Association Between Serum 25-Hydroxyvitamin D Concentrations and Chronic Pain: Effects of Drinking Habits

Figures & data

Figure 1 Flow chart of subject recruitment.

Table 1 Subject Characteristics

	Total		Without CP		With CP		p-value
	Mean (n)	SD (%)	Mean (n)	SD (%)	Mean (n)	SD (%)
Male (n, %)	338	46.7	194	45.1	144	49.0	0.306
Age (years)	63.9	10.4	63.3	10.0	64.7	10.8	0.072
Height (cm)	159.1	9.4	158.9	8.8	159.4	10.3	0.538
Weight (kg)	59.2	11.0	59.0	11.1	59.5	10.9	0.617
BMI (kg/m^2)	23.3	3.2	23.3	3.3	23.3	3.2	0.845
CRP (mg/dL)	0.15	0.57	0.12	0.45	0.18	0.71	0.160
Serum 25(OH)D (ng/mL)	24.05	7.90	24.37	8.25	23.58	7.36	0.189
Total energy intake (kcal)	1902.7	581.1	1869.7	553.1	1950.9	617.7	0.065
Protein intake (g/1000kcal)	14.83	3.12	15.04	3.15	14.53	3.06	0.029
Lipid intake (g/1000kcal)	23.52	5.87	23.72	5.61	23.23	6.23	0.266
Carbohydrate intake (g/1000kcal)	55.53	8.29	55.42	8.44	55.68	8.06	0.684
Vitamin D intake (μg/1000kcal)	7.94	5.15	8.25	5.37	7.49	4.78	0.051
Grip strength/body weight (kgf/kg)	0.53	0.12	0.54	0.12	0.52	0.12	0.109
Calf circumference/body weight (cm/kg)	0.58	0.07	0.58	0.07	0.58	0.07	0.288
Osteo sono-assessment index	2.61	0.36	2.62	0.36	2.60	0.36	0.642
Smoking status (n, %)							0.842
Non-smoker	384	53.0	231	53.7	153	52.0
Ex-smoker	213	29.4	123	28.6	90	30.6
Current smoker	127	17.5	76	17.7	51	17.3
Exercise habits (n, %)							0.002
More than 5 days/week	241	33.3	162	37.7	79	26.9
1–4 days/week	145	20.0	89	20.7	56	19.0
No exercise	338	46.7	179	41.6	159	54.1
Analgesics administration (n, %)							0.010
No	688	95.0	416	96.7	272	92.5
Yes	36	5.0	14	3.3	22	7.5
Drinking habits (n, %)							0.049
Non-drinker	389	53.7	244	56.7	145	49.3
Drinker	335	46.3	186	43.3	149	50.7

Notes: p-values were from the Student’s t-test for continuous variables and the chi-squared test for categorical variables; p-values < 0.05 are in bold; Total, n = 724; Without CP, n = 430; With CP, n = 294.

Abbreviations: BMI, body mass index; CRP, C-reactive protein; 25(OH)D, 25-hydroxy vitamin D; CP, chronic pain; SD, standard deviation.

Table 2 Comparison of Characteristics Between CP and Non-CP Subjects According to Drinking Habits

	Non-Drinker				p-value	Drinker				p-value
	Without CP		With CP			Without CP		With CP
	Mean (n)	SD (%)	Mean (n)	SD (%)		Mean (n)	SD (%)	Mean (n)	SD (%)
Male (n, %)	64	26.2	27	18.6	0.087	130	69.9	117	78.5	0.074
Age (years)	64.5	10.3	66.2	10.5	0.109	61.8	9.4	63.3	11.0	0.188
Height (cm)	155.5	8.2	153.8	8.7	0.053	163.3	7.4	164.8	8.8	0.112
Weight (kg)	56.3	10.4	55.3	9.9	0.340	62.6	11.0	63.5	10.3	0.444
BMI (kg/m^2)	23.2	3.3	23.3	3.5	0.737	23.4	3.2	23.3	2.8	0.891
CRP (mg/dL)	0.10	0.19	0.25	0.91	0.050	0.15	0.65	0.12	0.44	0.687
Serum 25(OH)D (ng/mL)	22.35	6.77	21.82	6.40	0.445	27.01	9.24	25.30	7.83	0.072
Total energy intake (kcal)	1759.8	526.1	1829.7	597.1	0.229	2014.0	555.8	2068.8	616.5	0.394
Protein intake (g/1000kcal)	15.25	3.05	15.19	2.68	0.840	14.78	3.26	13.89	3.27	0.014
Lipid intake (g/1000kcal)	24.43	5.43	24.64	5.66	0.720	22.79	5.72	21.86	6.46	0.161
Carbohydrate intake (g/1000kcal)	58.50	7.16	58.71	7.30	0.789	51.39	8.31	52.73	7.68	0.128
Vitamin D intake (μg/1000kcal)	7.96	5.01	7.94	4.52	0.963	8.62	5.80	7.05	5.00	0.009
Grip strength/body weight (kgf/kg)	0.50	0.11	0.47	0.10	0.002	0.58	0.11	0.57	0.12	0.622
Calf circumference/body weight (cm/kg)	0.60	0.07	0.61	0.07	0.372	0.56	0.06	0.55	0.06	0.112
Osteo sono-assessment index	2.55	0.36	2.46	0.30	0.011	2.70	0.34	2.74	0.36	0.298
Smoking status (n, %)					0.182					0.303
Non-smoker	172	70.5	112	77.2		59	31.7	41	27.5
EX-smoker	50	20.5	19	13.1		73	39.2	71	47.7
Current smoker	22	9.0	14	9.7		54	29.0	37	24.8
Exercise habits (n, %)					0.015					0.153
more than 5 days/week	98	40.2	41	28.3		64	34.4	38	25.5
1–4 days/week	49	20.1	25	17.2		40	21.5	31	20.8
No exercise	97	39.8	79	54.5		82	44.1	80	53.7
Analgesics administration (n, %)					0.183					0.006
No	232	95.1	133	91.7		184	98.9	139	93.3
Yes	12	4.9	12	8.3		2	1.1	10	6.7

Notes: p-values were from the Student’s t-test for continuous variables and the chi-squared test for categorical variables; p-values < 0.05 are in bold; Non-drinker without CP, n = 244; Non-drinker with CP, n = 145; Drinker without CP, n = 186; Drinker with CP, n = 149.

Abbreviations: BMI, body mass index; CRP, C-reactive protein; 25(OH)D, 25-hydroxyvitamin D; CP, chronic pain; SD, standard deviation.

Table 3 Interaction Between CP and Drinking Habits on Serum 25(OH)D Concentrations and Comparison of Adjusted Serum 25(OH)D Values

Drinking Habits	CP Status	Mean	SD	Estimated Mean Difference	95% CI		p1	p2	p3	p4
					Lower	Upper
Non-drinker	Without	22.35	6.77	0.28	−1.09	1.65	0.691	0.021	<0.001	0.098
	With	21.82	6.40
Drinker	Without	27.01	9.24	2.44	0.67	4.22	0.007
	With	25.30	7.83

Notes: Analyses were adjusted for sex, age, body mass index, the smoking status, exercise habit, the analgesics administration status, the osteo sono-assessment index, grip strength/body weight, and calf circumference/body weight; p1, p-value of the one-way analysis of covariance; p2, p-value of main effect of CP on serum 25(OH)D concentrations; p3, p-value of main effect of drinking habits on serum 25(OH)D concentrations; p4, p-value of interaction test between CP and drinking habits on serum 25(OH)D concentrations; p-values < 0.05 are in bold; Bonferroni multiple comparisons post hoc test was performed; Non-drinker without CP, n = 244; Non-drinker with CP, n = 145; Drinker without CP, n = 186; Drinker with CP, n = 149.

Abbreviations: 25(OH)D, 25-hydroxyvitamin D; CP, chronic pain; SD, standard deviation; CI, confidence interval.

Table 4 Logistic Analysis of Chronic Pain as a Dependent Variable with Drinking Habits as an Independent Variable

		OR	95% CI		p-value
			Lower	Upper
All	Model 1	1.427	1.004	2.028	0.048
	Model 2	1.425	0.996	2.038	0.052
	Model 3	1.467	1.018	2.114	0.040

Notes: OR indicates the odds ratio of drinking habits for chronic pain; Model 1, adjusted for sex, age, and BMI; Model 2, adjusted for sex, age, BMI, the smoking status, and exercise habit; Model 3, adjusted for sex, age, BMI, the smoking status, exercise habit, the analgesics administration status, the osteo sono-assessment index, grip strength/body weight, and calf circumference/body weight; p-values < 0.05 are in bold; All, n = 724.

Abbreviations: OR, odds ratio; CI, confidence interval; BMI, body mass index.

Table 5 Logistic Analysis of the Categorized Serum 25(OH)D Levels as a Dependent Variable with Chronic Pain as an Independent Variable

		OR	95% CI		p-value
			Lower	Upper
All	Model 1	0.761	0.541	1.070	0.116
	Model 2	0.777	0.548	1.102	0.157
	Model 3	0.823	0.577	1.174	0.283
Non-drinker	Model 1	0.852	0.549	1.323	0.476
	Model 2	0.896	0.571	1.405	0.631
	Model 3	0.975	0.613	1.552	0.916
Drinker	Model 1	0.534	0.300	0.950	0.033
	Model 2	0.502	0.275	0.915	0.024
	Model 3	0.499	0.268	0.927	0.028

Notes: OR indicates the odds ratio of chronic pain for the categorical 25(OH)D levels; Model 1, adjusted for sex, age, and BMI; Model 2, adjusted for sex, age, BMI, the smoking status, and exercise habit; Model 3, adjusted for sex, age, BMI, the smoking status, exercise habit, the analgesics administration status, the osteo sono-assessment index, grip strength/body weight, and calf circumference/body weight; p-values < 0.05 are in bold; All, n = 724; Non-drinker, n = 389; Drinker, n = 335.

Abbreviations: OR, odds ratio; CI, confidence interval; 25(OH)D, 25-hydroxyvitamin D; BMI, body mass index.