Table 1. Demographic profiles of patients with hyponatremia, divided into severe and non-severe hyponatremia.

	Hyponatremia
	Severe		Non-Severe		All		Comparison
	N = 572		N = 4328		N = 4900		N = 19545
	n	%	n	%	n	%	n	%	p-value1	p-value2
Age, year									0.89	< 0.0001
< 65	136	23.8	1661	38.4	1797	36.7	7188	36.8
≥ 65	436	76.2	2667	61.6	3103	63.3	12357	63.2
Mean (SD)	72.1 (13.5)		66.7 (16.5)		67.1 (16.2)		67.3 (16.3)		0.32†	< 0.0001#
Gender									0.90	0.94
Women	260	45.5	1935	44.7	2195	44.8	8736	44.7
Men	312	54.5	2393	55.3	2705	55.2	10809	55.3
Comorbidity
Diabetes	237	41.4	1761	40.7	1998	40.8	4206	21.5	< 0.0001	< 0.0001
Hypertension	436	76.2	2918	67.4	3354	68.4	10313	52.8	< 0.0001	< 0.0001
Hyperlipidemia	179	31.3	1432	33.1	1611	32.9	5389	27.6	< 0.0001	< 0.0001
Ischemic heart disease	269	47.0	1699	39.3	1968	40.2	5854	30.0	< 0.0001	< 0.0001
Heart failure	121	21.2	716	16.5	837	17.1	1572	8.04	< 0.0001	< 0.0001
Mental illness	299	52.3	2003	46.3	2302	47.0	6797	34.8	< 0.0001	< 0.0001
Stroke	324	56.6	1621	37.5	1945	39.7	3954	20.2	< 0.0001	< 0.0001
Liver cirrhosis	50	8.74	358	8.27	408	8.33	358	1.83	< 0.0001	< 0.0001
Atrial fibrillation	58	10.1	264	6.10	322	6.57	513	2.62	< 0.0001	< 0.0001
CKD	50	8.74	353	8.16	403	8.22	594	3.04	< 0.0001	< 0.0001
Parkinsonism	47	8.22	222	5.13	269	5.49	417	2.13	< 0.0001	< 0.0001
Cancer
Brain	3	0.52	9	0.21	12	0.24	3	0.02	< 0.0001	< 0.0001
Non-brain	98	17.1	606	14.0	704	14.4	870	4.45	< 0.0001	< 0.0001
Diuretics
Furosemide	277	48.4	1701	39.3	1978	40.4	3398	17.4	< 0.0001	< 0.0001
Thiazide	57	10.0	221	5.11	278	5.67	669	3.42	< 0.0001	< 0.0001
Others	57	10.0	244	5.64	301	6.14	400	2.05	< 0.0001	< 0.0001
Follow-up years
Mean (SD)	2.16 (2.53)		3.20 (2.91)		3.10 (2.89)		5.16 (2.81)		< 0.0001†	< 0.0001#

SD, standard deviation; Chi-square

^†t-test

^#ANOVA. p-value

¹: the p-value between all hyponatremia and comparison groups. p-value

²: the p-value for different types of dysnatremia relative to that for the comparison group