The study concludes with a call for comprehensive, evidence-based approaches to address this growing public health crisis.
Published Sep 09, 2025 | 7:00 AM ⚊ Updated Sep 09, 2025 | 7:00 AM
Representative image. Credit: iStock
Synopsis: The study identified several key risk factors that paint a nuanced picture of vulnerability patterns across Indian society. Smoking emerged as the most significant modifiable risk factor, with both current and former smokers facing nearly double the risk of developing obstructive lung disease.
While northern and western India grapple with the highest rates of obstructive lung disease in the country, south India presents a contrasting picture in the study, which provides the most reliable data available on lung disease burden in India for people above the age of 45.
A study published in PLOS One has revealed that nearly 14.4 percent Indians aged 45 and above are living with obstructive lung disease (OLD)—a condition that makes breathing difficult and includes illnesses such as chronic obstructive pulmonary disease (COPD), asthma, and chronic bronchitis. However, the research uncovered significant regional disparities that challenge previous assumptions about disease distribution across the subcontinent.
“Our estimates of geographic heterogeneity across India are also somewhat aligned with prior findings from the Global Burden of Diseases (GBD) study, with both studies finding higher prevalence in Northern and Western India and lower prevalences in Eastern and Northeastern India,” said the authors.
“However, GBD estimates found that the prevalence of COPD was fairly high in Southern India compared with other regions, while this was not the case in our data (Southern India had the fourth highest prevalence out of the six regions).”
The study, based on the Longitudinal Aging Study in India (LASI), represents a watershed moment in understanding respiratory health across the nation. Unlike earlier estimates that depended mainly on symptoms and self-reports, this research provides the most reliable picture so far of the burden of lung disease in India by using objective lung function tests (spirometry) on a nationally representative sample of over 31,000 adults.
The research revealed pronounced geographical variations in disease prevalence that paint a complex picture of respiratory health across India. Northern India recorded the highest prevalence at 17.2 percent, followed closely by Western India at 16.2 percent. In stark contrast, Northeast showed the lowest observed prevalence at 10.8 percent, while Southern India ranked fourth among the six regions studied.
“We observed heterogeneity across regions of India, with the highest observed prevalences in Northern, Western, and Central India and the lowest observed prevalences in Northeast and Eastern India,” said the authors.
This finding particularly challenges previous global burden estimates.
“Differences could potentially stem from the fact that representative data from the Burden of Obstructive Lung Disease studies were not available for areas in Southern India; therefore, GBD estimates relied on information from smaller studies, such as one study among nonsmoking rural women in the Tiruvallur district of Tamil Nadu,” said the authors. “Selected samples in these studies may lead to bias in overall estimates.”
The study’s methodology represents a significant advancement in respiratory health research in India. “This study is the first nationally representative study of middle-aged and older adults in India to utilise objective spirometry data and report the national and regional prevalence of obstructive lung disease measured via spirometry,” said the authors.
The research encompassed adults aged 45 years and older across India, with a sample size of 31,103 people who successfully completed spirometry tests. Data collection occurred between April 2017 and October 2021, with most spirometry data coming from 2017-18.
The study achieved near-complete geographic coverage, representing almost all states of India except Sikkim, where data collection could not be completed.
“Based on a nationally representative sample of adults aged 45 and above in India with objective spirometry data, we estimated that the prevalence of obstructive lung disease in adults 45 years and older was 14.4 percent,” said the authors.
The study uncovered demographic patterns that reveal the disease’s disproportionate impact across different population segments. Men showed significantly higher vulnerability than women, with 17.3 percent of men affected compared to 11.3 percent women. This gender disparity persisted across all age groups, though both sexes showed increasing risk with advancing years.
“In men, the prevalence of obstructive lung disease among 45–54-year-olds was 10.6 percent, approximately one-third of the prevalence estimate for men 75 years and older (32.2 percent),” said the authors.
“In comparison, an approximately two-fold difference in prevalence across age groups appeared for women, with an estimated prevalence of 7.9 percent in 45–54-year-olds and 18.1 percent in those 75 years and older.”
The age factor proved particularly dramatic among elderly men, where nearly one in three men aged 75 and above were affected by the condition.
“Estimates for gender suggest that the prevalence of obstructive lung disease was 26 percent lower among women than among men, adjusting for differences in age and smoking status,” said the authors.
Perhaps the most concerning finding of the study was the severe underdiagnosis of the condition across the country. The research revealed that fewer than 13 percent of patients knew they had a lung problem, highlighting what researchers describe as a critical awareness gap that threatens effective public health intervention.
“Only 12.0 percent of men and 11.0 percent of women with objective obstructive lung disease based on spirometry self-reported any prior diagnosis of lung disease, including COPD, chronic bronchitis, or asthma,” said the authors.
This awareness crisis varied by region, with particularly concerning patterns emerging.
“Though the prevalence of objective obstructive lung disease was highest in Northern India, the prevalence of self-reported lung disease was highest in Southern India, and disease awareness was lowest in the Northeast region,” said the authors.
The implications of this diagnostic gap are profound for healthcare planning and patient outcomes. “Prior work has highlighted issues around the underdiagnosis of COPD in India due to low disease awareness and the fact that diagnoses are typically not based on spirometry measurement but on self-reported symptoms,” said the authors.
The study identified several key risk factors that paint a nuanced picture of vulnerability patterns across Indian society. Smoking emerged as the most significant modifiable risk factor, with both current and former smokers facing nearly double the risk of developing obstructive lung disease.
Other significant risk factors included low body weight, often serving as a marker of poor nutrition and poverty, and a history of tuberculosis, with those affected by TB in the last two years facing significantly higher risk.
“We observed the strongest associations between obstructive lung disease and age, gender, and smoking status, though we also saw some evidence for associations with educational attainment and BMI,” said the authors.
Intriguingly, the study found patterns that differed from high-income countries.
“Counter to evidence from high-income settings, overweight and obesity were associated with a lower risk among the LASI cohort,” said the authors.
“However, in India, overweight and obesity are strongly associated with higher measures of SES, and protective associations have been observed across other health outcomes, indicating that benefits attributable to higher SES may offset potential negative health impacts of higher body mass in this setting.”
The relationship with indoor air pollution, while expected to be significant, proved more complex than anticipated.
“Although evidence suggests indoor pollution is an important risk factor for obstructive lung disease, in this study, the association between unclean cooking fuel use and obstructive lung disease was only marginally significant and was further attenuated after adjustment for smoking status,” said the authors.
The study’s findings align with and update previous global estimates while providing more precise regional data.
“Our prevalence estimates are higher than the estimated 7.4 percent or 7.0 percent prevalence of COPD from the two previous meta-analyses in India, though differences are likely largely attributable to differences in the age distributions of included studies,” said the authors.
When compared to updated global burden data, the Indian figures prove consistent with international patterns.
“Updated data from the GBD 2019 study yields estimates of 9.6 percent and 13.8 percent for COPD and the larger chronic respiratory disease category in adults 45 years and older. Our estimate of 14.4 percent is fairly consistent with the previously reported GBD estimate of 13.8 percent for all chronic respiratory diseases,” said the authors.
The study’s findings have profound implications for India’s healthcare system, which researchers note is already stretched thin. The high prevalence across all regions, combined with low awareness levels, demands comprehensive policy responses that address both prevention and treatment.
“Proposed reforms to improve the management of lung health in India have focused on supporting health promotion, early diagnosis, and disease management through several mechanisms, including strengthening primary care systems, improving access to technologies, drugs, and diagnostics, empowering patients and providers, and improving governance and accountability,” said the authors. “However, these campaigns have yet to be rolled out in a large-scale, national effort.”
Early intervention efforts show promise but highlight the scale of the challenge. “Initial findings from a novel primary care program to address COPD in Kerala suggested that the program did not affect the number of hospital or emergency department visits but did lead to greater availability of spirometry and inhalers and lower demand for injectable drugs and nebulisation due to better disease management,” said the authors.
The researchers emphasise that the scale and geographic spread of the problem demands coordinated national action rather than piecemeal regional responses.
“The high prevalence of obstructive lung disease in adults 45 years and older based on spirometry calls attention to obstructive lung disease as an important public health concern in India,” said the authors.
“Despite geographic heterogeneity, prevalence estimates were greater than 10 percent in all regions, suggesting that nationwide campaigns are needed in addition to targeted regional efforts.”
The study concludes with a call for comprehensive, evidence-based approaches to address this growing public health crisis.
“Ultimately, multifaceted, data-driven approaches are required to adequately address the burden of obstructive lung disease in India,” said the authors.
“Future campaigns should apply lessons learned from this initial effort to inform broader intervention programs targeting key areas including health system strengthening, providing low-cost and easily available technologies, drugs, and diagnostics, and improving the oversight and efficiency of designed programs.”
(Edited by Amit Vasudev)
