Therapy and Palatal Surgery

Fig. 1

Flowchart using a theoretical model and an ideal form of positional therapy (PT) in OSA patients. OSA: obstructive sleep apnea, defined as an AHI ≥ 5.0. POSA: positional OSA, defined as an AHI ≥ 5 and an AHI in supine position twice or more as high when compared to each of the AHI values found in the other positions and a supine time between 10 and 90 %. Surgery would be the surgical procedure the patient had undergone. Non POSA: non positional OSA. PT: hypothetical ideal positional therapy, defined as reduction of supine time to 0, thereby reducing the AHI to the non supine AHI

Results

One hundred and thirty-nine patients were included; baseline patient characteristics are shown in Table 1. Fifty-two patients suffered from mild, 62 from moderate, and 25 from severe OSA. Fifty-nine patients were treated with UPPP (mild OSA 21, moderate 25, severe 13), 59 patients with UPPP+RFTB (mild OSA 23, moderate 26, severe 10), and 21 patients with ZPP+RFTB (mild OSA 8, moderate 11, severe 2).

Table 1

Baseline patient characteristics (n = 139) shown as median with full range

Variable	Median [range]
Age (years)	45.0 [25.0–69.0]
BMI (kg/m²)	27.4 [20.4–38.2]
AHI (/h)	18.0 [5.1–69.6]
AHI supine (/h)	30.2 [0.0–133.1]
% supine	34.1 [0.0–100.0]
Ratio male to female	127:12

Fifty-five patients (39.6 %) had a successful reduction in AHI, according to Sher’s criteria [32]. Twenty-seven out of 139 patients had a postoperative AHI < 5 (19.4 %). The median AHI of all 139 patients significantly decreased from 18.0 [range: 5.1–69.6] to 11.2 [1.0–63.0] (p < 0.001). The median AHI in all separate positions decreased significantly as well. The number of awakenings, total sleep time, and the percentages of total sleep time slept in supine, left, and prone positions did not change significantly after treatment (Table 2).

Table 2

Median polysomnographical parameters with interquartile range (IQR) before and after surgery (n = 139)

	Before		After		p-value
	Median	IQR	Median	IQR	p-value
AHI (/h)	18.0	12.0–27.0	11.2	5.6–20.2	<0.001
AHI supine (/h)	30.2	19.1–49.5	20.5	8.3–39.9	<0.001
AHI left (/h)	8.1	0.4–17.8	3.1	0.0–11.6	0.004
AHI right (/h)	4.4	0.0–17.5	2.6	0.0–7.6	0.008
AHI prone (/h)	0.0	0.0–11.1	0.0	0.0–0.9	0.024
AHI REM (/h)	21.4	11.3–33.5	12.8	4.9–21.9	<0.001
% supine	34.1	17.9–56.4	33.1	20.0–51.1	0.388
% left	24.1	6.2–41.2	29.7	11.0–41.7	0.389
% right	22.5	5.3–37.0	31.8	9.7–42.4	0.013
% prone	0.0	0.0–7.6	0.0	0.0–3.9	0.382
Total sleep time (minutes)	418.2	362.5–466.0	424.0	373.5–469.0	0.861
Desaturation index (/h)	5.7	2.1–12.7	3.8	1.4–9.4	0.001
Number of awakenings	4.0	2.0–6.0	4.0	2.0–7.0	0.499
Number of position changes	31.0	21.0–55.8	25.0	15.5–46.0	0.022
Positional change index (/h)	4.5	3.0–9.0	4.0	2.0–6.0	0.010

Bold-faced values represent significant differences

Treatment

No significant difference between the treatments was found in the number of patients with a successfully reduced AHI; in 27 patients treated with UPPP (CI: 32.7–59.2 %), in 21 patients treated with UPPP+RFTB (CI: 23.6–49.1 %), and in 7 patients treated with ZPP+RFTB (CI: 14.6–57.0 %) (p = 0.432), treatment was found to be successful. Data of patients treated with either UPPP+RFTB or ZPP+RFTB were pooled in one group (n = 80) and compared to the patients who underwent UPPP (n = 59). Between these groups only the percentage in supine position (increase in UPPP group, decrease in the other group) showed a significant difference between groups (Table 3).

Table 3

Median polysomnographical parameters with interquartile range (IQR) before and after palatal surgery with or without concurrent radiofrequent ablation of the base of the tongue

Treatment	UPPP (n = 59)					UPPP/ZPP + RFTB (n = 80)					p-value (between)
	Before		After		p-value (within)	Before		After		p-value (within)
	Median	IQR	Median	IQR	p-value (within)	Median	IQR	Median	IQR	p-value (within)
AHI (/h)	19.0	12.0–27.0	9.0	5.0–15.0	<0.001	17.7	12.1–25.1	12.7	6.8–24.4	0.002	0.069
AHI supine (/h)	30.6	13.8–50.7	13.7	6.4–34.8	<0.001	30.1	21.1–49.3	27.2	9.3–40.5	0.006	0.565
AHI left (/h)	8.2	0.0–18.9	2.7	0.0–12.1	0.005	6.8	1.1–15.2	3.3	0.2–11.3	0.193	0.199
AHI right (/h)	5.1	0.0–18.0	1.4	0.0–5.6	0.001	4.1	0.3–17.3	4.1	0.4–12.7	0.438	0.072
AHI prone (/h)	0.0	0.0–16.0	0.0	0.0–4.2	0.018	0.0	0.0–4.7	0.0	0.0–0.0	0.462	0.108
AHI REM (/h)	20.9	11.7–31.3	10.3	4.7–22.5	<0.001	21.6	9.7–33.8	13.2	6.2–21.9	<0.001	0.505
% supine	24.7	11.8–48.9	33.1	18.4–50.9	0.282	37.3	21.9–62.7	33.0	20.8–51.5	0.066	0.046
% left	27.0	0.0–42.9	28.9	12.3–43.6	0.499	23.4	7.0–41.2	30.7	10.8–39.7	0.582	0.823
% right	21.5	0.0–40.1	31.9	1.7–41.4	0.204	22.7	7.9–36.2	31.3	14.4–43.6	0.030	0.792
% prone	3.4	0.0–9.3	0.0	0.0–7.3	0.104	0.0	0.0–5.9	0.0	0.0–1.7	0.623	0.087
Total sleep time (minutes)	408.0	354.5–459.0	412.5	352.3–465.0	0.667	431.5	379.3–474.6	436.3	391.1–477.3	0.571	0.535
Number of awakenings	3.0	2.0–6.0	3.0	2.0–7.0	0.742	4.0	2.0–6.0	4.0	2.0–7.0	0.520	0.922
Number of position changes	27.0	18.0–48.5	24.5	15.8–47.5	0.517	33.0	21.0–58.0	30.0	15.0–45.0	0.015	0.277
Positional change index (/h)	4.0	2.0–8.5	4.0	2.0–7.0	0.260	5.0	3.0–9.0	4.0	2.0–6.0	0.014	0.377