Health-related quality of life in type 2 diabetes mellitus patients with different risk for obstructive sleep apnea

Figures & data

Table 1 Comparison of characteristics between groups with different risk for OSA based on STOP questionnaire

Parameter	Total (n=466)	Low-risk OSA group (STOP <2; n=154)	High-risk OSA group (STOP ≥2; n=312)	P-valuea
Age (years)	66.3±7.7	65.7±11.5	66.6±10.3	0.388
Male gender	223 (47.9%)	82 (53.2%)	141 (45.2%)	0.101
Body weight (kg)	85.0±17.4	80.2±15.5	87.4±17.8	<0.001
Body height (cm)	171.7±9.9	172.0±10.1	171.6±9.8	0.684
BMI (kg/m^2)	28.7±2.0	27.0±4.4	29.6±5.1	<0.001
Neck circumference (cm)	37.9±4.7	37.1±3.7	38.2±5.0	0.003
Waist circumference (cm)	101.9±13.5	98.2±12.2	103.7±13.8	<0.001
T2DM duration (years)	13.2±9.4	11.0±5.0	14.3±9.2	<0.001
HbA1c (%)	7.9±1.8	7.7±1.8	8.0±1.8	0.074
STOP score	2.1±1.1	0.8±0.4	2.7±0.7	<0.001
ESS score	5.7±4.4	4.0±3.3	6.5±4.5	<0.001
Insulin use	215 (46.1%)	67 (43.5%)	148 (47.4%)	0.423
Insulin therapy duration (years)	3.4±6.8	2.3±9.5	3.9±7.5	0.054
History of car accident	74 (15.9%)	19 (12.3%)	55 (17.6%)	0.142

Notes: Data are presented as mean ± standard deviation for quantitative variables and as number and percentage for qualitative variables;

a Student’s t-test for quantitative variables and chi-square test for qualitative variables.

Abbreviations: BMI, body mass index; HbA1c, glycated hemoglobin; T2DM, diabetes mellitus type 2; STOP, Snoring, Tiredness, Observed apnea, and high blood Pressure; ESS, Epworth Sleepiness Scale; OSA, obstructive sleep apnea.

Table 2 Comparison of comorbidites between groups with different risk for OSA based on STOP questionnaire

Parameter	Total (n=466)	Low-risk OSA group (STOP <2; n=154)	High-risk OSA group (STOP ≥2; n=312)	P-valuea
Asthma	42 (9.0%)	8 (5.2%)	34 (10.9%)	0.043
Depression	52 (11.2%)	14 (9.1%)	38 (12.2%)	0.319
GERD	132 (28.3%)	36 (23.4%)	96 (30.8%)	0.096
Arterial hypertension	358 (76.8%)	68 (44.2%)	290 (93.0%)	<0.001

Notes: Data are presented as number and percentage;

a chi-square test.

Abbreviations: OSA, obstructive sleep apnea; STOP, Snoring, Tiredness, Observed apnea, and high blood Pressure; GERD, gastroesophageal reflux disease.

Table 3 Comparison of daytime sleepiness based on ESS score between groups with different risk for OSA based on STOP questionnaire

Parameter	Total (n=466)	Low-risk OSA group (STOP <2; n=154)	High-risk OSA group (STOP ≥2; n=312)	P-valuea
ESS ≤6	297 (63.7%)	131 (85.1%)	166 (53.2%)	<0.001
ESS =7–8	76 (16.3%)	10 (6.5%)	66 (21.2%)
ESS ≥9	93 (20.0%)	13 (8.4%)	80 (25.6%)

Notes: Data are presented as number and percentage;

a chi-square test.

Abbreviations: ESS, Epworth Sleepiness Scale; OSA, obstructive sleep apnea; STOP, Snoring, Tiredness, Observed apnea, and high blood Pressure.

Table 4 Comparison of SF-36 variables between groups with different risk for OSA based on STOP questionnaire

Parameter	Total (n=466)	Low-risk OSA group (STOP <2; n=154)	High-risk OSA group (STOP ≥2; n=312)	P-valuea
Physical functioning	61.7±40.1	73.6±31.2	55.8±32.4	<0.001
Physical role limitations	46.8±49.9	58.4±42.7	41.1±41.9	<0.001
Bodily pain	51.6±27.6	67.2±28.3	50.8±29.3	<0.001
General health perception	41.2±29.4	45.9±15.0	38.8±17.4	<0.001
Social functioning	65.7±32.8	75.2±23.2	62.5±24.6	<0.001
Emotional role limitations	52.5±50.0	61.7±42.9	48.0±46.8	<0.001
Emotional well-being	66.7±28.1	65.2±16.51	56.2±16.9	<0.001
Vitality	59.2±24.0	66.5±25.8	50.1±27.1	<0.001

Notes: Data are presented as mean ± standard deviation;

a Student’s t-test for independent samples.

Abbreviations: OSA, obstructive sleep apnea; STOP, Snoring, Tiredness, Observed apnea, and high blood Pressure; SF-36, Medical Outcomes Study Short Form-36.

Table 5 Pearson’s correlation between SF-36 parameters and selected variables

Parameter	STOP score	ESS score	BMI, kg/m^2	Age, years	T2DM duration, years	Insulin therapy duration, years	HbA1c
	Ra (P-valueb)
Physical functioning	−0.29 (<0.001)	−0.002 (0.957)	−0.23 (<0.001)	−0.30 (<0.001)	−0.12 (0.011)	−0.11 (0.020)	−0.05 (0.321)
Physical role limitations	−0.26 (<0.001)	−0.08 (0.080)	−0.18 (<0.001)	−0.33 (<0.001)	−0.12 (0.008)	−0.08 (0.078)	−0.07 (0.129)
Bodily pain	−0.32 (<0.001)	−0.04 (0.393)	−0.22 (<0.001)	−0.31 (<0.001)	−0.12 (0.011)	−0.10 (0.032)	−0.04 (0.360)
General health perception	−0.26 (<0.001)	−0.20 (<0.001)	−0.23 (<0.001)	−0.07 (0.113)	−0.17 (<0.001)	−0.08 (0.096)	−0.03 (0.536)
Social functioning	−0.31 (<0.001)	−0.13 (0.005)	−0.20 (<0.001)	−0.03 (0.492)	−0.09 (0.050)	−0.09 (0.044)	−0.08 (0.105)
Emotional role limitations	−0.20 (<0.001)	0.008 (0.860)	−0.10 (0.031)	−0.12 (0.012)	−0.03 (0.464)	−0.04 (0.397)	0.02 (0.746)
Emotional well-being	−0.29 (<0.001)	−0.09 (0.054)	−0.09 (0.042)	−0.01 (0.945)	−0.14 (0.002)	−0.11 (0.015)	−0.08 (0.077)
Vitality	−0.33 (<0.001)	−0.05 (0.242)	−0.22 (<0.001)	−0.29 (<0.001)	−0.13 (0.005)	−0.10 (0.024)	−0.19 (<0.001)

Notes:

a R-value indicates Pearson’s correlation coefficient;

b Pearson’s correlation test.

Abbreviations: T2DM, diabetes mellitus type 2; HbA1c, glycated hemoglobin; BMI, body mass index; STOP, Snoring, Tiredness, Observed apnea, and high blood Pressure; ESS, Epworth Sleepiness Scale; SF-36, Medical Outcomes Study Short Form-36.

Table 6 Multiple linear regression analysis of STOP score and selected variables as independent predictors of SF-36 parameters

Parameter	STOP score	BMI, kg/m^2	Age, years	HbA1c, %	T2DM duration, years	Overall
	Ba (tb) P-value
Physical functioning	−6.37 (−4.80) <0.001	−1.40 (−4.77) <0.001	−0.99 (−7.58) <0.001	nsc	nsc	R^2 adjusted =0.201 F ratio =39.93 P<0.001
Physical role limitations	−7.21 (−4.16) <0.001	−1.43 (−3.72) <0.001	−1.44 (−8.43) <0.001	−2.15 (−2.15) 0.032	nsc	R^2 adjusted =0.196 F ratio =29.41 P<0.001
Bodily pain	−6.70 (−5.61) <0.001	−1.15 (−4.36) <0.001	0.91 (−7.80) <0.001	nsc	nsc	R^2 adjusted =0.216 F ratio =43.70 P<0.001
General health perception	−2.56 (−3.44) <0.001	−0.65 (−4.08) <0.001	nsc	nsc	−0.28 (−3.35) <0.001	R^2 adjusted =0.108 F ratio =19.84 P<0.001
Social functioning	−6.12 (−5.80) <0.001	−0.57 (−2.47) 0.014	nsc	nsc	nsc	R^2 adjusted =0.102 F ratio =27.46 P<0.001
Emotional role limitations	−8.14 (−4.28) <0.001	nsc	−0.46 (−2.39) 0.017	nsc	nsc	R^2 adjusted =0.047 F ratio =12.47 P<0.001
Emotional well-being	−4.61 (−6.57) <0.001	nsc	nsc	nsc	nsc	R^2 adjusted =0.083 F ratio =43.11 P<0.001
Vitality	−6.64 (−6.00) <0.001	−1.01 (−4.12) <0.001	−0.80 (−7.33) <0.001	nsc	nsc	R^2 adjusted =0.212 F ratio =42.65 P<0.001

Notes:

a B-value indicates regression coefficient of the independent variable;

b t-value indicates t-statistic value;

c variables were not included in the model due to statistical insignificance.

Abbreviations: T2DM, diabetes mellitus type 2; BMI, body mass index; STOP, Snoring, Tiredness, Observed apnea, and high blood Pressure; SF-36, Medical Outcomes Study Short Form-36; HbA1c, glycated hemoglobin; ns, not significant.