The Relationship Between Serum 25-Hydroxyvitamin D Levels and Osteoporosis in Postmenopausal Women

Figures & data

Figure 1 Flow chart of research sample selection.

Table 1 Weighted Characteristics of the Study Participants Based on Serum 25-Hydroxyvitamin D [25(OH)D] Concentrations

Characteristics	Serum 25(OH)D Concentrations (nmol/L)			P value
	<50 (n = 574)^a	50–<75 (n = 683)^b	≥75 (n = 801)^c
Age (years), mean (SE)	61.61 (0.42)	61.40 (0.43)	62.06 (0.33)	0.387
Race, n (%)				<0.001
Non-Hispanic white	181 (59.59)	289 (71.27)	465 (83.17)
Non-Hispanic black	195 (22.15)	107 (8.03)	114 (5.79)
Mexican American	122 (8.37)	143 (7.01)	64 (2.41)
Other race	76 (9.90)	144 (13.69)	158 (8.64)
Education level, n (%)				0.002
Less than high school	180 (21.53)	195 (18.12)	142 (11.38)
High school	152 (30.88)	164 (27.05)	209 (28.69)
More than high school	242 (47.59)	324 (54.83)	450 (59.93)
Family PIR, mean (SE)	2.83 (0.11)	3.07 (0.07)	3.46 (0.08)	<0.001
Body mass index (kg/m^2), mean (SE)	30.33 (0.28)	27.85 (0.24)	27.14 (0.34)	<0.001
Total calcium (mmol/L), mean (SE)	2.36 (0.00)	2.37 (0.00)	2.38 (0.00)	0.051
Serum phosphorus (mmol/L), mean (SE)	1.25 (0.01)	1.26 (0.01)	1.27 (0.01)	0.193
Smoking behavior, n (%)				<0.001
Never	312 (50.98)	444 (62.32)	505 (60.78)
Current	131 (23.48)	94 (14.84)	81 (11.10)
Former	131 (25.53)	145 (22.84)	215 (28.12)
Alcohol consumption, n (%)				0.001
Non-drinker	288 (43.50)	319 (34.36)	312 (31.03)
Moderate drinker	134 (27.62)	219 (39.94)	308 (41.26)
Heavy drinker	152 (28.87)	145 (25.69)	181 (27.70)
Moderate activities, n (%)				<0.001
Yes	262 (48.94)	398 (64.76)	494 (68.58)
No	312 (51.06)	285 (35.24)	307 (31.42)
Survey months, n (%)				0.005
November to April (Winter months)	303 (47.62)	321 (36.16)	320 (34.32)
May to October (Summer months)	271 (52.38)	362 (63.84)	481 (65.68)
Years since menopause (years), mean (SE)	15.20 (0.47)	14.61 (0.54)	15.75 (0.48)	0.346

Notes: Except for sample sizes, all estimates are weighted. Values are weighted mean (SE) or n (weighted %). ^aWeighted n = 3,403,621. ^bWeighted n = 5,281,840. ^cWeighted n = 7,509,745.

Abbreviations: SE, standard error; PIR, poverty income ratio.

Table 2 Associations Between Serum 25(OH)D and Osteoporosis of Total Femur, Femoral Neck and Lumbar Spine

25(OH)D (nmol/L)	Model 1^a	Model 2^b	Model 3^c
	OR (95% CI) P value	OR (95% CI) P value	OR (95% CI) P value
Total femur
<50	Reference	Reference	Reference
50 to <75	0.389 (0.229, 0.663) <0.001	0.232 (0.126, 0.427) <0.001	0.274 (0.138, 0.544) <0.001
≥75	0.494 (0.296, 0.825) 0.009	0.274 (0.154, 0.489) <0.001	0.374 (0.202, 0.693) 0.003
Femoral neck
<50	Reference	Reference	Reference
50 to <75	0.678 (0.452, 1.017) 0.064	0.430 (0.275, 0.672) <0.001	0.537 (0.328, 0.879) 0.016
≥75	0.731 (0.474, 1.126) 0.159	0.413 (0.239, 0.714) 0.002	0.583 (0.331, 1.026) 0.066
Lumbar spine
<50	Reference	Reference	Reference
50 to <75	0.815 (0.515, 1.289) 0.384	0.573 (0.344, 0.954) 0.036	0.614 (0.357, 1.055) 0.083
≥75	0.812 (0.525, 1.258) 0.355	0.533 (0.336, 0.846) 0.009	0.627 (0.368, 1.067) 0.091

Notes: Bold fonts indicate statistically significant. ^aNo covariates were adjusted. ^bAge, race, and BMI were adjusted. ^cAge, race, education level, family PIR, BMI, total calcium, serum phosphorus, smoking behavior, alcohol consumption, moderate activities, survey months, and years since menopause were adjusted.

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

Figure 2 Forest plot of age-stratified analyses of the associations between serum 25(OH)D and osteoporosis. (Age, race, education level, family PIR, BMI, total calcium, serum phosphorus, smoking behavior, alcohol consumption, moderate activities, survey months, and years since menopause were adjusted).

Figure 3 Forest plot of BMI stratified analyses of the associations between serum 25(OH)D and osteoporosis. (Age, race, education level, family PIR, BMI, total calcium, serum phosphorus, smoking behavior, alcohol consumption, moderate activities, survey months, and years since menopause were adjusted).

Figure 4 Forest plot of survey months stratified analyses of the associations between serum 25(OH)D and osteoporosis. (Age, race, education level, family PIR, BMI, total calcium, serum phosphorus, smoking behavior, alcohol consumption, moderate activities, and years since menopause were adjusted).