The healthcare system is "failing" patients with a common respiratory condition, a new audit suggests.
Some chronic obstructive pulmonary disease (COPD) patients are regularly being admitted and discharged from hospitals on a "continuous cycle", the latest National COPD Audit Programme report states.
The report, from the Royal College of Physicians, found that 43% of patients admitted for hospital treatment of COPD were readmitted at least once in the three months following discharge - a "considerable" increase from the 33% readmission rate reported in 2008.
Many of the patients involved in the study had also been admitted in previous months and "appeared to be on a continuous cycle of hospital admission", the authors said.
They wrote: "The reasons for the high admission and readmission rates are unclear.
"Potential causes would be ineffective discharge processes, poor coordination between primary and secondary care services, inadequate community service provision, lack of social care, reduced threshold for admission, or the mere fact that the patient cohort has become increasingly hard to support out of hospital.
"However, whatever the reasons, the overriding impression provided by the data is of a system that is not only stressed, but is ultimately failing COPD patients."
But the audit, which draws on data from a variety of sources about patients cared for in England between February and April 2014, stresses that there have "undoubtedly been improvements in the safety and efficiency of COPD care", with the percentage of patients dying in hospital decreasing from 7.9% in 2003 to 4.3% in 2014.
Dr Robert Stone, consultant respiratory physician and clinical lead for the audit, said: "There have been some very encouraging improvements in efficiency and patient outcomes.
"However, it is clear from the data in this report that significant improvements must be made in order to support the needs of this complex and fragile patient group."
Commenting on the audit, Dr Penny Woods, chief executive of the British Lung Foundation, said: "This audit rightly emphasises the importance of a seamless journey between hospital and the community.
"This will mean vulnerable lung health patients can receive consistent and relevant care.
"We know that better planning and discharge support for patients with complex health conditions will help to prevent relapses and the need for readmission."
Meanwhile, experts have conducted a separate review into the deaths of people from two groups of respiratory diseases - COPD and Interstitial Pulmonary Diseases (IPD).
They found that many factors, including wealth, location and how many diseases they had, influenced whether patients who died from these conditions died at home or in hospital.
Researchers from King's College London's Cicely Saunders Institute studied the English national data set of all deaths over 14 years.
They found that 334,520 people died from COPD and 45,712 from IPD.
Two-thirds of people died in hospital and almost a fifth died at home.
The study, published in the journal BMC Medicine, found that people with more than one condition, those from deprived areas and people from urban areas were more likely to die in hospital.
London had the highest hospital deaths and the South West and South East coast had lower hospital deaths than most other regions.
Being married increased the chance of dying in hospital for COPD but not for IPD, the authors found.
The researchers suggest that this may show that when family members are present, they do not know what to do when breathlessness escalates which increases the chance of patients being admitted to hospitals.