UK Study Characterizes Patient, Health Care System Burden From Chronic Cough

Chronic cough (CC) can be debilitating for patients, as it is a difficult disease to treat as a standalone condition not related to other systemic diseases. A recent study on the burden and impact of CC in a primary care setting in the United Kingdom found that recognizing CC as a standalone condition and detecting it earlier are crucial to getting patients referred to specialists and given targeted treatment.

CC, defined as a cough lasting 8 or more weeks in adults, has been nearly exclusively considered a component of other disease processes in the past. But in recent years, it has become increasingly recognized as a disease that may be caused by a number of factors, including disordered neural sensitivity, disbalance of peripheral activation, or altered central cough control.

“To date, there are only limited data available describing the epidemiology, characteristics, and comorbid factors of individuals with CC in the general population,” the study authors wrote. Their cross-sectional retrospective study aimed to provide insight into the experience of patients with CC in the UK medical system and assess health care utilization and cost of CC alone and with comorbid conditions.

Data for the study were pulled from a comprehensive dataset of health care records for more than 2.5 million individuals residing in and registered with a general practitioner (GP) in North West London. More than 360 GP organizations feed the dataset.

Researchers identified 43,453 individuals aged 18 years or older who had CC from more than 2 million patients at 350 GP practices between 2015 and 2019, an overall rate of 2%. Eligible patients had 2 or more consultations recorded as cough-related persisting for at least 8 weeks.

The median patient age was 64 years, and 31% of patients with CC had no reported comorbidities. Of the 30,102 (68%) with recorded comorbidities, 26% had asthma, 17% had chronic obstructive pulmonary disease, 12% had rhinitis, and 15% had reflux. In these cases, it is unclear whether the CC was due entirely to their diseases or worsened by underlying hypersensitive cough. Angiotensin-converting enzyme (ACE) inhibitors, which can induce chronic cough, had been prescribed to 14.6% of patients before the study index date.

In the CC cohort, 44.2% had smoking status recorded; 22.3% were current smokers and 18.8% were former smokers. Only 3.1% were nonsmokers. All the comorbidities recorded were more prevalent in current or previous smokers vs nonsmokers.

The median delay between CC diagnosis and referral to an outpatient appointment was 4 months overall; 4 months for respiratory medication; 5 months for ear, nose, and throat disorders; and 5 months for gastroenterology. The median delay overall between index date and initial outpatient appointment was 6 months. There was also an overall increase in the number of investigations performed within 12 months post diagnosis in the CC cohort. These included primary care chest x-rays (49% increase), primary care spirometry (34% increase), and outpatient spirometry (56% increase).

Although 56.6% of patients in the CC cohort received a prescription for at least an antibiotic, 63% had not been prescribed any cough remedies.

Outpatient costs per patient per year were also higher after CC was reported compared with before diagnosis. Reflux had the highest outpatient costs of the comorbidities reported, followed by asthma and COPD and smoking and rhinitis. The cost was also higher in patients with CC and no comorbidities compared with patients without CC.

While the study was limited by the quality of data entered routinely by clinicians and the fact that some systems may use free text entries that could not be pulled into the data, the study authors concluded that more effort should be dedicated to recognizing CC as its own condition with a range of phenotypes. Then, processes for diagnostic testing and treatment trials can be optimized to improve the patient experience and allow prompt specialist referrals and targeted treatment.

Reference

Hull JH, Langerman H, Ul-Haq Z, Kamalati T, Lucas A, Levy ML. Burden and impact of chronic cough in UK primary care: a dataset analysis. BMJ Open. Published online December 17, 2021. doi:10.1136/bmjopen-2021-054832