The Relationship between Diabetic Neuropathy and Sleep Apnea Syndrome: A Meta-Analysis

Table 1

Characteristics of studies included in the meta-analysis.

(a)  

Author	Country	Type of diabetes	Age (yrs), mean	BMI (kg/m^2), mean	Duration of diabetes (yrs)	% Men	No. of subject					SA definition	Risk group	Referent group
							Total	DN (+)	DN (+)	DN (−)	DN (−)
								SA (+)	SA (−)	SA (+)	SA (−)
Nomura et al. (2013) [27]	Japan	T2DM	62.8	24.9	11.6	62	261	36	107	28	90	ODI 4% ≥ 5	ODI 4% ≥ 5	ODI 4% < 5
Tahrani et al. (2012) [26]	UK	T2DM	58.0	32.9	10.3	58	234	90	23	61	60	AHI ≥ 5	AHI ≥ 5	AHI < 5
Laaban et al. (2009) [23]	France	T2DM	61.0	31.1	14.4	53	303	90	47	101	65	RDI ≥ 5	RDI ≥ 5	RDI < 5
Takahashi et al. (2003) [24]	Japan	T2DM	58.0	24.4	ND	59	34	14	12	3	5	AHI ≥ 5	AHI ≥ 5	AHI < 5
Ficker et al. (1998) [22]	Germany	T1DM 22	51.3	25.1	17.5	48	22	1	8	0	13	AHI ≥ 10	AHI ≥ 10	AHI < 10
		T2DM 26					26	5	9	0	12

(b)  

Author	Neuropathy definition			Matched age and sex	Matched obesity
	Autonomic	Peripheral	Evaluation of diabetic neuropathy
Nomura et al. (2013) [27]	No	Yes	DTR, vibration, dysesthesia	Yes	Yes
Tahrani et al. (2012) [26]	No	Yes	MNSI examinations scores, MNSI questionnaire scores	Yes	Yes
Laaban et al. (2009) [23]	No	Yes	Patient's records	No	No
Takahashi et al. (2003) [24]	No	No	Not described	No	No
Ficker et al. (1998) [22]	Yes	No	CV, RMSSD, E-I difference, 𝐸/𝐼 ratio, maximum/minimum 30 : 15 ratio	No	No

Abbreviations: AHI: apnea hypoxia index; BMI: body mass index; CV: coefficient of variation; DM: diabetes mellitus; DN: diabetic neuropathy, DTR: deep tendon reflexes; MNSI: Michigan neuropathy screening instrument; ODI: oxygen desaturation index; RMSSD: root mean square of successive difference; RDI: respiratory disturbance index; SA: sleep apnea; T1DM: type 1 diabetes mellitus; T2DM: type 2 diabetes mellitus.