Medical travel patterns for hepatocellular carcinoma treatment in South Korea: National Health Insurance data from 2013 to 2021

Table 1 Patient characteristics according to treatment regions

Characteristics	Different region		Residential region		P value
	n/N	%	n/N	%
Age in years
0-39	1258/1938	64.9	680/1938	35.1	< 0.0001a
40-49	5033/8745	57.6	3712/8745	42.4
50-59	11491/21062	54.6	9571/21062	45.4
60-69	9759/18575	52.5	8816/18575	47.5
70-79	5563/11775	47.2	6212/11775	52.8
≥ 80	1053/2713	38.8	1660/2713	61.2
Sex
Male	26852/50988	52.7	24136/50988	47.3	0.6841
Female	7305/13820	52.9	6515/13820	47.1
Residential region
Seoul	401/9879	4.1	9478/9879	95.9	< 0.0001b
Busan	1923/4777	40.3	2854/4777	59.7
Daegu	758/2780	27.3	2022/2780	72.7
Incheon	1392/3185	43.7	1793/3185	56.3
Gwangju	915/1194	76.6	279/1194	23.4
Daejeon	529/1212	43.6	683/1212	56.4
Ulsan	509/999	51.0	490/999	49.0
Chungcheong	4159/5122	81.2	963/5122	18.8
Gyeonggi	8909/15978	55.8	7069/15978	44.2
Gangwon	1552/2299	67.5	747/2299	32.5
Jeolla	4097/6194	66.1	2097/6194	33.9
Gyeongsang	8279/10042	82.4	1763/10042	17.6
Jeju	726/1147	63.3	421/1147	36.7
Year of diagnosis
2013	4008/7552	53.1	3544/7552	46.9	0.0045b
2014	3986/7382	54.0	3396/7382	46.0
2015	4047/7501	54.0	3454/7501	46.0
2016	3933/7436	52.9	3503/7436	47.1
2017	3894/7404	52.6	3510/7404	47.4
2018	3817/7204	53.0	3387/7204	47.0
2019	3775/7294	51.8	3519/7294	48.2
2020	3530/6872	51.4	3342/6872	48.6
2021	3167/6163	51.4	2996/6163	48.6
CCI
2	4063/7285	55.8	3222/7285	44.2	< 0.0001b
3-4	14207/26245	54.1	12038/26245	45.9
≥ 5	15887/31278	50.8	15391/31278	49.2
Income level, quintiles
Medicare	1450/3847	37.7	2397/3847	62.3	< 0.0001b
1 (low income)	5716/11297	50.6	5581/11297	49.4
2	4747/9474	50.1	4727/9474	49.9
3	5885/11406	51.6	5521/11406	48.4
4	7155/13047	54.8	5892/13047	45.2
5 (high income)	9204/15737	58.5	6533/15737	41.5
Liver cirrhosis
Yes	5611/11054	50.8	5443/11054	49.2	< 0.0001b
No	28546/53754	53.1	25208/53754	46.9
Extrahepatic metastasis
Yes	3912/7458	52.5	3546/7458	47.5	0.6442
No	30245/57350	52.7	27105/57350	47.3

^aP < 0.05 from t-test for continuous variables.

^bP < 0.05 from χ² test for categorical variables.

CCI: Charlson comorbidity index.

Table 2 Factors affecting initial treatment at hospitals outside of residential regions

Factors	aOR	95%CI
		Low	High
Age in years
00-39	Reference
40-49	0.733	0.661	0.812
50-59	0.649	0.589	0.715
60-69	0.598	0.542	0.659
70-79	0.484	0.438	0.535
≥ 80	0.343	0.304	0.387
Sex
Male	Reference
Female	1.008	0.971	1.047
Residential regions
Seoul	Reference
Busan	15.926	14.189	17.875
Daegu	8.861	7.779	10.093
Incheon	18.344	16.236	20.725
Gwangju	77.516	65.581	91.622
Daejeon	18.307	15.737	21.295
Ulsan	24.560	20.935	28.812
Chungcheong	102.079	90.350	115.330
Gyeonggi	29.790	26.829	33.078
Gangwon	49.107	43.005	56.074
Jeolla	46.179	41.247	51.700
Gyeongsang	110.994	99.196	124.194
Jeju	40.759	34.865	47.650
Year of diagnosis
2013	Reference
2014	1.038	0.973	1.107
2015	1.036	0.972	1.105
2016	0.993	0.931	1.059
2017	0.981	0.920	1.046
2018	0.996	0.934	1.063
2019	0.949	0.889	1.012
2020	0.934	0.875	0.997
2021	0.935	0.874	1.000
CCI
1-2	Reference
3-4	0.936	0.888	0.986
≥ 5	0.819	0.778	0.862
Income level, quintiles
Medicare	Reference
1 (low income)	1.693	1.571	1.825
2	1.66	1.537	1.793
3	1.762	1.635	1.899
4	2.007	1.864	2.161
5 (high income)	2.329	2.166	2.504
Liver cirrhosis
Yes	Reference
No	1.099	1.055	1.145
Extrahepatic metastasis
Yes	Reference
No	1.011	0.964	1.062

aOR: Adjusted odds ratio; CCI: Charlson comorbidity index; CI: Confidence interval.