Chronic cough can have a significant impact on a patient’s quality of life, and recognizing it as an individual condition can help optimize their management.
Chronic cough (CC) can be debilitating for patients as it is a difficult disease to treat as a distinct condition unrelated to other systemic diseases. A recent study of the burden and impact of CC in a UK primary care setting found that recognizing CC as a distinct disease and detecting it earlier is critical to ensuring that patients are referred to specialists and treated appropriately.
CC, defined as a cough lasting 8 or more weeks in adults, has historically been viewed almost exclusively as part of other disease processes. However, in recent years it has been increasingly recognized as a disease that can be caused by a number of factors, including impaired neural sensitivity, peripheral activation imbalance, or altered central cough control.
“To date, only limited data are available describing the epidemiology, characteristics, and comorbid factors of individuals with CC in the general population,” the study authors write. Their retrospective, cross-sectional study aimed to provide insight into the experiences of patients with CC in the UK healthcare system and to assess healthcare utilization and costs of CC alone and with comorbid conditions.
Data for the study was drawn from a comprehensive data set containing medical records from more than 2.5 million people resident and registered with a General Practitioner (GP) in North West London. More than 360 GP organizations feed the data set.
The researchers identified 43,453 people aged 18 or older who had CC in more than 2 million patients at 350 primary care practices between 2015 and 2019, for an overall rate of 2%. In eligible patients, 2 or more consultations were recorded as cough-related, lasting at least 8 weeks.
Median patient age was 64 years and 31% of patients with CC had no reported comorbidities. Of the 30,102 (68%) with documented 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 solely due to their illnesses or was aggravated by an underlying hypersensitive cough. Angiotensin converting enzyme (ACE) inhibitors, which can trigger chronic cough, were prescribed to 14.6% of patients prior to the study’s index date.
In the CC cohort, smoking status was documented for 44.2%; 22.3% were current smokers and 18.8% were ex-smokers. Only 3.1% were non-smokers. All recorded comorbidities were more common in current or former smokers than in non-smokers.
The median delay between CC diagnosis and referral to an outpatient appointment was 4 months overall; 4 months for respiratory drugs; 5 months for ear, nose and throat diseases; and 5 months for gastroenterology. The overall median delay between the index date and the first outpatient visit was 6 months. There was also an overall increase in the number of examinations performed within 12 months of diagnosis in the CC cohort. These included chest X-rays in primary care (up 49%), spirometry in primary care (up 34%) and ambulatory spirometry (up 56%).
Although 56.6% of patients in the CC cohort had at least one antibiotic prescribed, 63% had no cough suppressant prescribed.
The outpatient cost per patient per year was also higher after CC was reported compared to before diagnosis. Among the reported comorbidities, reflux had the highest outpatient costs, followed by asthma and COPD, and smoking and rhinitis. The costs were also higher in patients with CC and without comorbidities than in patients without CC.
While the study was limited by the quality of data routinely entered by clinicians and the fact that some systems use free text input that could not be pulled into the data, the study authors concluded that more effort should be to recognize CC as its own condition with a range of phenotypes. Then, processes for diagnostic testing and treatment trials can be streamlined to improve the patient experience and enable rapid referral and targeted treatment.
Hull JH, Langerman H, Ul-Haq Z, Kamalati T, Lucas A, Levy ML. Burden and impact of chronic cough in UK primary care: a data set analysis. BMJ open. Published online December 17, 2021. doi:10.1136/bmjopen-2021-054832