Prevalence of vitamin D deficiency in exclusively breastfed infants at Charoenkrung Pracharak Hospital

Table 1 Demographic data of infants and mothers (df = 2), n (%)

Parametric	Vitamin D deficiency (n = 39)	Vitamin D insufficiency (n = 36)	Vitamin D sufficiency (n = 34)	P value
Prevalence, %	35.78	33.03	31.19	0.326
Season of study				0.523
Summer	11 (28.20)	16 (44.44)	16 (47.05)
Monsoon	15 (38.46)	10 (27.78)	12 (35.29)
Winter	13 (33.33)	10 (27.78)	6 (17.65)
Sun index (median – range)	1.7-9.04	1.37-5.47	1.44-10.95	0.053
Demographic data of infants
Gender				0.053
Male	27 (69.2)	19 (52.8)	14 (41.2)
Female	12 (30.8)	17 (47.2)	20 (58.8)
Weight (g)	6956.92 ± 762.92	6880.28 ± 1036.99	6657.53 ± 540.74	0.008
Length (cm)	62.28 ± 1.81	62.03 ± 2.24	61.15 ± 2	0.105
Gestational age (wk)	38.62 ± 1.09	38.64 ± 1.1	38.68 ± 1	0.930
Birth weight (g)	3110.51 ± 338.45	3093.92 ± 345.04	3332.5 ± 362.05	0.008
Birth length (cm)	51.38 ± 2.09	51.33 ± 1.67	51.35 ± 2.04	0.105
Demographic data of mothers
Age (yr)	29.56 ± 7.18	27.69 ± 6.6	29.10 ± 6.9	0.496
Age intervals				0.754
10-19 (yr)	5 (12.8)	4 (11.1)	3 (8.8)
19-35 (yr)	26 (66.7)	26 (72.2)	21 (61.8)
≥ 35 (yr)	8 (20.5)	6 (16.7)	10 (29.4)
Body weight (kg)	60.03 ± 11.61	57.39 ± 9.27	57.39 ± 9.25	0.496
Height (cm)	158.24 ± 5.73	158.83 ± 5.39	160.54 ± 6.25	0.274
BMI (kg/m2)	23.95 ± 4.4	22.76 ± 3.54	22.48 ± 3.87	0.251
Obesity	9 (26.5)	8 (22.2)	10 (25.6)	0.908
Education				0.678
Elementary school	3 (8.8)	2 (5.6)	3 (7.9)
Junior High School	10 (29.4)	6 (16.7)	6 (15.8)
High School	13 (38.2)	16 (44.4)	14 (36.8)
Bachelor degree or above	8 (23.5)	12 (33.3)	15 (39.5)
Family income (Dollars per month)	973.09 ± 719.64	890.97 ± 511.1	1061.92 ± 1445.85	0.777
Poverty	17 (43.58)	13 (36.11)	16 (47.05)	0.635
Not poverty	22 (56.41)	23 (63.88)	18 (52.94)
Vitamin D supplement				0.001
No	29 (74.35)	23 (63.88)	10 (32.30)
Yes	10 (25.64)	11 (30)	21 (67.70)

Poverty is defined as having a monthly income of less than 600 dollars. BMI: Body mass index.

Table 2 Factors associated with hypovitaminosis D (vitamin D deficiency and vitamin D insufficiency) by univariate logistic regression and multivariate analysis (df = 1)

Univariate analysis	Hypovitaminosis D	Sufficiency	P value	Crude OR (95%CI)
Parametric
Infants
Male, n	27	33	0.028	2.52 (1.1-5.76)
Birth weight (kg)	3.11 ± 0.34	3.21 ± 0.37	0.170	0.46 (0.15-1.4)
Sun index (h/wk)	2.28 ± 2.14	1.84 ± 1.83	0.355	1.12 (0.89-1.39)
Mothers
Vitamin D supplement, n	10	32	0.020	0.36 (0.15-0.85)
Multivariate analysis
Parametric
Infants
Male, n			0.511	1.46 (0.47-4.49)
Birth weight (kg)			0.004	0.08 (0.01-0.45)
Mothers
Vitamin D supplement, n			0.109	1.28 (0.95-1.73)