According to a Global Burden of Disease study published in the Lancet Respiratory Medicine journal, 3.2 million deaths took place due to COPD while 0.4 million people died of asthma in 2015.
"The disease burden due to COPD in 2015 was highest in Papua New Guinea, India, Lesotho and Nepal, and burden for asthma was highest in Afghanistan, Central African Republic, Fiji, Kiribati, Lesotho, Papua New Guinea and Swaziland," it said.
India recorded 2774.64 prevalent cases of COPD per 100,000 people (2533-3027.38) and 4021.72 prevalent cases of asthma per 100,000 (3637.41-4,424.58) in 2015, the report said.
The study estimated the number of cases and deaths caused by the two conditions between 1990 and 2015 worldwide.
COPD is a group of lung conditions (including emphysema and chronic bronchitis) that cause breathing difficulties. The condition is largely caused by smoking and air pollution.
While overall prevalence and death rates had reduced since 1990, population growth and the ageing population meant that the numbers had increased, it said.
The number of deaths due to COPD increased by 11.6 per cent between 1990 and 2015 (from 2.8 to 3.2 million), and the number of cases increased by 44.2 per cent (from 121 to 174.5 million), the report said.
As a result of the larger number of cases, there were more people living with disability- with the countries with the highest burden of disability from COPD and asthma typically residing in developing regions, the study said. The study found that asthma was the most common chronic respiratory disease worldwide, with twice the number of cases of COPD in 2015, but that deaths from COPD were eight times more common than deaths from asthma.
Many cases of asthma and COPD can be treated or prevented with affordable interventions, but people are often left undiagnosed, misdiagnosed or undertreated.
The main risk factors for COPD were smoking and air pollution, followed by household air pollution, occupational risk (such as asbestos, diesel fumes, arsenic and benzene), ozone and second-hand smoke, leading the authors to call for public health interventions to bring down air pollution and further reduce global smoking rates.
"Conversely, the causes of asthma are less clear, but include smoking and asthma-causing allergens experienced in the workplace," the report said.
The authors highlighted the need for more research into causes of COPD and asthma to create better prevention measures and reduce the burden of the diseases, and also to help better define and diagnose the diseases.