Level of proinsulin in association with cardiovascular risk factors and sleep snoring

Table 1 Sex distribution of sleep snoring subjects

Snoring	Male		Female		Total
Never	265		481		746
Seldom	34		29		63
Sometimes	83		68		151
Often	59		39		98
Very often	89		46		135
Total	530		663		1 193
Statistical parameter		χ2 = 68.227		P<0.001

Table 2 Age distribution of sleep snoring subjects

Snoring	35~	40~	45~	50~	55~	Total
Never	225	144	143	113	121	746
Seldom	17	5	9	14	18	63
Sometimes	39	18	31	28	35	151
Often	18	13	23	18	26	98
Very often	22	18	25	30	40	135
Total	321	198	231	203	240	1 193
Statistical parameter			χ2 = 44.465	P<0.001

Table 3 Spearman correlation analysis of sleep snoring with tested parameters

Parameters	BMI	WC	SBP	DBP	FBG	CH
Correlation coefficient	0.177b	0.268b	0.211b	0.191b	0.027	0.126b
Parameters	TG	HDL	LDL	TI	PI	RFS
Correlation coefficient	0.132b	-0.04	0.108b	0.05	0.156b	0.194b

^bP<0.01 vs others. Abbreviations: BMI, body mass index; WC, waist circumference; SBP, systolic blood pressure; DBP, diastolic blood pressure; FBG, fasting blood glucose; CH, fasting total cholesterol; TG, fasting triglycerides; HDL, fasting high-density lipoprotein cholesterol; LDL, fasting low-density lipoprotein cholesterol; TI, true insulin; PI, proinsulin; RFS, risk factors score.

Table 4 Analysis of covariate variance with sleep snoring as factor variable, and age and sex as controlling variables

Para- meters	Never	Seldom	Some-times	Often	Very often	F	P
BMI	23.49±2.83	24.08±2.89	24.14±2.84	24.56±3.66	25.32±3.47	16.335	0.000
WC	75.89±7.78	78.68±8.31	78.83±7.89	81.65±9.98	83.37±10.63	22.000	0.000
SBP	121.03±19.05	128.77±21.08	126.39±20.28	126.80±20.29	133.93±23.16	7.169	0.000
DBP	77.25±10.66	79.48±10.75	80.20±11.58	80.68±13.89	85.59±13.59	9.957	0.000
FBG	4.44 (4.06-4.89)	4.40 (4.17-4.80)	4.53 (4.12-4.93)	4.47 (4.08-4.81)	4.53 (4.07-4.88)	0.124	0.974
CH	3.95 (3.39-4.54)	4.25 (3.32-5.01)	4.09 (3.67-4.60)	4.00 (3.49-4.65)	4.34 (3.70-5.04)	2.580	0.007
TG	0.75 (0.55-1.08)	0.77 (0.59-1.22)	0.91 (0.62-1.31)	0.79 (0.61-1.33)	0.89 (0.63-1.59)	5.778	0.000
HDL	1.07 (0.89-1.28)	1.15 (0.93-1.31)	1.02 (0.83-1.23)	1.03 (0.80-1.28)	1.04 (0.83-1.29)	1.693	0.149
LDL	2.44 (2.02-2.85)	2.55 (2.03-3.10)	2.60 (2.19-3.10)	2.53 (2.13-2.96)	2.74 (2.19-3.21)	1.392	0.234
TI	4.81 (2.89-6.98)	4.69 (2.54-7.09)	5.11 (3.55-7.18)	5.13 (2.88-7.50)	5.06 (3.16-7.58)	2.868	0.022
PI	3.26 (1.92-5.11)	3.29 (1.77-5.19)	4.03 (2.46-6.49)	4.19 (2.22-6.09)	4.43 (2.72-7.18)	5.980	0.000
RFS	1.24±1.15	1.47±1.33	1.57±1.27	1.70±1.28	2.06±1.53	11.135	0.000

Abbreviations as in Table 3.

Table 5 Analysis of multivariate logistic regression with sleep snoring as an independent variable

Variable	B	S.E.	WALD	P	OR (95%CI)
Sex	-0.913	0.130	49.133	0.000	0.401 (0.311-0.518)
Age (yr)	0.223	0.044	25.762	0.000	1.249 (1.146-1.361)
Proinsulin	0.199	0.060	10.964	0.001	1.220 (1.085-1.373)
Waist circumference	0.335	0.062	29.504	0.000	1.398 (1.239-1.578)
Constant	-1.150	0.305	14.192	0.000	-

B, SE, and WALD were statistical parameters.