertain if they were diagnosed. Outcomes were self-reported measures of physical and mental functioning (12-Item Short Form Survey (SF-12)), HRQoL (EQ-5D-5L), inpatient and outpatient visits, and OOP spending. For each condition, we estimated the mean of each outcome for respondents with (a) no indication, (b) an indication without diagnosis, and (c) a diagnosis. We adjusted the group differences in these means for socio-demographic covariates using ordinary least squares (OLS) regression for physical and mental function, Tobit regression for HRQoL, and a generalized linear model (GLM) for healthcare visits and OOP spending.

Results

An indication of each of CHD and depression, which are typically symptomatic, was associated with a lower adjusted mean of physical (CHD -2.65, 95% CI -3.66, -1.63; depression -5.78, 95% CI -6.91, -4.64) and mental functioning (CHD -2.25, 95% CI -3.38, -1.12; depression -6.70, 95% CI -7.97, -5.43) and, for CHD, more annual outpatient visits (2.13, 95% CI 0.81, 3.44) compared with no indication of the respective condition. There were no such differences for indications of hypertension and diabetes, which are often asymptomatic.

Conclusions

Living with undiagnosed CHD and depression was associated with worse health and, for CHD, greater utilization of healthcare. Diagnosis and management of these symptomatic conditions can potentially improve health partly through substitution of effective healthcare for that which primarily responds to symptoms.

Supplementary Information

The online version contains supplementary material available at 10.1186/s44263-024-00075-0.

The Prevalence and Epidemiological Features of Ischaemic Heart Disease in Sri Lanka

Background

There is limited evidence on the prevalence of ischaemic heart disease (IHD) and its association with risk factors and socioeconomic status (SES) in low- and middle-income countries (LMICs). Given the relatively high levels of access to healthcare in Sri Lanka, the association of IHD with SES may be different from that observed in other LMICs.

Objectives

To estimate the prevalence of IHD in Sri Lanka, determine its associated risk factors and its association with SES.

Methods

We analysed data from 6,513 adults aged ≥18 years examined in the 2018/19 Sri Lanka Health and Ageing Study. We used the Rose angina questionnaire to classify participants as having angina (Angina+) and used self-report or medical records to identify participants with a history of IHD (History+). The association of Angina+ and History+ with age, ethnicity, sector of residence, education level, household SES wealth quintile, area SES wealth quintile, hypertension, diabetes, smoking, total cholesterol, cholesterol-to-HDL ratio, waist-to-hip ratio and body mass index were analysed in unadjusted and adjusted models. Additional analyses were performed to investigate sensitivity to correction for missing data and to benchmark estimates against evidence from other studies.

Conclusions

We estimated prevalence of History+ of 3.9% (95% CI 3.3%-4.4%) and Angina+ of 3.0% (95% CI 2.4%-3.5%) in adults aged 18 years and over. The prevalence of Angina+ was higher in women than men (3.9% vs. 1.9%, p < 0.001) whilst prevalence of History+ was lower (3.8% vs. 4.0%, p = 0.8), which may suggest a higher rate of undiagnosed IHD in women. A history of IHD was strongly associated with age, hypertension and diabetes status even after adjusting for sociodemographic factors. Though the prevalence of History+ was higher in the most developed area SES tertile and urban areas, History+ was also associated with less education but not household SES, consistent with patterns emerging from other LMICs.

A proposed tree-based explainable artificial intelligence approach for the prediction of angina pectoris

Cardiovascular diseases (CVDs) are a serious public health issue that affects and is responsible for numerous fatalities and impairments. Ischemic heart disease (IHD) is one of the most prevalent and deadliest types of CVDs and is responsible for 45% of all CVD-related fatalities. IHD occurs when the blood supply to the heart is reduced due to narrowed or blocked arteries, which causes angina pectoris (AP) chest pain. AP is a common symptom of IHD and can indicate a higher risk of heart attack or sudden cardiac death. Therefore, it is important to diagnose and treat AP promptly and effectively. To forecast AP in women, we constructed a novel artificial intelligence (AI) method employing the tree-based algorithm known as an Explainable Boosting Machine (EBM). EBM is a machine learning (ML) technique that combines the interpretability of linear models with the flexibility and accuracy of gradient boosting. We applied EBM to a dataset of 200 female patients, 100 with AP and 100 without AP, and extracted the most relevant features for AP prediction. We then evaluated the performance of EBM against other AI methods, such as Logistic Regression (LR), Categorical Boosting (CatBoost), eXtreme Gradient Boosting (XGBoost), Adaptive Boosting (AdaBoost), and Light Gradient Boosting Machine (LightGBM). We found that EBM was the most accurate and well-balanced technique for forecasting AP, with accuracy (0.925) and Youden's index (0.960). We also looked at the global and local explanations provided by EBM to better understand how each feature affected the prediction and how each patient was classified. Our research showed that EBM is a useful AI method for predicting AP in women and identifying the risk factors related to it. This can help clinicians to provide personalized and evidence-based care for female patients with AP.

Mitochondrial disorder and treatment of ischemic cardiomyopathy: Potential and advantages of Chinese herbal medicine

Mitochondrial dysfunction is the main cause of damage to the pathological mechanism of ischemic cardiomyopathy. In addition, mitochondrial dysfunction can also affect the homeostasis of cardiomyocytes or endothelial cell dysfunction, leading to a vicious cycle of mitochondrial oxidative stress. And mitochondrial dysfunction is also an important pathological basis for ischemic cardiomyopathy and reperfusion injury after myocardial infarction or end-stage coronary heart disease. Therefore, mitochondria can be used as therapeutic targets against myocardial ischemia injury, and the regulation of mitochondrial morphology, function and structure is a key and important way of targeting mitochondrial quality control therapeutic mechanisms. Mitochondrial quality control includes mechanisms such as mitophagy, mitochondrial dynamics (mitochondrial fusion/fission), mitochondrial biosynthesis, and mitochondrial unfolded protein responses. Among them, the increase of mitochondrial fragmentation caused by mitochondrial pathological fission is the initial factor. The protective mitochondrial fusion can strengthen the interaction and synthesis of paired mitochondria and promote mitochondrial biosynthesis. In ischemia or hypoxia, pathological mitochondrial fission can promote the formation of mitochondrial fragments, fragmented mitochondria can lead to damaged mitochondrial DNA production, which can lead to mitochondrial biosynthesis dysfunction, insufficient mitochondrial ATP production, and mitochondrial ROS. Burst growth or loss of mitochondrial membrane potential. This eventually leads to the accumulation of damaged mitochondria. Then, under the leadership of mitophagy, damaged mitochondria can complete the mitochondrial degradation process through mitophagy, and transport the morphologically and structurally damaged mitochondria to lysosomes for degradation. But once the pathological mitochondrial fission increases, the damaged mitochondria increases, which may activate the pathway of cardiomyocyte death. Although laboratory studies have found that a variety of mitochondrial-targeted drugs can reduce myocardial ischemia and protect cardiomyocytes, there are still few drugs that have successfully passed clinical trials. In this review, we describe the role of MQS in ischemia/hypoxia-induced cardiomyocyte physiopathology and elucidate the relevant mechanisms of mitochondrial dysfunction in ischemic cardiomyopathy. In addition, we also further explained the advantages of natural products in improving mitochondrial dysfunction and protecting myocardial cells from the perspective of pharmacological mechanism, and explained its related mechanisms. Potential targeted therapies that can be used to improve MQS under ischemia/hypoxia are discussed, aiming to accelerate the development of cardioprotective drugs targeting mitochondrial dysfunction.

Receptor for advanced glycation end products gene polymorphisms in cardiac syndrome X

Endothelial and microvascular dysfunction serve important roles in the formation and pathogenesis of cardiac syndrome X (CSX). Expression of receptor for advanced glycation end products (RAGE) is suggested to be increased in several conditions, including diabetes, inflammation and vascular diseases. In the present study, RAGE gene polymorphisms in patients with CSX and healthy controls were investigated. A total of 114 patients, diagnosed with CSX using coronary angiography results following complaints of angina and objective ischemia, and 103 healthy controls participated in the study. Whether there was a difference in genotype distributions of RAGE gene -374T/A, -429T/C and Glys82Ser polymorphisms between patients with CSX and healthy controls was investigated. Following DNA isolation from blood samples of the participants, the polymorphic regions were examined by quantitative polymerase chain reaction, and the genotyping results were statistically analyzed. When the genotypic distributions of -374T/A, -429T/C and Gly82Ser polymorphisms were investigated in patients with CSX and healthy controls, no statistically significant differences were identified between the two groups (P>0.05). Likewise, no statistically significant differences were observed in the allelic distributions of all 3 polymorphic regions (P>0.05). To the best of our knowledge, the present study also investigated the association between CSX and RAGE gene polymorphisms for the first time. No statistically significant differences in RAGE gene polymorphisms between the CSX and control groups were observed. We hypothesized that significant results may be obtained by increasing the numbers of patients and healthy controls in future studies.

Late sodium channel blockade improves angina and myocardial perfusion in patients with severe coronary microvascular dysfunction: Women's Ischemia Syndrome Evaluation-Coronary Vascular Dysfunction ancillary study

BACKGROUND

In a prior trial of late sodium channel inhibition (ranolazine) among symptomatic subjects without obstructive coronary artery disease (CAD) and limited myocardial perfusion reserve index (MPRI), we observed no improvement in angina or MPRI, overall. Here we describe the clinical characteristics and myocardial perfusion responses of a pre-defined subgroup who had coronary flow reserve (CFR) assessed invasively.

METHODS

Symptomatic patients without obstructive CAD and limited MPRI in a randomized, double-blind, crossover trial of ranolazine vs. placebo were subjects of this prespecified substudy. Because we had previously observed that adverse outcomes and beneficial treatment responses occurred in those with lower CFR, patients were subgrouped by CFR <2.5 vs ≥2.5. Symptoms were assessed using the Seattle Angina Questionnaire and the SAQ-7, and left-ventricular volume and MPRI were assessed by magnetic resonance imaging (MRI). Coronary angiograms, CFR, and MRI data were analyzed by core labs masked to treatment and patient characteristics.

RESULTS

During qualifying coronary angiography, 81 patients (mean age 55 years, 98% women) had invasively determined CFR 2.69 ± 0.65 (mean ± SD; range 1.4-5.5); 43% (n = 35) had CFR <2.5. Demographic and symptomatic findings did not differ comparing CFR subgroups. Those with low CFR had improved angina (p = 0.04) and midventricular MPRI (p = 0.03) with ranolazine vs placebo. Among patients with low CFR, reduced left-ventricular end-diastolic volume predicted a beneficial angina response.

CONCLUSIONS

Symptomatic patients with CFR <2.5 and no obstructive CAD had improved angina and myocardial perfusion with ranolazine, supporting the hypothesis that the late sodium channel is important in management of coronary microvascular dysfunction.

TRIAL REGISTRATION

clinicaltrials.gov Identifier NCT01342029.

Sta Ble Angina: Pe Rcept Ion of Nee Ds, Quality of Life and Mana Gem Ent of Patients (BRIDGE Study)-A Multinational European Physician Survey

Stable angina (SA) is a chronic condition reducing physical activity and quality of life (QoL). Physicians treating patients with SA in Italy, Germany, Spain, and United Kingdom completed a web-based survey. The objective was to assess physician perceptions of patient needs, the impact of SA on QoL, and evaluate SA management. Overall, 659 physicians (cardiologists and general practitioners) entered data from 1965 eligible patients. The perceived importance of everyday activities for patients with a recent diagnosis (≤2 years) was higher than for patients with a longer diagnosis (>2 years), while severity of limitations for those activities were rated similarly for both groups. Gender-based analyses revealed that physicians documented more severe SA, more symptoms and more angina attacks in women, yet they rated the patients' condition as similar for both sexes. Women also received less medical and interventional treatment. Patients who have previously had a percutaneous coronary intervention (PCI) had more severe SA, despite more intense medical treatment, than patients with no previous PCI. In conclusion, severity, symptoms, and impact of SA on health status and everyday life activities vary by duration of disease, gender, and previous PCI. However, physicians do not seem to attach appropriate importance to these differences.

Investigation of MTHFR gene C677T polymorphism in cardiac syndrome X patients

BACKGROUND

Definition of Cardiac Syndrome X (CSX) refers to groups of patients with positive exercise stress test and normal epicardial coronary arteries on coronary angiography accompanied by chest pain. Although the etiology of CSX is not completely understood, there is a common consensus that its pathophysiology may be associated with endothelial dysfunction resulting in impaired coronary flow. Some polymorphisms observed on the MTHFR gene cause inactivation of the MTHFR enzyme, leading to hyperhomocysteinemia and homocysteinuria, which are prominent risk factors of cardiovascular and cerebrovascular diseases. It was aimed to explain the association of the endothelial dysfunction, which is thought to play a role in the pathophysiology of CSX, with C677T polymorphism on MTHFR gene based on genetic basis.

METHODS

A total of 176 CSX patients and 196 healthy subjects with similar age and clinical features were compared in terms of C677T polymorphism of the MTHFR gene.

RESULTS AND CONCLUSION

There was no significant difference in terms of MTHFR gene C677T polymorphism between CSX patients and controls. When genotypic distribution was compared based on gender in both patients and controls, no significant difference was found between male and female subjects (P>.05). As fasting blood sugar and urea values were significantly higher, alanine aminotransferase and gamma-glutamyl transferase levels were significantly lower in the patients than the controls (P<.05). Described family story of the patients was significantly higher than the controls (P<.05). These suggest that homocysteine metabolism in CSX is not directly related to the endothelial dysfunction and thus the effect on the microvascular circulation.

The Challenges of Prevention, Diagnosis and Treatment of Ischemic Heart Disease in Women

Increasing evidence suggests that there are significant differences in the presentation, diagnosis and treatment of ischemic heart disease in women compared to men. Women often present with atypical symptoms, and this, in association with a consistent underestimation of their risk for ischemic heart disease, leads to underdiagnosis and undertreatment in women. Cardiovascular risk factors unique to women have only recently been recognized, and moreover, traditional risk factors have recently been shown to have greater impacts on women. Consequently, women suffer more disability and poorer clinical outcomes, with higher cardiovascular morbidity and mortality. These discrepancies may in part be secondary to the higher prevalence of nonobstructive coronary artery disease in women with persistent chest pain symptoms as compared to men when evaluated invasively. Focused diagnostic and therapeutic strategies unique to women are thus needed, but unfortunately, such sex-specific guidelines do not yet exist, largely due to lack of awareness, both on the part of providers and patients, as well as a paucity of evidence-based research specific to women. Although underutilized in women, diagnostic modalities, including functional and anatomic cardiac tests as well as physiologic assessments of endothelial and microvascular function, are useful for establishing the diagnosis and prognosis of suspected ischemic heart disease in women. This review discusses the current challenges of prevention, diagnosis and treatment of ischemic heart disease in women.

Gender comparisons in non-acute cardiac symptom recognition and subsequent help-seeking decisions: a mixed methods study protocol

INTRODUCTION

Coronary heart disease (CHD) is one of the leading causes of death in both men and women worldwide. Despite the common misconception that CHD is a 'man's disease', it is now well accepted that women endure worse clinical outcomes than men following CHD-related events. A number of studies have explored whether or not gender differences exist in patients presenting with CHD, and specifically whether women delay seeking help for cardiac conditions. UK and overseas studies on help-seeking for emergency cardiac events are contradictory, yet suggest that women often delay help-seeking. In addition, no studies have looked at presumed cardiac symptoms outside an emergency situation. Given the lack of understanding in this area, an explorative qualitative study on the gender differences in help-seeking for a non-emergency cardiac events is needed.

METHODS AND ANALYSIS

A purposive sample of 20-30 participants of different ethnic backgrounds and ages attending a rapid access chest pain clinic will be recruited to achieve saturation. Semistructured interviews focusing on help-seeking decision-making for apparent cardiac symptoms will be undertaken. Interview data will be analysed thematically using qualitative software (NVivo) to understand any similarities and differences between the way men and women construct help-seeking. Findings will also be used to inform the preliminary development of a cardiac help-seeking intentions questionnaire.

ETHICS AND DISSEMINATION

Ethical approvals were sought and granted. Namely, the University of Westminster (sponsor) and St Georges NHS Trust REC, and the Trust Research and Development Office granted approval to host the study on the Queen Mary's Roehampton site. The study is low risk, with interviews being conducted on hospital premises during working hours. Investigators will disseminate findings via presentations and publications. Participants will receive a written summary of the key findings.