Published online: February 11, 2020
Chronic cough (CC) is a cough lasting more than 8 weeks and has been associated with frequent health care visits, but little is known about the extent of its burden among patients with chronic cough who are managed by specialists. The three most common causes of CC are upper airway cough syndrome, previously referred to as post-nasal drip syndrome, asthma, and gastroesophageal reflux disease (GERD). A major challenge in identifying CC patients administratively is the lack of specific ICD-9 or ICD-10 diagnostic codes for CC.
The present retrospective observational study recently reported in The Journal of Allergy and Clinical Immunology: In Practice by Zeiger and colleagues set out to identify specialist-diagnosed CC patients 18-85 years of age in Kaiser Permanente Southern California (KPSC) using administrative pharmacy and healthcare resource utilization (HCRU) data in order to determine the disease burden of CC. To identify a targeted group of patients with a high probability of having CC, the research team used an internal KPSC specific CC encounter diagnosis code assigned by a specialist within one of four departments (pulmonologist, allergist, otolaryngologist, or gastroenterologist) in a KPSC clinic between 2013 and 2016. Clinical features and HCRU were determined in baseline and outcome years and were compared between the CC subgroups related to the presence or absence of GERD and common respiratory disorders. Also determined were the baseline factors associated with persistence of CC and a comparison of the CC cohort to a matched non-cough cohort
Of the 11,290 patients with specialist-diagnosed CC identified, 66.7% were female with an average age of 61 years. The CC cohort experienced frequent GERD (44.1%), asthma (31.2%), obesity (24.3%), upper airway cough syndrome (20.4%), common cough complications (19.4%), and hospitalizations (9.8%). The CC patients with both respiratory disease and GERD exhibited at baseline and follow-up: the most common cough comorbidities, higher HCRU, specialist care, dispensed respiratory and non-respiratory medications including proton pump inhibitors, antitussives, psychotherapeutics, oral corticosteroids and antibiotics than the other subgroups. A 40.6% persistence of CC occurred similarly between CC subgroups. Additionally, CC patients in the matched analysis also experienced significantly more comorbidities, laboratory evaluations, HRCU, and antitussives than non-cough patients. Specialist-diagnosed CC was associated with considerable disease burden, particularly among those with both respiratory disease and GERD.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.