The association between socioeconomic status and visual impairments among primary glaucoma: the results from Nationwide Korean National Health Insurance Cohort from 2004 to 2013

Table 2 Demographic characteristics based on the presence of visual impairment

Variable	Not impaired			Impairment Diagnosed				TOTAL
				BEFORE Glaucoma		AFTER Glaucoma
	N	%	N	N	%	N	%	N	P-value
Age group
~ 39	292	94.2	18	8	2.6	10	3.2	310	0.013
40 ~ 49	217	93.5	15	12	5.2	3	1.3	232
50 ~ 59	357	93.9	23	17	4.5	6	1.6	380
60 ~ 69	390	90.5	41	31	7.2	10	2.3	431
70~	330	88.0	45	33	8.8	12	3.2	375
Sex
Male	803	89.8	91	66	7.4	25	2.8	894	0.008
Female	783	93.9	51	35	4.2	16	1.9	834
Income group
High	850	94.2	52	33	3.7	19	2.1	902	<0.001
Middle	441	90.0	49	33	6.7	16	3.3	490
Low	295	87.8	41	35	10.4	6	1.8	336
Residential Area
Urban	1219	93.6	83	73	5.6	10	0.8	1302	0.568
Rural	367	92.9	28	73	18.5	10	2.5	395
Hospital Level
General hospital	796	91.9	70	46	5.3	24	2.8	866	0.612
Hospital	129	91.5	12	8	5.7	4	2.8	141
Clinic	661	91.7	60	47	6.5	13	1.8	721
Insurance Type
NHI, self-employees	456	92.1	39	30	6.1	9	1.8	495	0.011
NHI, employees	1077	92.1	92	61	5.2	31	2.7	1169
Medical Aid	53	82.8	11	10	15.6	1	1.6	64
Hypertension
Normal	876	93.0	66	44	4.7	22	2.3	942	0.073
Hypertension	710	90.3	76	57	7.3	19	2.4	786
Diabetes
Normal	1243	92.7	98	65	4.8	33	2.5	1341	<0.001
Mild Diabetes	231	90.6	24	24	9.4	-	0.0	255
Complications	112	84.8	20	12	9.1	8	6.1	132
Refractory errors
No	672	93.2	49	37	5.1	12	1.7	721	0.138
Yes	914	90.8	93	64	6.4	29	2.9	1007
Cataract
No	839	95.1	43	26	2.9	17	1.9	882	0.073
Yes	747	88.3	99	75	8.9	24	2.8	846
CCI^a	2.81	±2.25		3.10	±2.76	2.27	±2.54
Total	1586	91.8	142	101	5.8	41	2.4	1728

ISSN: 1471-2415