Patients
This study was carried out of the rhinitis or rhinosinusitis patients
visiting Departments of Otorhinolaryngology at the Hospital District of
Helsinki and Uusimaa (HUS), Finland. The study (nro 31/13/03/00/2015)
was approved by the ethical committee of the Hospital District. Ethics
committee provided an approval that there was no need for written
informed consent for this retrospective follow-up study.
The inclusion criterion of the initial patient population (n = 5080) was
the ICD-10 diagnosis of J30., J31., J32., J33. or J01 registered in
outpatient visits for the years 2005, 2007, 2009, 2011 or 2013.
Longitudinal data of random patient samples were collected from
electronic health records (EHR), so that the sample size was the same
for each sampling year and each month of the sampling year. The last
data collection day of the follow-up data was 31.9.2019. CRS was defined
as having the diagnosis codes of J33. and/or J32. ESS was defined by the
operation codes (Table S2). The baseline visit was defined as the first
visit, and baseline ESS was the first ESS, found in the EHR at the given
sampling time. Revision ESS was defined as ESS that was performed after
the baseline ESS during the follow-up.
A total of 114/790 (14.7%) CRS patients underwent revision ESS in
(mean±stdev) 30.3±31.0 months after the baseline ESS (Figure S3A, Table
S4). Of the revised patients 91 had one revision ESS and 23 patients had
two or more revisions (Figure S3B).