Influenza Vaccination Status in Korean Adult Population in Relation with Socioeconomic and Medical Factors

Gyeong-Ran Byeon; Yang-Im Hur; Jae-Heon Kang; Hyun-Ah Park; Kyoung-Woo Kim; Young-Gyu Cho; Koh-Eun Shin; Bong-Hee Kang

doi:10.15384/kjhp.2016.16.1.20

Korean J Health Promot > Volume 16(1); 2016 > Article

Byeon, Hur, Kang, Park, Kim, Cho, Shin, and Kang: Influenza Vaccination Status in Korean Adult Population in Relation with Socioeconomic and Medical Factors

Original Article

Korean Journal of Health Promotion 2016;16(1):20-31.

Published online: January 20, 2016

DOI: https://doi.org/10.15384/kjhp.2016.16.1.20

Influenza Vaccination Status in Korean Adult Population in Relation with Socioeconomic and Medical Factors

Gyeong-Ran Byeon, Yang-Im Hur, Jae-Heon Kang, Hyun-Ah Park, Kyoung-Woo Kim, Young-Gyu Cho, Koh-Eun Shin, Bong-Hee Kang

Department of Family Medicine, Seoul Paik Hospital, Inje University College of Medicine, Seoul, Korea

Corresponding author: Yang-Im Hur, MD Department of Family Medicine, Seoul Paik Hospital, Inje University College of Medicine, 9 Mareunnae-ro, Jung-gu, Seoul 04551, Korea
Tel: +82-2-2270-0097, Fax: +82-2-2272-0908 E-mail: yangim.hur@gmail.com

Received August 17, 2015 Accepted October 26, 2015

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

ABSTRACT

Background

Influenza causes morbidity and mortality, resulting in the medical and socioeconomic costs. We aimed to analyse whether socioeconomic and medical factors may affect influenza vaccination status divided into 2 groups; one aged 19 to 64 years old and the other aged 65 or over who are eligible for free vaccination.

Methods

The study included 1,412 individuals aged 19 and over who responded to influenza vaccination survey, based on 2013 National Health and Nutrition Examination Survey. Related factors were categorized into socioeconomic factors and medical factors. Univariate analyses were conducted to examine the correlations between vaccination rate and each variables. Multivariate analysis was obtained after adjusting variables which were statistcally significant.

Results

Influenza vaccination rate was significantly different in the population aged 19 to 64 (24.9%) and the population aged 65 or over (80.5%). In the former population, high vaccination rate was associated with healthcare usage (odds ratio [OR]=1.37, 95% confidence interval [CI]=1.03–1.83), underlying chronic diseases (OR=2.21, 95% CI=1.43–3.40), and public assistance recipient households (OR＝2.21, 95% CI=1.03–4.78), while low vaccination rate was correlated with no use of medical check up (OR＝0.70, 95% CI=0.52–0.94) and heavy alcoholics (OR＝0.41, 95% CI=0.24–0.70). In the latter population aged 65 or over, high vaccination rate was associated with healthcare usage (OR＝1.82, 95% CI=1.28–2.59), and underlying malignancies (OR＝ 4.79, 95% CI=1.07–21.54), whereas low vaccination rate was associated with public assistance recipient households (OR＝0.33, 95% CI=0.14–0.76), and no use of medical check up (OR＝0.37, 95% CI=0.19–0.73).

Conclusions

In the population below 65 years old, vaccination rate would be expected to rise by the recommendation of medical care providers and expanding the coverage of free vaccination. In elderly, individualized care for those who have less access to medical care and high susceptibility is highly recommended.

Keywords: Influenza vaccines, Vaccination, Adult

Figure 1.

Place of influenza vaccination. (A) Aged 19–64 years. (B) Aged ≥ 65 years.

Figure 2.

Timing of influenza vaccination in adults.

Table 1.

Influenza vaccination rates by age

Characteristics	Age 19–64 years (n＝1,073)			Age 65 years (n＝339)
	N,	Vaccinated	P value	N,	Vaccinated	P value
	Weighted%	Weighted		Weighted%	Weighted
		%(S.E.)			%(S.E.)
Total	1,073 (83.8)	24.9 (1.6)		339 (16.2)	80.5 (2.7)
Age group			＜0.001			0.127
＜50	653 (66.3)	21.2 (1.9)
50–64	420 (33.7)	32.3 (2.1)
65–74				228 (62.9)	78.3 (3.1)
≥ 75				111 (37.1)	84.2 (3.3)
Sex			0.004			0.005
Man	453 (50.8)	21.2 (2.2)		149 (42.4)	74.5 (4.0)
Woman	620 (49.2)	28.8 (1.7)		190 (57.6)	84.9 (2.5)
Education			0.086			0.024
Elementary	135 (10.0)	31.9 (4.6)		206 (62.5)	84.5 (3.0)
Middle	115 (10.2)	32.1 (5.4)		53 (16.2)	71.9 (6.1)
High	447 (44.2)	20.9 (2.6)		55 (14.6)	71.9 (4.6)
College	375 (35.6)	25.8 (2.6)		25 (6.7)	82.8 (6.5)
House income^a			0.904			0.140
Low	123 (11.4)	26.1 (3.9)		168 (50.9)	82.1 (2.9)
Middle	602 (55.9)	25.1 (2.0)		139 (40.0)	81.0 (3.4)
High	348 (32.7)	24.2 (2.9)		32 (9.1)	69.5 (7.6)
Town			0.001			0.413
Urban	759 (72.0)	21.9 (1.3)		222 (64.2)	82.2 (3.4)
Rural	314 (28.0)	32.7 (3.0)		117 (35.8)	77.5 (4.5)
Region			0.185			0.537
Mega city^b	484 (49.5)	22.9 (2.1)		151 (44.3)	78.6 (4.3)
The other	589 (50.5)	26.9 (2.2)		188 (55.7)	82.1 (3.5)
Public assistance recipient households			0.067			0.112
Yes	15 (1.5)	38.9 (8.3)		29 (10.0)	73.6 (4.2)
No	1,058 (98.5)	24.7 (1.6)		309 (90.0)	81.2 (2.9)
Marital status			＜0.001			0.127
Married/unmarried couple living together	792 (68.6)	29.4 (1.6)		226 (62.8)	77.2 (3.7)
Divorced/widowed/separated/never married	281 (31.4)	15.0 (2.7)		113 (37.2)	86.2 (3.8)
Private health insurance			0.450			0.553
Yes	923 (86.4)	25.7 (1.5)		98 (70.3)	77.9 (5.3)
No	141 (13.6)	22.0 (4.7)		237 (29.7)	81.2 (2.9)
Perception on my health			0.394			0.017
Good	358 (34.0)	22.7 (2.0)		61 (15.2)	69.8 (5.4)
Moderate	556 (52.0)	26.3 (2.0)		166 (52.1)	80.5 (2.7)
Poor	158 (14.0)	25.2 (3.5)		112 (32.7)	85.5 (3.6)
Medical check up^c			0.001			0.011
Yes	708 (63.4)	28.6 (1.5)		215 (61.9)	85.1 (2.8)
No	365 (36.6)	18.5 (2.4)		124 (38.1)	72.5 (4.5)
Limited social or physical activity^d			0.049			0.119
Yes	64 (5.1)	35.2 (5.8)		67 (21.5)	85.1 (3.3)
No	1,009 (94.9)	24.4 (1.6)		272 (78.5)	79.2 (3.0)
Health care usage^e			0.001			＜0.001
Yes	508 (46.7)	29.0 (1.9)		207 (62.5)	85.7 (2.3)
No	565 (53.3)	21.3 (1.8)		132 (37.5)	71.8 (3.8)
Occupation			0.046			0.129
Yes	704 (66.4)	23.0 (1.7)		99 (26.9)	76.1 (3.5)
No	369 (33.6)	28.7 (2.5)		240 (73.1)	82.1 (3.0)
High risk drinking^f			＜0.001			0.905
Yes	136 (13.7)	11.4 (2.7)		11 (2.8)	78.3 (2.8)
No	937 (86.3)	27.1 (1.6)		328 (97.2)	80.5 (2.7)
Smoking			0.005			0.109
Current smoker	233 (25.8)	17.9 (2.4)		34 (9.2)	66.6 (10.1)
Ex smoker	165 (16.2)	24.6 (2.8)		101 (30.0)	80.2 (3.6)
Non smoker	674 (57.9)	28.0 (2.0)		201 (60.8)	82.9 (3.0)
BMI			0.705			0.488
＜25	708 (66.6)	24.1 (1.8)		236 (69.6)	79.7 (2.9)
≥ 25	358 (33.4)	25.4 (2.9)		103 (30.4)	82.4 (3.7)
Chronic disease^g	220 (17.3)	40.0 (3.6)	＜0.001	203 (59.0)	81.1 (2.9)	0.632
Cardiovascular disease^h	32 (2.5)	37.4 (10.8)	0.165	53 (15.0)	85.4 (4.7)	0.279
Pulmonary diseaseⁱ	65 (6.4)	32.2 (4.5)	0.096	39 (12.0)	87.8 (6.1)	0.294
Hepatic disease^j	23 (2.1)	22.6 (6.6)	0.734	9 (2.9)	73.5 (10.9)	0.473
Malignancies	28 (2.3)	46.6 (8.4)	0.013	39 (13.1)	95.9 (2.6)	0.003
Underlying disease^k			＜0.001			0.076
Yes	301 (24.9)	35.8 (2.8)		243 (71.4)	82.4 (2.8)
No	772 (75.1)	21.3 (1.7)		96 (28.6)	75.7 (4.2)

Abbreviations: BMI, body mass index. P-value by Chi-square test.

^aDividing the mean monthly household income into four groups by quartiles and then defined as low (Q1), middle (Q2+Q3), and high (Q4)

^bConsist of residents in Seoul, Pusan, Daegu, Incheon, Gwangju, Daejeon, Ulsan.

^cAssesed by asking respondents if they had health checkups or cancer screening within two years.

^dAssesed by asking respondents if they had a limitation on daily life and social activities as a current health problem or a disability.

^eAssesed by asking respondents if they had a hospitalization within one year, outpatient care within two weeks or using pharmacy within two weeks.

^fMeans consumption of alcohol more than twice a week, each of which should meet more than seven shots at a time in men and more than five shots at a time in women.

^gHypertension, diabetes, and dyslipidemia were asked.

^hStroke, myocardiac infarction, and angina were asked.

ⁱTuberculosis, asthma, and chronic obstructive pulmonary disease were asked.

^jHBV, HCV, and liver cirrhosis were asked.

^kChronic disease, cardiovascular disease, pulmonary disease, hepatic disease, and cancer were asked.

Table 2.

Characteristics associated with influenza vaccination in adults aged 19–64 years

Characteristics	Crude OR	Model 1^a	Model 2^b	Model 3^c
Characteristics	Odds ratio (95% confidence interval)
Age
＜50	1.00	1.00	1.00	1.00
50–64	1.772 (1.353–2.321)	1.605 (1.196–2.153)	1.249 (0.912–1.710)	1.169 (0.829–1.648)
Sex
Man	1.00	1.00	1.00	1.00
Woman	1.501 (1.148–1.962)	1.446 (1.074–1.947)	1.116 (0.771–1.615)	1.093 (0.734–1.629)
Education
Elementary	1.343 (0.804–2.246)	1.055 (0.533–2.090)	0.997 (0.513–1.938)	0.997 (0.513–1.938)
Middle	1.356 (0.767–2.398)	1.302 (0.733–2.310)	1.300 (0.732–2.309)	1.300 (0.732–2.309)
High	0.758 (0.498–1.153)	0.753 (0.491–1.153)	0.753 (0.491–1.154)	0.753 (0.491–1.154)
College	1.00	1.00	1.00	1.00
House income
Low	1.108 (0.649–1.894)	1.198 (0.695–2.065)	1.109 (0.640–1.920)	1.217 (0.679–2.182)
Middle	1.048 (0.706–1.555)	1.055 (0.688–1.618)	1.165 (0.770–1.763)	1.138 (0.744–1.740)
High	1.00	1.00	1.00	1.00
Town
Urban	1.00	1.00	1.00	1.00
Rural	1.739 (1.275–2.372)	1.670 (1.137–2.451)	1.678 (1.218–2.313)	1.666 (1.162–2.390)
Region
Mega city	1.00	1.00	1.00	1.00
The other	1.237 (0.898–1.703)	0.971 (0.676–1.394)	1.237 (0.907–1.688)	0.997 (0.726–1.368)
Public assistance recipient households
Yes	1.939 (0.939–4.002)	2.214 (1.025–4.781)	1.502 (0.619–3.649)	1.734 (0.737–4.077)
No	1.00	1.00	1.00	1.00
Marital status
Married/unmarried couple living together	1.00	1.00	1.00	1.00
Divorced/widowed/separated/never married	0.423 (0.275–0.649)	0.495 (0.321–0.764)	0.496 (0.330–0.745)	0.510 (0.339–0.768)
Private health insurance
Yes	1.00	1.00	1.00	1.00
No	0.816 (0.474–1.405)	0.937 (0.518–1.694)	0.806 (0.465–1.397)	0.886 (0.486–1.614)
Perception on my health
Good	1.00	1.00	1.00	1.00
Moderate	1.215 (0.905–1.632)	1.095 (0.822–1.459)	1.052 (0.771–1.434)	1.032 (0.753–1.414)
Poor	1.148 (0.763–1.729)	1.013 (0.646–1.587)	0.772 (0.480–1.242)	0.806 (0.469–1.386)
Medical check up
Yes	1.00	1.00	1.00	1.00
No	0.568 (0.420–0.767)	0.699 (0.524–0.932)	0.594 (0.437–0.807)	0.695 (0.515–0.940)
Limited social or physical activity
Yes	1.687 (0.998–2.853)	1.534 (0.885–2.658)	1.137 (0.632–2.046)	1.176 (0.649–2.133)
No	1.00	1.00	1.00	1.00
Health care usage
Yes	1.513 (1.203–1.904)	1.360 (1.050–1.762)	1.429 (1.103–1.851)	1.371 (1.029–1.827)
No	1.00	1.00	1.00	1.00
Occupation
Yes	1.00	1.00	1.00	1.00
No	1.345 (1.006–1.798)	1.436 (1.046–1.973)	1.272 (0.942–1.717)	1.386 (1.014–1.895)
High risk drinking
Yes	0.347 (0.208–0.580)	0.365 (0.225–0.592)	0.420 (0.238–0.741)	0.406 (0.237–0.696)
No	1.00	1.00	1.00	1.00
Smoking
Current smoker	0.560 (0.378–0.829)	0.619 (0.380–1.007)	0.735 (0.426–1.269)	0.719 (0.410–1.260)
Ex smoker	0.836 (0.603–1.161)	0.812 (0.533–1.237)	0.890 (0.541–1.465)	0.837 (0.536–1.3307)
Non smoker	1.00	1.00	1.00	1.00
BMI
＜25	1.00	1.00	1.00	1.00
≥ 25	1.074 (0.735–1.569)	1.031 (0.681–1.561)	1.065 (0.695–1.631)	1.051 (0.694–1.591)
Chronic disease	2.402 (1.704–3.385)	2.166 (1.424–3.294)	2.211 (1.438–3.401)	2.208 (1.434–3.399)
Cardiovascular disease	1.832 (0.759–4.420)	1.503 (0.624–3.620)	1.223 (0.439–3.411)	1.137 (0.452–2.863)
Pulmonary disease	1.469 (0.928–2.325)	1.376 (0.838–2.261)	1.240 (0.771–1.992)	1.260 (0.734–2.164)
Hepatic disease	0.880 (0.410–1.887)	0.929 (0.447–1.934)	0.788 (0.360–1.723)	0.858 (0.410–1.796)
Malignancies	2.709 (1.222–6.004)	2.279 (1.031–5.041)	2.338 (1.039–5.258)	2.334 (0.988–5.514)
Underlying disease
Yes	2.058 (1.518–2.789)	1.860 (1.345–2.572)	1.789 (1.264–2.532)	1.799 (1.251–2.587)
No	1.00	1.00	1.00	1.00

Abbreviations: OR, odds ratio; BMI, body mass index. P-value＜0.05 by logistic regression analysis.

^aAdjusted by age, sex, education, house income, town, marital status.

^bAdjusted by age, sex, perceived health status, medical check up, health care utilization, high risk drinking, smoking, disease.

^cAdjusted by age, sex, education, house income, town, marital status, perceived health status, medical check up, health care utilization, high risk drinking, smoking, disease.

Table 3.

Characteristics associated with influenza vaccination in adults aged ≥ 65 years

Characteristics	Crude OR	Model 1^a	Model 2^b	Model 3^c
Characteristics	Odds ratio (95% confidence interval)
Age
65–74	1.00	1.00	1.00	1.00
≥ 75	1.472 (0.885–2.448)	1.311 (0.755–2.278)	1.621 (1.020–2.575)	1.482 (0.865–2.540)
Sex
Man	1.00	1.00	1.00	1.00
Woman	1.923 (1.218–3.034)	1.537 (0.917–2.576)	1.754 (0.551–5.587)	1.250 (0.388–4.026)
Education
Elementary	1.134 (0.397–3.245)	0.807 (0.245–2.659)	1.045 (0.250–4.373)	1.017 (0.195–5.309)
Middle school	0.533 (0.171–1.660)	0.445 (0.148–1.340)	0.615 (0.138–2.715)	0.588 (0.131–2.630)
High school	0.533 (0.160–1.770)	0.464 (0.136–1.583)	0.643 (0.137–3.006)	0.589 (0.120–2.885)
College	1.00	1.00	1.00	1.00
House income
Low	2.009 (0.947–4.265)	1.717 (0.798–3.693)	1.581 (0.749–3.335)	1.416 (0.624–3.211)
Middle	1.864 (0.849–4.089)	2.030 (0.968–4.257)	1.956 (0.872–4.384)	1.983 (0.937–4.197)
High	1.00	1.00	1.00	1.00
Town
Urban	1.00	1.00	1.00	1.00
Rural	0.748 (0.366–1.528)	0.708 (0.338–1.480)	0.823 (0.411–1.649)	0.786 (0.376–1.642)
Region
Mega city	1.00	1.00	1.00	1.00
The other	1.248 (0.605–2.574)	1.625 (0.621–4.253)	1.294 (0.647–2.590)	1.887 (0.651–5.469)
Public assistance recipient households
Yes	0.643 (0.358–1.157)	0.410 (0.181–0.928)	0.454 (0.236–0.872)	0.330 (0.144–0.756)
No	1.00	1.00	1.00	1.00
Marital status
Married/unmarried couple living together	1.00	1.00	1.00	1.00
Divorced/widowed/separated/never married	1.843 (0.821–4.140)	1.354 (0.571–3.212)	1.543 (0.678–3.516)	1.530 (0.680–3.441)
Private health insurance
Yes	1.00	1.00	1.00	1.00
No	1.222 (0.617–2.423)	1.049 (0.508–2.163)	1.214 (0.582–2.533)	1.135 (0.492–2.614)
Perception on my health
Good	1.00	1.00	1.00	1.00
Moderate	1.793 (1.107–2.904)	1.601 (0.900–2.847)	1.563 (0.930–2.627)	1.562 (0.896–2.724)
Poor	2.548 (1.433–4.531)	2.165 (1.084–4.325)	2.084 (1.013–4.290)	1.998 (0.936–4.265)
Medical check up
Yes	1.00	1.00	1.00	1.00
No	0.460 (0.254–0.834)	0.363 (0.187–0.703)	0.377 (0.197–0.723)	0.372 (0.189–0.734)
Limited social or physical activity
Yes	1.500 (0.893–2.519)	1.579 (0.867–2.876)	1.054 (0.566–1.964)	1.046 (0.513–2.135)
No	1.00	1.00	1.00	1.00
Health care usage
Yes	2.350 (1.625–3.400)	2.160 (1.516–3.078)	1.820 (1.276–2.596)	1.824 (1.284–2.593)
No	1.00	1.00	1.00	1.00
Occupation
Yes	1.00	1.00	1.00	1.00
No	1.448 (0.893–2.348)	1.078 (0.576–2.017)	0.924 (0.481–1.775)	0.861 (0.419–1.772)
High risk drinking
Yes	0.921 (0.228–3.714)	1.349 (0.369–4.936)	1.449 (0.354–5.931)	1.417 (0.397–5.054)
No	1.00	1.00	1.00	1.00
Smoking
Current smoker	0.412 (0.163–1.043)	0.690 (0.142–3.349)	0.898 (0.188–4.287)	0.766 (0.161–3.647)
Ex smoker	0.873 (0.490–1.431)	1.380 (0.520–3.659)	1.438 (0.539–3.841)	1.254 (0.472–3.329)
Non smoker	1.00	1.00	1.00	1.00
BMI
＜25	1.00	1.00	1.00	1.00
≥ 25	1.189 (0.719–1.965)	1.140 (0.652–1.992)	1.100 (0.632–1.916)	1.112 (0.626–1.978)
Chronic disease	1.102 (0.728–1.668)	1.054 (0.700–1.586)	0.865 (0.556–1.347)	0.862 (0.556–1.337)
Cardiovascular disease	1.492 (0.704–3.161)	1.541 (0.721–3.292)	1.391 (0.651–2.971)	1.446 (0.687–3.042)-
Pulmonary disease	1.847 (0.564–6.054)	1.803 (0.476–6.831)	1.699 (0.479–6.028)	1.570 (0.384–6.420)
Hepatic disease	0.664 (0.181–2.437)	0.581 (0.146–2.314)	0.668 (0.145–3.078)	0.610 (0.137–2.707)
Malignancies	6.469 (1.404–29.814)	6.022 (1.344–26.985)	5.353 (1.125–25.465)	4.792 (1.066–21.537)
Underlying disease
Yes	1.510 (0.949–2.404)	1.474 (0.934–2.327)	1.295 (0.739–2.271)	1.275 (0.738–2.204)
No	1.00	1.00	1.00	1.00

Abbreviations: OR, odds ratio; BMI, body mass index. P-value＜0.05 by logistic regression analysis.

^aAdjusted by age, sex, education, house income, town, marital status.

^bAdjusted by age, sex, perceived health status, medical check up, health care utilization, high risk drinking, smoking, disease.

^cAdjusted by age, sex, education, house income, town, marital status, perceived health status, medical check up, health care utilization, high ris

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