European Journal of Cardiovascular Medicine

Metabolic syndrome (MetS) is a major health issue in the general population in which there is a cluster of interconnected metabolic disorders, which are strongly associated with the risk of developing coronary artery disease (CAD). This association of clustering cardiovascular risk factors has become one of the most significant predictors of atherosclerotic cardiovascular disease, and it is one of the most critical crossings of metabolic dysfunction and coronary pathology.

Metabolic syndrome was officially recognised by the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) in 2001, which specified MetS as meeting at least three of five criteria: large waist circumference (greater than 40 inches in men and greater than 35 inches in women), high blood pressure ([?]130/85mmHg), high fasting triglycerides (150mg/dl), low high-density lipoprotein cholesterol (less than 40mg The quality of this definition has made it one of the most used clinical criteria to identify people with a higher risk of cardiovascular disease because it is practical and has included easily available clinical measures[1][2].

Metabolic syndrome is highly disparate among populations and geographic areas. Research in the early 2000s showed that around 20-25 percent of the adult population in the world meets the criteria that are associated with MetS. The Framingham Offspring Study, a ground-breaking epidemiological study, found that metabolic syndrome patients were at high risk of cardiovascular events, and the syndrome was an independent predictor of coronary heart disease development. This primordial study defined the essential connection between metabolic dysfunction and cardiovascular pathology and showed that MetS is not merely the aggregate of its constituent elements.<|human|>This pioneering study identified the vital connection between metabolic dysfunction and cardiovascular pathology, proving that MetS is not just the sum of the parts.[3,4]

The causal pathophysiological processes of the interrelation between metabolic syndrome and coronary artery disease are complicated and multifactorial. The key aspect of this association is insulin resistance, acting as a unifying factor in the different factors of MetS to precipitated atherosclerosis. The insulin resistance facilitates endothelial dysfunction, elevates inflammatory markers and predisposes a prothrombotic condition which encourages the formation and progression of plaque in the coronary arteries. Metabolic pathophysiological alterations that are typical of MetS, visceral obesity, dyslipidemia, and glucose intolerance, interact collaboratively to develop the environment that facilitates an accelerated coronary atherosclerosis progression[5][6][7].

Actually, epidemiological data repeatedly prove the close interrelation of metabolic syndrome and cardiovascular morbidity and mortality. The Adult Treatment Panel III definition has been especially useful in the recognition of those at high coronary risk, with research having found that patients fulfilling the ATPIII criteria have the highest cardiovascular events relative to those without MetS. Studies carried out in various groups of people have indicated that patients with metabolic syndrome are at a higher risk of developing coronary artery disease by about 1.5-2 times, as compared to patients who do not have the syndrome[8][9].

The individual elements of metabolic syndrome contribute dissimilarly to the cardiovascular risk with some having stronger relationships with CAD than others. The combination of high triglycerides and low HDL cholesterol has become one of the most powerful predictors of coronary events among MetS components, which has become dyslipidemia. Equally, hypertension and belly obesity are risk factors that are independent and increase cardiovascular risk to a significant degree when they exist as members of the metabolic syndrome constellation.[10][11].

Research into the interaction between the severity of MetS and coronary artery disease has reported the existence of a dose effect interaction, with the presence of other metabolic abnormalities being associated with a greater severity and degree of coronary atherosclerosis. Multi-component patients with multiple MetS components are also more likely to have widespread coronary disease with increased multi-vessel involvement and complicated coronary lesions needing interventional therapy.

Clinical implications of identifying metabolic syndrome as a cardiovascular risk factor are not just restrictive to mere risk stratification. The definition of MetS gives clinicians a model that they can use to apply extensive lifestyle interventions addressing various cardiovascular risk factors at the same time. Further, metabolic syndrome also affects treatment choices in the management of lipids, blood pressure and antithrombotic therapy, and it is a useful clinical instrument in the streamlining of cardiovascular risk reduction protocols.

Study Design

This was a prospective observational study conducted over a period of 6 months at KLE Hospital, Belgaum, Karnataka, to evaluate the association between metabolic syndrome and coronary artery disease (CAD). The study aimed to assess the prevalence of metabolic syndrome components in patients diagnosed with CAD and to explore their potential correlation.

Study Population

The study included 50 patients who were diagnosed with CAD based on clinical and diagnostic criteria, including electrocardiogram (ECG), echocardiography, and coronary angiography. Patients were selected from the outpatient and inpatient departments of KLE Hospital during the study period. All patients provided informed consent before participation. Inclusion criteria included adult patients (age ≥18 years) who were diagnosed with CAD and had undergone the necessary diagnostic evaluations. Exclusion criteria included patients with a history of prior coronary bypass surgery, those with non-cardiac diseases that could interfere with metabolic parameters, or those with incomplete medical records.

Metabolic Syndrome Diagnosis

Metabolic syndrome was defined according to the International Diabetes Federation (IDF) criteria, which includes the presence of at least three of the following five components:

1. Abdominal obesity: Waist circumference ≥94 cm in males and ≥80 cm in females.
2. Elevated blood pressure: Systolic BP ≥130 mmHg or diastolic BP ≥85 mmHg, or on antihypertensive treatment.
3. Elevated fasting blood glucose: Fasting plasma glucose ≥100 mg/dL or on antidiabetic treatment.
4. High triglycerides: ≥150 mg/dL or on treatment for elevated triglycerides.
5. Low HDL cholesterol: <40 mg/dL in males and <50 mg/dL in females.

Patients were classified as having metabolic syndrome if they met the criteria for at least three of the above components.

Data Collection

A detailed clinical history and demographic information were recorded for each patient, including age, gender, smoking history, family history of CAD, and any other pre-existing medical conditions such as diabetes or hypertension. Blood samples were collected after an overnight fast for biochemical analysis of fasting blood glucose, lipid profile (total cholesterol, triglycerides, HDL, and LDL cholesterol), and other metabolic parameters.

Assessment of CAD

The diagnosis of CAD was confirmed through coronary angiography, which was performed for all patients in the study. Patients with confirmed CAD were classified according to the severity of the coronary artery involvement.

Statistical Analysis

Descriptive statistics were used to summarize patient demographics and clinical characteristics. The frequency and percentage of patients with each component of metabolic syndrome were calculated.

Table 1: Patient Demographics

This table provides an overview of the patient demographics in the study. It shows that 20% of the patients are less than 40 years old, while the majority (50%) are between 40 and 59 years old, and 30% are 60 or older. The gender distribution reveals that 60% of the patients are male, and 40% are female. This demographic distribution helps to identify potential patterns or trends in metabolic syndrome and coronary artery disease across different age and gender groups.

Table 2: Prevalence of Metabolic Syndrome Components

Table 2 outlines the prevalence of key components of metabolic syndrome among the 50 patients. The most common component is abdominal obesity, affecting 80% of the patients, followed by high blood pressure (70%) and high triglycerides (60%). Less common are low HDL cholesterol (40%) and elevated blood glucose (50%). These findings emphasize the widespread nature of metabolic syndrome and its individual components among the study group, which may contribute to cardiovascular risks.

Table 3: Presence of CAD in Patients with Metabolic Syndrome

Table 3 examines the association between metabolic syndrome and coronary artery disease (CAD). Of the 50 patients, 30 have metabolic syndrome, and within this group, 25 (83.33%) present with CAD, while only 5 (16.67%) do not. In contrast, only 5 patients without metabolic syndrome have CAD, and 15 do not. This table highlights a higher prevalence of CAD in those with metabolic syndrome, suggesting a strong association between the two conditions.

Table 4: Risk Factors in Patients with CAD

Table 4 details the prevalence of risk factors for CAD in the study sample. Hypertension is the most prevalent risk factor, affecting 50% of the patients, followed by a sedentary lifestyle (44%) and smoking (30%). Family history of CAD and diabetes mellitus are also common, affecting 36% and 40% of patients, respectively. These factors provide insight into the key lifestyle and health-related variables that may contribute to the development of CAD in the population studied.

Table 5: Association Between Metabolic Syndrome and CAD

Table 5 shows the direct relationship between the presence of metabolic syndrome and the likelihood of developing CAD. Of the 30 patients with metabolic syndrome, 25 (83.33%) have CAD, while only 5 (16.67%) do not. Conversely, in the 20 patients without metabolic syndrome, only 5 (25%) have CAD, while 15 (75%) do not. This table further strengthens the association between metabolic syndrome and CAD, indicating that patients with metabolic syndrome are significantly more likely to develop coronary artery disease.

Findings of this study underscore the close relationship between metabolic syndrome and coronary artery disease (CAD) in 50 patients who were cohorted. The patient demographic analysis shows that most of the patients are males (60%) and are aged between 40 and 59 years (50%), which is indicative of the general population trends and that this age range (middle-aged men) can be highly susceptible to both metabolic syndrome and CAD. This observation is in line with the historic Finnish Men Study by Lakka et al.,[12] which showed that men with metabolic syndrome had a risk of 2.9 to 4.2 times an increased likelihood of dying of coronary heart disease. On the same note, Beigh et al.[13] noted that metabolic syndrome prevalence in men and women were 23 and 29 percent respectively, respectively, and the disease had specific manifestations peculiar to each gender.<

The age and gender have historically been considered to be important determinants of cardiovascular diseases development, and older age and male sex are associated with increased risks of metabolic imbalance and CAD. The Framingham Offspring Study is a significant study that includes evidence that insulin resistance, the metabolic syndrome, and incident cardiovascular disease are closely related, and the syndrome is an independent predictor of coronary outcomes at enhanced age categories. Vishram et al.[14] proved that the trend of metabolic syndrome components was different between men and women, with young women having more obesity and low HDL-C, whereas young men had higher levels of high blood pressure and triglycerides.

The metabolic syndrome elements were very common in the study group, with highest prevalence being the abdominal obesity, high blood pressure, and high triglycerides. Abdominal obesity especially is a major risk factor of CAD since it is closely correlated with insulin resistance and systemic inflammation. Grundy et al. [15]has highlighted that metabolic syndrome is a multiplex cardiovascular risk factor and each of the components is a synergistic risk factor in coronary risk. Prasad et al.[16] emphasized that abdominal obesity is an independent risk factor in cardiovascular diseases in its own right, especially in its contribution to insulin resistance, dyslipidemia, and proinflammatory conditions. The fact that such metabolic abnormalities are high in the study group raises the possibility that the metabolic syndrome is not only prevalent but also a serious risk factor of cardiovascular diseases. The importance of treatment of the underlying metabolic disturbances in the prevention of CAD is supported by this finding.

CAD was found to be more highly prevalent in the patients who had metabolic syndrome, thus confirming the hypothesis that metabolic syndrome is an important determinant of CAD. Conversely, the patients with no metabolic syndrome were less diagnosed with CAD, which puts a high-risk exposure among patients with metabolic syndrome. This highlights the importance of metabolic variables in the causation of coronary artery disease and implies that metabolic syndrome can be used as an early warning system to determine people at greater risk of cardiovascular complications. Montazerifar et al. found that metabolic syndrome was present in 49.5 percent of CAD patients, and its prevalence was much greater in women (55.9 percent) than in men (40.2 percent). The researchers found that low HDL-C (84.8%), high levels of fasting blood glucose (77.8%), and high levels of waist circumference (75.8%) were the most common risk factors in CAD patients with a metabolic syndrome.[17].

The most notable risk factors including hypertension, smoking, sedentary lifestyle, diabetes, and family history of CAD were high in CAD patients and this corresponds with established cardiovascular risk factors. The fact that hypertension and sedentary behavior has a high prevalence in specifics speaks to the contribution of the lifestyle choice and underlying health conditions to the development of CAD. Hozawa et al.[18] revealed how smoking and hypertension interact in causing cardiovascular disease mortality and found out that the combination of the two factors explained 57.4 percent CVD mortality among young men. Equally, physical inactivity has been closely linked to metabolic syndrome with Bankoski et al. [19]demonstrating that those with metabolic syndrome were much more time in sedentary activities and took fewer sedentary time breaks.

When combined with metabolic syndrome, these risk factors that can be altered provide significant risk profile of cardiovascular diseases, which also underscores the importance of early detection and intervention. The results of Bachmann et al. indicated that a history of coronary heart disease in a family was correlated with an ongoing rise in CHD and CVD mortality risk over the course of long-term follow-up, which led to an approximate increase of their lifetime risk estimates by half. The co-location of classic cardiovascular risk factors and the components of metabolic syndromes makes their combination especially powerful with regard to the development of coronary disease, which leads to the idea that the change in the risk factors should be conducted comprehensively to prevent the cardiovascular disease development[20].

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