NEW DELHI: More than one in 10 deaths globally was caused due to smoking in 2015 and over 50 per cent of them took place in just four countries, one of which was India , a new study today said.Over 11 per cent of 6.4 million deaths worldwide was caused by smoking in 2015 and 52.2 per cent of them took place in China , India, USA , and Russia , according to the latest estimates in the Global Burden of Disease (GBD) study published in medical journal The Lancet.China, India, and Indonesia, the three leading countries with male smokers, accounted for 51·4 per cent of the world's male smokers in 2015.India has 11·2 per cent of the world's total smokers.Deaths attributable to smoking increased by 4.7 per cent in 2015 compared with 2005 and smoking was rated as a bigger burden on health - moving from third to second highest cause of disability, the study said."In 2015, 11·5 per cent of global deaths (6·4 million) were attributable to smoking worldwide, of which 52·2 per cent took place in four countries - China, India, the USA, and Russia)," the study said.The estimates are based on smoking habits in 195 countries and territories between 1990 and 2015, and illustrate that smoking remains a leading risk factor for death and disability.The study said that with growing and ageing populations already heightening the burden of tobacco, it will be crucial to support more smokers in quitting and stopping people from starting to smoke."The USA, China and India, which were the leading three countries in total number of female smokers, accounted for only 27·3 per cent of the world's female smokers," it said.While Indonesia, Bangladesh and the Philippines did not have significant reductions in male prevalence of daily smoking since 1990, the Philippines, Germany, and India had no significant decreases in smoking among women.The authors of the study warned the war against tobacco is far from won, and argued that despite implementation of the WHO Framework Convention on Tobacco Control in 2005, policy makers need to make renewed and sustained efforts to tackle it.Worldwide, between 1990 and 2015, smoking prevalence decreased by almost a third-- from 29.4 per cent to 15.3 per cent-- and presently one in four men (25 per cent) worldwide smoke, as do one in nearly 20 women (5.4 per cent).Despite these improvements, population growth has led to an increase in the overall number of smokers from 870.4 million in 1990 to 933.1 million in 2015, the study said.The study said Pakistan, Panama and India stand out as three countries that have implemented a large number of tobacco control policies over the past decade and recorded marked declines in the prevalence of daily smoking since 2005, compared with decreases recorded between 1990 and 2005.The study said the Framework Convention on Tobacco Control (FCTC), is necessary and vital for creating policy environment for more effective tobacco control worldwide but in not enough to fully address each country's tobacco-control needs.The nations will need to both implement FCTC-stipulated measures and supplement such policies and programmes with strong enforcement and high rates of compliance, it said."For example, India, where 11·2 per cent of the world's smokers live, supplemented the Cigarettes and Other Tobacco Products Act (COTPA) with the creation of a National Tobacco Control Programme (NTCP) in 2007."NTCP was created to strengthen implementation and enforcement of the various provisions of COTPA at the state and district level. It has been rolled out in phases and currently covers about 40 per cent of all districts in India," the study said.The 10 countries with the largest number of smokers in 2015 were China, India, Indonesia, USA, Russia, Bangladesh, Japan, Brazil, Germany and the Philippines.Together they accounted for almost two-thirds of the worlds smokers (63.6 per cent), the study said."Despite more than half a century of unequivocal evidence of the harmful effects of tobacco on health, today, one in every four men in the world is a daily smoker."Smoking remains the second largest risk factor for early death and disability, and so to further reduce its impact we must intensify tobacco control (efforts)," said senior author Emmanuela Gakidou, Institute for Health Metrics and Evaluation at the University of Washington, USA.