One in 10 people identified as having chronic obstructive pulmonary disease have no definitive diagnosis, yet the majority are being prescribed inhaled drugs, according to researchers.
Their study of 16,479 COPD patients across Hampshire has shown that 10% had no evidence of airflow obstruction to support their diagnosis, and yet 79% were receiving inhaler treatments.
“There is concern that the prescriptions given may not always be appropriate”
In total, 1.2 million people in the UK have been diagnosed with COPD. There are 30,000 deaths from the disease in the UK each year.
The study was prompted by the National COPD Audit Programme in 2016, which revealed that in a quarter of cases nationwide spirometry values were not consistent with the given diagnosis of COPD.
The Southampton University team looked at data on characteristics, medication and other conditions in patients diagnosed with COPD, comparing those with and without evidence of airflow obstruction.
Next, the researchers carried out analysis to question whether there was an asthma diagnosis that might explain the study findings, since similar inhalers are prescribed for both conditions.
Yet, even after excluding all patients with a diagnosis of asthma, which left 12,235 patients with COPD, 1,182 still had no evidence of airflow obstruction from a spirometry test.
“There may be other causes for their symptoms which have been missed”
But 50% of these were receiving long-acting bronchodilator inhalers and 50% were receiving inhaled corticosteroids, both of which are only recommended for confirmed, moderate or severe COPD.
Only 28% of patients were on no respiratory treatment, according to the new research presented today at the British Thoracic Society’s 2017 Winter Meeting in London.
Dr Lynn Josephs, who led the research, said: “It is well known that there is under-diagnosis of COPD and this is a major problem, yet this study highlights an additional issue that there are also a considerable number of cases of over-diagnosis.
“Without confirmatory spirometry testing, which is fundamental to diagnosis, a high number of patients were still diagnosed with, and given medication for, COPD,” said Dr Josephs.
“Since there is no evidence of COPD, nor of asthma in some cases, there is concern that the prescriptions given may not always be appropriate – either being ineffective or potentially harmful to those patients,” she said.
“We would advocate a reassessment of such patients, as there may be other causes for their symptoms which have been missed, and alternative treatment options,” she said.
She added: “Both under-diagnosis and over-diagnosis of COPD highlight the need for adequate access to quality assured spirometry in primary care.”