Authors:

Mohit Singh¹

Ajay Sharma²

Vinay Kumar³

Affiliations:

• ¹Rajshree Medical Research Centre, Bareilly, India

• ²Lala Lajpat Rai Memorial Medical College, Meerut, India

• ³Rohilkhand Medical College, Bareilly, India
  
  

Abstract

This study explores the bidirectional relationship between chronic respiratory diseases (CRDs) and cardiovascular diseases (CVDs) among middle-aged adults in semi-urban regions of northern India. A cross-sectional analysis of 210 participants aged 40–60 years was conducted, assessing pulmonary and cardiac functions. Findings indicate a significant overlap between CRDs and CVDs, with shared risk factors such as smoking, air pollution, and sedentary lifestyle contributing to the comorbidity. The study underscores the need for integrated screening and management approaches in semi-urban healthcare settings.

Introduction

Chronic respiratory diseases (CRDs), including chronic obstructive pulmonary disease (COPD) and asthma, and cardiovascular diseases (CVDs) like ischemic heart disease and heart failure, are leading causes of morbidity and mortality globally and in India. India bears a disproportionate burden, with CRDs accounting for a significant percentage of global disability-adjusted life years (DALYs) (Salvi & Agrawal, 2012). The coexistence of CRDs and CVDs is common, attributed to shared risk factors such as tobacco use, air pollution, and systemic inflammation (Barnes, 2009; Mannino & Buist, 2007).

Semi-urban areas in India, characterized by rapid urbanization and limited healthcare infrastructure, present unique challenges. Residents often face environmental exposures and lifestyle factors that predispose them to both CRDs and CVDs (Dey et al., 2012). Despite this, there is a paucity of data examining the interplay between these diseases in semi-urban Indian populations.

This study aims to investigate the bidirectional relationship between CRDs and CVDs among middle-aged adults in semi-urban settings of northern India, focusing on the prevalence, shared risk factors, and implications for integrated healthcare strategies.

Methods

Study Design and Setting

A cross-sectional observational study was conducted from April 2023 to March 2024 across three medical institutions: Rajshree Medical Research Centre (Bareilly), Lala Lajpat Rai Memorial Medical College (Meerut), and Rohilkhand Medical College (Bareilly).

Participants

The study included 210 adults aged 40–60 years with a documented history of either CRDs or CVDs. Inclusion criteria encompassed diagnosed cases of COPD, asthma, ischemic heart disease, heart failure, or hypertension. Exclusion criteria were the presence of diabetes mellitus, renal disease, or malignancies.

Data Collection

Participants underwent comprehensive evaluations, including:

• Pulmonary Function Tests (PFTs)
  
  

• Electrocardiography (ECG)
  
  

• Echocardiography
  
  

• Chest radiography
  
  

• Biochemical markers (e.g., B-type natriuretic peptide levels)
  
  

A structured questionnaire assessed demographic data, smoking history, exposure to biomass fuels, physical activity levels, and occupational exposures.

Statistical Analysis

Data were analyzed using SPSS version 22. Descriptive statistics summarized participant characteristics. Chi-square tests and t-tests evaluated associations between CRDs and CVDs. A p-value <0.05 was considered statistically significant.

Results

Demographics and Clinical Characteristics

Among the 210 participants, 124 (59%) were male, and 86 (41%) were female, with a mean age of 51.2 ± 5.8 years. CRDs were present in 95 participants (45%), CVDs in 85 participants (40%), and both conditions in 30 participants (15%).

Pulmonary and Cardiac Assessments

In participants with CRDs:

• 68% exhibited signs of right ventricular strain on ECG.
  
  

• Pulmonary hypertension was observed in 55% via echocardiography.
  
  

• Reduced left ventricular ejection fraction (<50%) was noted in 40%.
  
  

In participants with CVDs:

• 36% demonstrated obstructive patterns on PFTs.
  
  

• Chronic bronchitis symptoms were reported by 42%.
  
  

• A history of asthma was present in 28%.
  
  

Risk Factors

Common risk factors identified included:

• Smoking: 76%
  
  

• Biomass fuel exposure: 33%
  
  

• Air pollution exposure: 62%
  
  

• Physical inactivity: 51%
  
  

These factors were significantly associated with the coexistence of CRDs and CVDs (p<0.05).

Discussion

The study reveals a significant overlap between CRDs and CVDs among middle-aged adults in semi-urban northern India, underscoring the bidirectional relationship between these conditions. The high prevalence of shared risk factors, such as smoking and air pollution, contributes to this comorbidity (Gupta et al., 2018; Vupputuri et al., 2014).

Systemic inflammation serves as a common pathophysiological mechanism linking CRDs and CVDs. Inflammatory mediators released in chronic respiratory conditions can exacerbate atherosclerosis, leading to cardiovascular complications (Culpitt et al., 2005). Conversely, heart failure can impair pulmonary function through pulmonary congestion and reduced lung compliance (Fletcher et al., 2007).

The findings highlight the need for integrated healthcare approaches that address both respiratory and cardiovascular health, particularly in semi-urban settings where diagnostic resources may be limited (Agarwal et al., 2019).

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