Just over one million smokers were admitted to hospitals in England between April 2010 and March 2011 and received 2.6 million episodes of care, according to calculations published online in Thorax on 10 November 2014
It is the first time researchers have put a figure on the prevalence of inpatients who are smokers in hospitals in England.
The researchers came up with the figures by identifying the smoking status of patients aged over 15 registered with 72 general practices and then linking those patients to national data on hospital stays.
They found that 80,000 people experienced 172,537 finished episodes of consultant-led care in hospital between April 2010 and March 2011. Of these, 17% (or one in six) were current smokers and 30.2% ex-smokers.
When the researchers looked at hospital speciality, they found that the prevalence of current smokers was more than twice as high for patients treated for mental illness compared with other specialities.
The researchers, from the UK centre for Tobacco and Alcohol Studies at the University of Nottingham and the Institute for Lung Health at Glenfield Hospital in Leicester, then used national population figures to calculate that between 2010 and 2011 there were 1.1 million smokers who were treated as inpatients in hospitals in England.
Their findings, they say, illustrate the potential impact of providing smoking cession services to inpatients, reflecting current national guidelines from the National Institute for Health and Care Excellence.
 Szatkowski L, Murray R, Hubbard R, et al. Prevalence of smoking among patients treated in NHS hospitals in England in 2010/2011: a national audit. Thorax. doi:10.1136/thoraxjnl-2014-206285 (accessed on 10 November 2014).