Prevalence of vitamin D deficiency in Korea: Results from KNHANES 2010 to 2011

In Kyung Jung

doi:10.4163/jnh.2013.46.6.540

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Jung: Prevalence of vitamin D deficiency in Korea: Results from KNHANES 2010 to 2011

Original Article

J Nutr Health 2013;46(6):540-551.

Published online: 10 January 2013

DOI: https://doi.org/10.4163/jnh.2013.46.6.540

Prevalence of vitamin D deficiency in Korea: Results from KNHANES 2010 to 2011

In Kyung Jung^§

Department of Beauty Art, Honam University, Gwangju 502–791, Korea

^§ To whom correspondence should be addressed. E-mail: jungik@honam.ac.kr

Received 23 September 2013 Revised 18 November 2013 Accepted 20 November 2013

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

Vitamin D deficiency (VDD) is becoming an epidemic and thereby a global health problem. Further, VDD adversely affects calcium metabolism and skeletal health, and is associated with increased risk of several diseases, e.g., autoimmune diseases, several types of cancers, type 2 diabetes mellitus, cardiovascular diseases, infectious diseases, asthma, psoriatic arthritis, and etc. To evaluate the prevalence of VDD in Korea, and then to evaluate the association of several factors with serum 25(OH)D level, the author analyzed the data of 14,456 individuals who were 10 years of age and over from the Fifth Korea National Health and Nutrition Examination Survey 1 & 2 (KNHANES V-1 & 2) conducted by the Korean Centers for Disease Control & Prevention. As a result, among Koreans (age ≧ 10years), 65.9% of males and 77.7% of females were below optimum blood serum 25(OH)D (20 ng/mL). VDD is more severe in female than in male at all age groups. In addition, the younger generations had less 25(OH)D level than older generations in Korea. The analysis by complex sample general linear model (CSGLM) suggested that blood 25(OH)D concentration was related with gender (p ＜ .001), residence (p = .030), occupation (p ＜ .001), anemia (p ＜ .001) and physical activity (p ＜ .001). In conclusion, VDD is pandemic and it is more severe in younger generations in Korea. Further, from the results by CSGLM, serum 25(OH)D status is closely related with the life style of Koreans. (J Nutr Health 2013; 46(6): 540 – 551)

Keywords: vitamin D, VDD, 25(OH)D, life style, KNHANES.

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Table 1.

General characteristics for participants of KNHANES 2010–2011 (age ≥ 10 years)

Parameter		Total		Male		Female
Parameter		Estimated %	Unweighted frequency	Estimated %	Unweighted frequency	Estimated %	Unweighted frequency
Age, yrs	10–19	14.7%	2,011	15.6%	1,057	13.9%	954
	20–29	15.4%	1,345	16.1%	553	14.7%	792
	30–39	18.1%	2,386	18.6%	990	17.6%	1,396
	40–49	18.9%	2,272	19.3%	1,013	18.6%	1,259
	50–59	15.4%	2,397	15.5%	1,010	15.4%	1,387
	60–69	9.1%	2,092	8.7%	952	9.5%	1,140
	70–79	6.4%	1,578	5.1%	692	7.6%	886
	80 ≤	1.9%	375	1.2%	135	2.5%	240
	Age-total	100.0%	14,456	100.0%	6,402	100.0%	8,054
Region	Dong	79.8%	11,525	80.0%	5,109	79.5%	6,416
	Town-village	20.2%	2,931	20.0%	1,293	20.5%	1,638
	Region-total	100.0%	14,456	100.0%	6,402	100.0%	8,054
Housing	General house	68.2%	7,568	68.0%	3,370	68.4%	4,198
	Apartment	31.8%	6,888	32.0%	3,032	31.6%	3,856
	Housing-total	100.0%	14,456	100.0%	6,402	100.0%	8,054
Household income	Poor	17.0%	2,753	15.1%	1,116	18.9%	1,637
	Fair-poor	27.9%	3,671	27.5%	1,625	28.3%	2,046
	Fair-rich	28.9%	3,981	30.1%	1,817	27.7%	2,164
	Rich	26.2%	3,856	27.3%	1,761	25.1%	2,095
	Houshold income-total	100.0%	14,261	100.0%	6,319	100.0%	7,942
Occupation	Administrators & specialists	13.0%	1,535	15.9%	848	10.2%	687
	Clecks	8.6%	980	10.2%	557	6.9%	423
	Service workers & marketers	13.6%	1,549	12.9%	621	14.3%	928
	Agriculture, forestry & fishery	6.5%	1,029	8.0%	572	5.1%	457
	Engineers, technicians & assemblers	11.1%	1,153	19.7%	975	2.6%	178
	Manual laborers	8.0%	1,052	6.8%	406	9.2%	646
	Homemakers & students	39.1%	5,644	26.4%	1,617	51.7%	4,027
	Occupation-total	100.0%	12,942	100.0%	5,596	100.0%	7,346
Anemia	No	92.5%	12,306	97.6%	5,783	87.3%	6,523
	Yes	7.5%	1,137	2.4%	209	12.7%	928
	Anemia-total	100.0%	13,443	100.0%	5,992	100.0%	7,451
BMI, kg/m 2	＜18.5	8.3%	1,213	6.7%	483	10.0%	730
	18.5 to ＜23	41.4%	5,914	37.0%	2,366	45.7%	3,548
	23 to ＜25	21.4%	3,061	23.8%	1,498	19.0%	1,563
	25 to ＜30	24.9%	3,625	28.9%	1,807	20.9%	1,818
	30 ≤	4.0%	499	3.6%	179	4.3%	320
	BMI-total	100.0%	14,312	100.0%	6,333	100.0%	7,979
Walking	Yes	39.2%	4,662	41.7%	2,154	36.8%	2,508
	No	60.8%	7,598	58.3%	3,102	63.2%	4,496
	Walking-total	100.0%	12,260	100.0%	5,256	100.0%	7,004
Physical activity	No	82.6%	9,868	80.1%	4,089	84.9%	5,779
	Medium	6.1%	759	5.8%	290	6.4%	469
	High	11.3%	1,215	14.1%	643	8.7%	572
	Physical activity-total	100.0%	11,842	100.0%	5,022	100.0%	6,820
25(OH) D, ng/mL	Deficient (＜10)	7.3%	973	5.1%	268	9.7%	705
	Insufficient (10 to ＜20)	64.4%	8,553	60.8%	3,537	68.0%	5,016
	Optimal (20 ≤)	28.3%	3,993	34.2%	2,216	22.4%	1,777
	25(OH) D-total	100.0%	13,519	100.0%	6,021	100.0%	7,498

Table 2.

25(OH) D concentration by several parameters in males (age ≥ 10 years)

Parameter		Subgroups	25(OH) D, ng/mL				25(OH) D status, EF (Std. E.)%			χ²	p
			Estimated mean	Std. E.	95% CI		Deficient	Insufficient	Sufficient
			Estimated mean	Std. E.	Lower	Upper	Deficient	Insufficient	Sufficient
Age	10–19		16.95	.257	16.44	17.45	6.8 (1.2)	68.5 (2.0)	24.7 (1.9)	263.587	p ＜ .001
	20–29		16.68	.297	16.10	17.27	5.2 (1.1)	73.6 (2.2)	21.2 (2.2)
	30–39		17.65	.279	17.10	18.20	5.6 (0.9)	65.6 (2.0)	28.9 (2.1)
	40–49		18.68	.290	18.11	19.25	4.6 (0.8)	56.7 (2.2)	38.7 (2.3)
	50–59		19.81	.312	19.20	20.42	4.3 (0.8)	51.3 (2.2)	44.4 (2.2)
	60–69		20.20	.342	19.53	20.88	2.8 (0.7)	50.7 (2.4)	46.5 (2.4)
	70–79		20.51	.443	19.64	21.38	5.6 (1.4)	45.3 (2.6)	49.1 (2.8)
	80 ≤		20.13	.987	18.19	22.07	5.5 (1.4)	36.4 (5.6)	58.1 (6.1)
		Age-total					5.1 (0.5)	60.8 (1.2)	34.2 (1.3)
Region	Dong		17.66	.178	17.31	18.01	5.7 (0.5)	64.8 (1.1)	29.5 (1.2)	238.221	p ＜ .001
	Town-village		20.99	.529	19.95	22.03	2.4 (0.7)	44.6 (3.6)	53.0 (3.8)
		Region-total					5.1 (0.5)	60.8 (1.2)	34.2 (1.3)
Housing	General house		18.62	.255	18.12	19.12	5.4 (0.6)	58.2 (1.6)	36.5 (1.7)	036.997	p = .001
	Apartment		17.67	.223	17.23	18.10	4.4 (0.6)	66.3 (1.5)	29.3 (1.7)
		Housing-total					5.1 (0.5)	60.8 (1.2)	34.2 (1.3)
Household income	Poor		18.64	.356	17.94	19.34	7.7 (1.3)	54.1 (2.3)	38.2 (2.6)	039.125	p = .002
	Fair-poor		18.42	.283	17.87	18.98	4.5 (0.7)	60.5 (2.0)	35.0 (2.1)
	Fair-rich		17.85	.242	17.37	18.32	5.3 (0.8)	63.9 (1.8)	30.8 (1.9)
	Rich		18.62	.226	18.18	19.07	3.7 (0.6)	60.9 (1.2)	35.4 (1.8)
		Household income-total					5.0 (0.5)	60.7 (1.2)	34.3 (1.3)
Occupation	Administrators & specialists		17.26	.221	16.83	17.70	5.8 (1.1)	68.3 (2.0)	25.9 (2.0)	361.851	p ＜ .001
	Clecks		17.36	.313	16.74	17.98	4.3 (1.0)	68.1 (2.6)	27.6 (2.6)
	Service workers & marketers		18.01	.291	17.44	18.58	4.0 (0.9)	64.9 (2.2)	31.1 (2.2)
	Agriculture, forestry & fishery		23.48	.600	22.30	24.66	1.2 (0.7)	27.8 (3.0)	71.0 (3.2)
	Engineers, technicians & assemblers		18.89	.318	18.26	19.51	4.3 (0.8)	57.5 (2.3)	38.2 (2.3)
	Manual laborers		18.58	.456	17.68	19.48	4.6 (1.4)	58.3 (3.3)	37.1 (3.4)
	Homemakers & students		17.25	.242	16.77	17.72	8.2 (1.0)	63.9 (1.7)	27.9 (1.7)
		Occupation-total					5.3 (0.5)	60.6 (1.2)	34.2 (1.3)
Anemia	No		18.29	.185	17.92	18.65	4.9 (0.4)	61.4 (1.2)	34.0 (1.3)	011.853	p = .007
	Yes		19.04	.544	17.97	20.11	10.3 (2.8)	50.5 (4.8)	39.2 (4.1)
		Anemia-total					5.0 (0.4)	60.8 (1.2)	34.1 (1.3)
Walking	Yes		18.58	.234	18.12	19.04	4.8 (0.6)	59.2 (1.6)	36.0 (1.7)	000.492	p = .848
	No		18.42	.210	18.00	18.83	5.0 (0.6)	59.9 (1.4)	35.1 (1.5)
		Walking-total					4.9 (0.4)	59.6 (1.3)	35.5 (1.4)
Physical activity	No		18.15	.196	17.77	18.54	5.7 (0.5)	60.8 (1.3)	33.5 (1.4)	043.255	p ＜ .001
	Medium		20.92	.596	19.75	22.10	1.4 (0.7)	50.9 (3.8)	47.7 (3.9)
	High		18.93	.333	18.27	19.58	2.3 (0.7)	59.5 (2.6)	38.2 (2.6)
		Physical activity-total					5.0 (0.5)	60.1 (1.3)	35.0 (1.4)
BMI, kg/m 2	＜18.5		17.63	.490	16.67	18.60	9.6 (2.3)	60.6 (3.3)	29.8 (3.1)	063.421	p ＜ .001
	18.5 to ＜23		18.10	.228	17.65	18.54	5.9 (0.7)	61.4 (1.5)	32.7 (1.6)
	23 to ＜25		18.71	.250	18.22	19.21	4.6 (0.7)	58.3 (1.9)	37.2 (1.9)
	25 to ＜30		18.64	.233	18.18	19.10	3.5 (0.5)	59.9 (1.8)	36.7 (1.8)
	30 ≤		16.73	.411	15.92	17.54	4.2 (1.8)	76.3 (3.7)	19.4 (3.5)
		BMI-total					5.0 (0.5)	60.7 (1.2)	34.3 (1.3)

EF: estimated frequency, Std. E.: standard error, CI: confidence interval

Table 3.

25(OH) D concentration by several parameters in females (age ≥ 10 years)

Parameter		Subgroups	25(OH) D, ng/mL				25(OH) D status, EF (Std. E.)%			χ²	p
			Estimated mean	Std. E.	95% CI		Deficient	Insufficient	Optimum
			Estimated mean	Std. E.	Lower	Upper	Deficient	Insufficient	Optimum
Age	10–19		15.61	.235	15.15	16.07	9.6 (1.2)	74.7 (2.0)	15.7 (1.7)	370.176	p ＜ .001
	20–29		14.47	.251	13.97	14.96	15.1 (1.7)	73.2 (2.0)	11.7 (1.7)
	30–39		15.79	.248	15.30	16.27	11.5 (1.7)	71.6 (1.6)	17.0 (1.6)
	40–49		16.05	.222	15.62	16.49	9.4 (0.9)	70.8 (1.6)	17.0 (1.6)
	50–59		17.92	.262	17.40	18.43	5.9 (0.7)	62.7 (1.8)	31.4 (1.9)
	60–69		18.50	.320	17.87	19.13	6.6 (0.9)	56.6 (2.1)	36.8 (2.2)
	70–79		18.20	.385	17.45	18.96	7.9 (1.3)	57.9 (2.5)	34.3 (2.5)
	80 ≤		18.92	.707	17.53	20.31	6.2 (2.2)	55.6 (5.1)	38.2 (5.4)
		Age-total					9.7 (0.6)	68.0 (1.0)	22.4 (1.1)
Region	Dong		16.09	.175	15.75	16.44	10.4 (0.7)	69.1 (1.1)	20.1 (1.1)	076.985	p ＜ .001
	Town-village		17.85	.451	16.97	18.74	6.5 (1.1)	63.6 (2.6)	30.3 (2.9)
		Region-total					9.7 (0.6)	68.0 (1.0)	22.4 (1.1)
Housing	General house		16.89	.228	16.44	17.34	8.7 (0.8)	66.1 (1.4)	25.2 (1.5)	082.141	p ＜ .001
	Apartment		15.48	.191	15.11	15.86	11.8 (1.0)	72.0 (1.2)	16.3 (1.2)
		Housing-total					9.7 (0.6)	68.0 (1.0)	22.4 (1.1)
Household income	Poor		17.41	.308	16.81	18.02	8.5 (1.0)	61.9 (1.9)	29.7 (2.0)	060.854	p ＜ .001
	Fair-poor		16.44	.231	15.99	16.89	9.9 (0.9)	66.8 (1.6)	23.3 (1.6)
	Fair-rich		16.02	.209	15.61	16.43	10.0 (1.0)	71.0 (1.4)	19.0 (1.3)
	Rich		16.30	.218	15.87	16.73	9.8 (1.0)	70.1 (1.6)	20.1 (1.4)
		Household income-total					9.7 (0.6)	67.9 (1.0)	22.4 (1.1)
Occupation	Administrators & specialists		15.36	.285	14.80	15.92	11.7 (1.7)	73.8 (2.2)	14.5 (1.7)	204.392	p ＜ .001
	Clecks		14.94	.311	14.33	15.55	10.3 (1.8)	77.0 (2.5)	12.7 (2.1)
	Service workers & marketers		16.32	.280	15.77	16.87	9.5 (1.1)	69.0 (2.1)	21.5 (2.0)
	Agriculture, forestry & fishery		20.52	.590	19.36	21.68	3.3 (1.1)	48.5 (3.8)	48.1 (3.8)
	Engineers, technicians & assemblers		s 15.95	.517	14.93	16.96	11.6 (3.0)	67.3 (4.4)	21.2 (3.9)
	Manual laborers		16.94	.329	16.30	17.59	8.8 (1.4)	64.1 (2.4)	27.1 (2.5)
	Homemakers & students		16.45	.185	16.08	16.81	10.5 (0.8)	67.0 (1.2)	22.5 (1.3)
		Occupation-total					10.0 (0.7)	67.5 (1.0)	22.5 (1.1)
Anemia	No		16.58	.173	16.24	16.92	9.1 (0.6)	67.9 (1.0)	23.0 (1.1)	027.584	p ＜ .001
	Yes		15.45	.243	14.97	15.92	13.3 (1.4)	69.5 (1.9)	17.2 (1.6)
		Anemia-total					9.7 (0.6)	68.1 (1.0)	22.3 (1.1)
Walking	Yes		16.76	.227	16.31	17.21	8.6 (0.9)	67.4 (1.5)	24.0 (1.5)	007.135	p = .133
	No		16.39	.181	16.04	16.75	10.6 (0.8)	66.7 (1.1)	22.7 (1.2)
		Walking-total					9.8 (0.7)	67.0 (1.0)	23.2 (1.1)
Physical activity	No		16.35	.173	16.01	16.69	10.6 (0.7)	66.8 (1.1)	22.6 (1.1)	014.766	p = .062
	Medium		17.43	.493	16.46	18.40	6.3 (1.4)	66.8 (3.4)	26.9 (3.4)
	High		17.06	.329	16.42	17.71	7.6 (1.3)	68.3 (2.6)	24.1 (2.5)
		Physical activity-total					10.1 (0.7)	66.9 (1.1)	23.0 (1.1)
BMI, kg/m 2	＜18.5		16.05	.280	15.50	16.60	10.1 (1.5)	69.0 (2.2)	20.9 (2.0)
	18.5 to ＜23		16.18	.181	15.82	16.54	10.5 (0.8)	68.9 (1.2)	20.6 (1.2)	026.351	p = .029
	23 to ＜25		16.86	.255	16.35	17.36	9.4 (1.1)	67.1 (1.6)	23.5 (1.6)
	25 to ＜30		16.91	.237	16.44	17.38	7.6 (0.9)	66.5 (1.7)	25.9 (1.7)
	30 ≤		16.04	.407	15.24	16.84	10.9 (2.4)	66.7 (3.4)	22.4 (3.0)
		BMI-total					9.6 (0.6)	68.0 (1.0)	22.4 (1.1)

EF: estimated frequency, Std. E.: standard error, CI: confidence interval

Table 4.

Model effect analysis by CSGLM ¹⁾

Source	df1	df2	Wald F	Significance
(Correct model)	21	339	29.005	＜.001
(Intercept)	01	359	1,322.310	＜.001
Sex	01	359	121.437	＜.001
Region	01	359	4.760	.030
Housing	01	359	2.716	.100
Household income	03	357	2.435	.065
Occupation	06	354	9.624	＜.001
Anemia	01	359	21.853	＜.001
BMI	04	356	2.119	.078
Physical acitivity	02	358	13.746	＜.001
Walking	01	359	2.041	.154
Age	01	359	150.116	＜.001

¹⁾ Model: vitamin D = (intercept) + sex + residence + housing + household income + occupation + anemia + BMI + physical activity + walking + age

Table 5.

Parameter estimates ¹⁾ by CSGLM

Parameter		Estimates	Standard error	95% confidence interval		Hypothesis test
Parameter		Estimates	Standard error	Lower	Upper	t	df	Significance
(Intercept)		12.4112)	.732	10.971	13.852	16.944	359	＜.001
Sex	Male	1.7032)	.155	1.399	2.007	11.020	359	＜.001
	Female	.0002)
Region	Dong	–1.0432)	.478	–1.983	–.103	–2.182	359	.030
	Town-village	.0002)
Housing	General house	.4882)	.296	–.094	1.070	1.648	359	.100
	Apartment	.0002)
Household income	Poor	–.5902)	.249	–1.079	–.100	–2.370	359	.018
	Fair-poor	–.2712)	.229	–.722	.180	–1.182	359	.238
	Fair-rich	–.4332)	.213	–.853	–.014	–2.030	359	.043
	Rich	.0002)
Occupation	Administrators & specialists	–.3822)	.226	–.828	.063	–1.690	359	.092
	Clerks	–.4252)	.259	–.935	.084	–1.641	359	.102
	Service workers & marketers	.0132)	.221	–.422	.447	.058	359	.954
	Agriculture, forestry & fishery	2.8362)	.482	1.888	3.785	5.883	359	＜.001
	Engineers, technicians & assemblers	.5022)	.267	–.023	1.026	1.880	359	.061
	Manual laborers	–.0352)	.277	–.581	.510	–.128	359	.898
	Homemakers & students	.0002)
Anemia	No	1.0272)	.220	.595	1.459	4.675	359	＜.001
	Yes	.0002)
BMI, kg/m 2	＜18.5	.5322)	.442	–.337	1.401	1.205	359	.229
	18.5 to ＜23	.6562)	.305	.056	1.257	2.149	359	.032
	23 to ＜25	.8412)	.302	.246	1.435	2.780	359	.006
	25 to ＜30	.7272)	.297	.143	1.311	2.450	359	.015
	≥30	.0002)
Physical activity	High	.7602)	.235	.298	1.222	3.236	359	.001
	Mid	1.2102)	.279	.662	1.758	4.340	359	＜.001
	No	.0002)
Walking	No	–.2082)	.146	–.495	.079	–1.428	359	.154
	Yes	.0002)
Age		.0712)	.006	.059	.082	12.252	359	＜.001

¹⁾ Model: 25(OH) D = (intercept) + sex + region + housing + household income + occupation + anemia + BMI + physical activity + walking + age

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