Chronic diseases seldom occur in isolation, and the intersection of pulmonary and metabolic disorders is an area of growing clinical concern. COPD affects millions worldwide, contributing to significant healthcare burdens due to its progressive nature and frequent comorbidities [1]. Cardiovascular disease (CVD) is one of the most prevalent and fatal comorbid conditions in COPD patients [2]. Similarly, type 2 diabetes mellitus (T2DM) shares common risk factors with both COPD and CVD, including systemic inflammation, smoking history, sedentary lifestyle, and aging [3].

The Framingham Risk Score, developed from the Framingham Heart Study, offers a well-established model for estimating a 10-year cardiovascular event risk based on variables such as age, gender, cholesterol levels, blood pressure, smoking status, and diabetes [4]. However, its predictive accuracy in populations with chronic inflammatory diseases like COPD requires further scrutiny [5].

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease that limits airflow from the lungs and is a major cause of morbidity and mortality globally. The World Health Organization (WHO) reported that COPD was the third most common cause of death in the world in 2019, with 3.23 million deaths [1]. Inflammation, oxidative stress, and systemic features of COPD are now recognized as causes of cardiovascular morbidity and mortality [2].

A large proportion of COPD patients also have metabolic disorders, the most common of which is diabetes mellitus (DM). Chronic inflammation that is a part of COPD stimulates insulin resistance and metabolic derangement, pathophysiologically connecting it with diabetes [3]. Diabetes, on the other hand, enhances pulmonary inflammation and accelerates lung function decline. This two-way association not only aggravates clinical courses but also enhances the risk of cardiovascular diseases (CVD).

The Framingham Risk Score (FRS), which is derived from the original Framingham Heart Study, is a precious tool for estimating 10-year risk of developing cardiovascular events [4]. It uses age, sex, smoking status, blood pressure, cholesterol, and diabetic status, providing a quantitative estimate of future cardiovascular risk.

Against this backdrop of interrelations, assessment of cardiovascular risk in COPD patients, particularly those with coexistent diabetes, assumes high priority. Yet, there is little information available on the use of the FRS in dual-pathology cohorts. This research seeks to bridge this gap by measuring Framingham cardiovascular risk scores in COPD subjects, stratifying them according to diabetic status, and examining demographic factors like age and gender.

COPD and Cardiovascular Disease

COPD is defined by chronic respiratory symptoms and limitation of airflow caused by airway and/or alveolar disease. In addition to pulmonary pathology, COPD is linked with systemic inflammation and endothelial dysfunction, both of which enhance atherogenesis and increase cardiovascular risk [6].

The Framingham Risk Score

The FRS predicts the risk of developing CVD in 10 years [4]. Although it has been confirmed in the general population, the inflammatory environment of COPD could independently increase cardiovascular risk above what is reflected by traditional measures [5][7].

COPD, Diabetes, and Cardiovascular Risk

COPD patients have insulin resistance and metabolic derangements, which heighten the risk of developing T2DM [8]. Diabetes itself is a powerful multiplier of cardiovascular risk, and there are concerns that using standard risk calculators will fail to accurately calculate true risk in COPD patients with coexistent diabetes [9][10].

Study Design and Population

This was a cross-sectional, observational, hospital-based study carried out at a tertiary care facility over a period of 12 months. The design was chosen as it allows assessment of the prevalence of cardiovascular risk in COPD patients with and without diabetes at a single point in time, providing a snapshot of associations without the need for long-term follow-up. Ethical clearance was obtained from the Institutional Review Board before initiation of the study, and all participants provided written informed consent.

A total of 48 subjects were recruited during the study period. Patients were selected through consecutive sampling from the outpatient and inpatient departments of pulmonary medicine. Of the total cohort, 24 were diagnosed cases of COPD without diabetes, while 24 had coexisting type 2 diabetes mellitus (T2DM) in addition to COPD. The diagnosis of COPD was confirmed according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria, specifically requiring a post-bronchodilator ratio of forced expiratory volume in one second to forced vital capacity (FEV₁/FVC < 0.70) on spirometry.

Patients were stratified into groups based on their diabetic status and further analyzed by age, gender, and Framingham Risk Score (FRS) categories. The comparison of cardiovascular risk burden between the two groups was a primary objective, along with exploring the correlation between COPD, diabetes, and 10-year predicted cardiovascular risk.

Inclusion Criteria

Participants were included if they fulfilled the following:

• An established diagnosis of COPD confirmed by spirometry (post-bronchodilator FEV₁/FVC < 0.70).
• Age between 30 and 75 years, ensuring both younger adults at risk and older patients were captured while excluding extremes where comorbidities may confound findings.
• Both males and females were considered, allowing gender-based comparisons.
• For the diabetic subgroup: established diagnosis of type 2 diabetes mellitus, defined as HbA1c ≥ 6.5% or ongoing use of oral hypoglycemic agents or insulin therapy. This threshold aligns with American Diabetes Association (ADA) diagnostic criteria.

Exclusion Criteria

To avoid confounding and ensure the cardiovascular risk assessed was primarily attributable to COPD and diabetes, patients with the following conditions were excluded:

• Pre-existing cardiovascular diseases (history of myocardial infarction, angina, coronary revascularization, stroke, or heart failure), as their inclusion would skew the baseline cardiovascular risk estimation.
• Severe renal impairment, defined as estimated glomerular filtration rate (eGFR < 30 mL/min/1.73m²), as chronic kidney disease itself is a strong independent cardiovascular risk factor.
• History of malignancy, given its systemic effects on metabolism and survival outcomes.
• Pregnant women, because of physiological changes in lipid profile, blood pressure, and cardiovascular dynamics that may interfere with risk calculation.

Data Collection and Variables

Comprehensive demographic and clinical information was obtained using structured proformas. Variables included:

• Sociodemographic data: age, sex, socioeconomic status, occupation.
• Smoking history: pack-years were calculated to quantify cumulative exposure.
• Clinical details: COPD duration, GOLD staging, presence of respiratory symptoms, comorbidities, and treatment history.
• Anthropometric measurements: height, weight, and body mass index (BMI).
• Blood pressure: measured using a standard mercury sphygmomanometer with patients in a seated position, average of two readings.
• Laboratory investigations: fasting blood glucose, glycated hemoglobin (HbA1c), complete lipid profile (total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides). [4]

Framingham Risk Score (FRS) Assessment

For each participant, the Framingham 10-year cardiovascular risk score was calculated using the validated algorithm. The following variables were incorporated:

• Age
• Sex
• Total cholesterol
• High-density lipoprotein (HDL) cholesterol
• Systolic blood pressure
• Current use of antihypertensive medication
• Smoking status (current or former)
• Diabetes mellitus status

The scoring system estimates the probability of developing cardiovascular events (coronary heart disease, stroke, peripheral vascular disease, or heart failure) within 10 years. Based on the calculated risk percentage, subjects were stratified into categories:

• Low risk: <10%
• Intermediate risk: 10–20%
• High risk: >20%

This stratification allowed for a comparative evaluation of cardiovascular risk burden between COPD-only patients and those with concurrent diabetes.

Quality Control

To maintain accuracy and minimize observer bias:

• All spirometry was performed using the same calibrated spirometer, adhering to ATS/ERS guidelines.
• Laboratory tests were conducted in the hospital’s accredited central laboratory using standardized enzymatic methods.
• Blood pressure was measured using the same validated equipment for all participants.
• The FRS calculation was performed using the standard online calculator provided by the Framingham Heart Study website, ensuring consistency.

Statistical Analysis

All data were compiled and analyzed using SPSS version 26.0 (IBM Corp., Armonk, NY, USA). Continuous variables such as age, BMI, lipid levels, and FRS were summarized as means ± standard deviation (SD), while categorical variables (e.g., gender, smoking status, risk categories) were expressed as frequencies and percentages.

• Chi-square test was applied to examine associations between categorical variables such as gender distribution and cardiovascular risk categories across groups.
• Independent Student’s t-test was used for comparison of continuous variables like mean FRS between COPD-only and COPD-diabetes groups.
• Correlation analysis (Pearson or Spearman as appropriate) was employed to evaluate the relationship between diabetes status, COPD severity, and FRS.
• A p-value of <0.05 was considered statistically significant.

This analytical approach enabled the exploration of both group-wise differences and linear associations, thereby strengthening the validity of conclusions drawn.

Age-Wise Distribution

The majority of participants in both groups were under 50 years of age:

• In the COPD-only group, 41.66% were aged 30–39, and 37.5% were in the 40–49 range.
• In the COPD with diabetes group, 29.16% were aged 30–39, and the largest proportion (45.83%) were in the 40–49 range.
• The presence of older age (>60 years) was modest in both groups but higher in the COPD with diabetes cohort (8.33%) compared to COPD-only (4.16%).

Framingham Risk Score Distribution

• Among COPD-only patients, 67.75% fell into the low-risk category (<10% 10-year risk), while 17.64% were classified as high-risk.
• Notably, COPD patients with diabetes showed a stark contrast: only 32.25% were low-risk, while a significant 82.35% were categorized as high-risk.

Gender Distribution in Risk Categories

• Among men (n = 27), 25.92% in the youngest age group (30–39 years) were low-risk, while 7.4% in the same group were high-risk.
• In women (n = 21), younger participants (30–39 years) represented 28.57% of the low-risk category, and notably, none were classified as high-risk.
• In older age groups, particularly in men aged 40–49, there was a shift toward higher risk scores (18.51% high-risk), indicating age and gender interplay in risk stratification.

Age-Wise Distribution of Study Population

• The study population exhibited a diverse age distribution. In the COPD-only group, the majority (41.66%) were aged between 39–39 years, followed by 37.5% in the 40–49 age bracket. In contrast, the COPD with diabetes group displayed a higher proportion (45.83%) in the 40–49 age range, indicating a shift towards older individuals.

Distribution According to Framingham Risk Scores

• A significant disparity was observed between the two groups when stratified by Framingham Risk Scores. The majority of COPD-only patients (67.75%) fell within the low-risk category, whereas a concerning 82.35% of COPD with diabetes patients were classified as high risk.

Gender and Age Stratification

• Further analysis revealed gender disparities in age and risk distribution. Among men (n=27), the 39–39 age group represented 25.92%, while in women (n=21), it was slightly higher at 28.57%. Notably, men demonstrated higher proportions in high-risk categories across most age brackets.

Framingham Risk Scores by Gender and Age Group

The study findings highlight several key observations:

First, though younger age groups (30–49 years) predominate the COPD population in this study, high Framingham risk scores in these age groups—particularly among diabetic COPD patients—indicate premature cardiovascular risk accumulation. This is consistent with earlier research reporting premature cardiovascular aging in COPD populations [11].

Secondly, gender-specific patterns reflect subtle variation. While female patients with COPD in early middle age by and large are in the low-risk group, the same aged male patients have increasing rates of raised risk scores. This would imply that COPD male patients, especially in those with the associated diabetes, are deserving of aggressive cardiovascular management even at a young age [12].

Third, the obvious increase in risk score classification in COPD patients with diabetes highlights the insufficiency of managing these comorbidities separately. The Framingham Risk Score, while useful, does not include the entire range of risk factors common in COPD populations, including chronic inflammation, recurrent exacerbations, hypoxemia, or the cardiovascular effect of prolonged corticosteroid treatment [13][14].

These findings call for a more balanced strategy of cardiovascular risk estimation in COPD patients. Combining conventional risk scores with disease-related factors, along with vigorous control of metabolic comorbidities such as diabetes, is crucial. Standardized cardiovascular screening, lifestyle modification, and personalized pharmacotherapy must be the building blocks of total COPD care [15].

This research emphasizes the significant effect of diabetes on cardiovascular risk in patients with COPD. Our results are in accordance with current literature, which indicates that comorbid diabetes significantly increases the risk of cardiovascular events in COPD patients [5].

Age and Risk Correlation

The age distribution highlights that cardiovascular risk increases with increasing age, especially in those with coexisting diabetes. The COPD with diabetes cohort had a greater proportion of patients in the 40–49 and >60 years age groups, which are classically representative cohorts with rising vascular susceptibility due to chronic exposure to risk factors like systemic inflammation, oxidative stress, and endothelial dysfunction [6].

Interestingly, whereas a high proportion of the COPD-only cohort were younger (39–39 years), they had lower Framingham risk scores, highlighting the synergistic impact of diabetes and age on cardiovascular risk. This is consistent with studies suggesting that metabolic derangement in diabetes combines with COPD-induced systemic inflammation to accelerate vascular pathology [7].

Gender Disparities

Gender-stratified analysis indicated that men had consistently elevated Framingham risk scores across all age groups in comparison to women. This has been supported by the Framingham Heart Study, which confirmed that male gender, as an independent factor, adds to cardiovascular risk [4]. Biological explanations such as androgen-mediated lipid patterns and increased prevalence of smoking in men in specific populations could underlie this difference [8].

But importantly, it must be observed that there is new appreciation for underdiagnosed cardiovascular risk among women with COPD, perhaps because of different symptom presentation and traditionally lower prevalence of cardiovascular screening in women [9].

COPD and Diabetes Synergy

The interaction between COPD and diabetes seems to increase cardiovascular risk to a significant degree. In our series, 82.35% of patients with COPD and diabetes were found to be high risk by Framingham scoring compared with only 17.64% in the COPD alone group. This staggering disparity emphasizes the additive weight of metabolic and respiratory dysfunction on cardiovascular morbidity.

Mechanistically, chronic hyperglycemia hastens atherosclerosis, induces endothelial dysfunction, and increases oxidative stress — all of which are pathways already triggered in COPD [10]. The presence of these conditions thus creates a "perfect storm" for cardiovascular pathology.

Clinical Implications

The results of our study highlight the importance of proactive cardiovascular risk assessment in COPD patients, especially those with coexistent diabetes. The use of tools such as the Framingham Risk Score allows for early detection of high-risk patients who can be treated with aggressive risk factor modification, such as smoking cessation, glycemic control, lipid management, and antihypertensive therapy.

In addition, our findings recommend interdisciplinary cooperation between pulmonologists, endocrinologists, and cardiologists to create holistic treatment plans for this at-risk group.

Limitations

Although our analysis is informative, some limitations have to be respected. The number of participants in the sample was small, perhaps compromising generalizability. In addition, cross-sectional design is not amenable to causal conclusions. Larger longitudinal studies are to be conducted to confirm these data and assess effects of risk-reduction interventions on the outcome measures.

COPD patients, particularly those with concomitant diabetes, have a greatly increased cardiovascular risk profile as estimated by the Framingham Risk Score. The preponderance of high-risk scores in this subgroup highlights the necessity for comprehensive, multidisciplinary care approaches. Although the Framingham score is informative, the limitations of this score in the COPD-diabetes population necessitate additional risk assessment measures to allow accurate stratification and prompt intervention.

This research supports the high increase of cardiovascular risk among COPD patients with associated diabetes, as established by the Framingham Risk Score. Male gender and age appeared to be vital risk amplifiers. Incorporation of cardiovascular risk evaluation into clinical COPD care, especially for diabetic patients, is necessary in order to avoid poor cardiovascular outcomes.

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