Statistical methods
Statistical analyses were performed using the Statistical Package for
the Social Sciences for Windows (SPSS version 22,0; IBM Corp, Armonk,
NY, USA). The relationships between the demographic data, HEMII-pH,
symptoms and sleep findings were investigated through multivariate
analysis. The outcome comparison between patient groups (LPR + OSASversus LPR) was performed through Mann-Whitney U Test. A level of
significance of p<0.05 was used.
Results :
A total of 89 patients completed the study. There were 45 patients with
LPR and 44 subjects with both OSAS and LPR. The demographic and
epidemiological data of both groups are described in Table 1. Patients
with OSAS and LPR had significant lower proportions of esophagitis,
hiatal hernia and gastritis compared with LPR patients. OSAS individuals
had higher BMI than patients without OSAS (p=0.001). Table 2 reports the
clinical presentation of LPR of both groups. The following symptom
scores of LPR patients with OSAS were significantly lower than the
scores of those with LPR: dysphonia; throat pain; throat clearing;
excess throat mucus and ear pressure/pain. Thus, otolaryngological RSS
and related quality of life (QoL) RSS were lower in patients with OSAS
and LPR compared with LPR patients.
The HEMII-pH profiles of patients are available in Tables 3 and 4.
Irrespective to the daytime period, patients with LPR had significant
higher number of acid and nonacid HREs than patients with OSAS and LPR.
Both groups were comparable regarding the nighttime HREs and the GERD
features.
The PSG features of patients with both OSAS and LPR are described in
Table 5. There were 12 and 13 individuals with mild (AHI: 5-15) and
moderate (AHI: 16-30) OSAS, respectively. Nineteen patients had severe
OSAS according to the AHI (>30). There were significant
associations between ESS, BMI (rs=0.491; p=0.003), QoL
RSS (rs=0.549; p=0.001) and the number of HREs in the
evening (rs=0.415; p=0.015). The multivariate analysis
revealed that patients with longer paradoxical sleep had higher RSS
(rs=0.399, p=0.009). There was no additional significant
association in the OSAS population and in subgroups of patients
regarding AHI categories. There was no significant association between
the severity of OSAS and the severity of LPR in the cohort. The analysis
of the occurrence of arousals and hypopharyngeal reflux events revealed
that only 3 patients had nighttime HREs, and, among them, the HREs were
not followed by arousals/awakenings.
Subgroup analysis reported that the presence of GERD at the HEMII-pH was
associated with a high number of HREs in patients with OSAS, especially
nighttime (Table 6). There was a statistical trend in the association
between DeMeester score and AHI (rs=0.539; p=0.070).
Sleep outcomes did not differ between OSAS patients regarding the
presence of GERD.