Table 3.
Demographic Model, Candidate Variable Model and Final Model Logistic Regression Examining Associations between Selected Variables and osteoporosis (T-score < −1.8)1 adjusted for Selected Characteristics among 337 Postmenopausal Caucasian Women
| Demographic Model2 | Candidate Variable Model3 | Final Model 4 | ||||
|---|---|---|---|---|---|---|
| OR | 95%CI | OR | 95%CI | |||
| Age (Continuous) | 1.08* | (1.05–1.11) | 1.08* | (1.06–1.12) | ||
| BMI (Continuous) | 0.93* | (0.88–0.98) | 0.91* | (0.86–0.97) | ||
| Education Level: | ||||||
| No Bachelor’s degree | 1.0 | Referent | 1.0 | Referent | ||
| Bachelor’s degree | 1.02 | (0.53–1.99) | 1.06 | (0.53–2.14) | ||
| Graduate degree | 0.78 | (0.38–1.63) | 0.84 | (0.38–1.86) | ||
| Soy milk intake: | ||||||
| Never (0/month) | 1.0 | Referent | 1.0 | Referent | ||
| Once a month or more (1–29 per month) | 1.29 | (0.69–2.42) | 0.90 | (0.44–1.82) | ||
| Once a day or more (30+ per month) | 0.64 | (0.34–1.22) | 0.43* | (0.21–0.89) | ||
| Trend | P =0.04 | |||||
| Dairy Consumption: | ||||||
| Less than twice a week (0–7/month) | 1.0 | Referent | 1.0 | Referent | ||
| Twice a week or more (8–29/month) | 0.65 | (0.35–1.20) | 0.55 | (0.28–1.11) | ||
| Once a day or more (30+/month) | 0.48* | (0.25–0.92) | 0.38* | (0.17–0.86) | ||
| Trend | P =0.02 | |||||
| Estrogen Usage: | ||||||
| Past/never Users | 1.0 | Referent | 1.0 | Referent | ||
| Current Users | 0.25 | (0.12–0.52) | 0.27 | (0.13–0.56) | ||
| Smoking Status: | ||||||
| Never smokers | 1.0 | Referent | ||||
| Ever smokers | 1.53 | (0.58–4.04) | ||||
| Self-reported Health Status: | ||||||
| Excellent/Good | 1.0 | Referent | ||||
| Fair/Poor | 2.40* | (1.11–5.17) | ||||
| History of Minor Accident Fractures: | ||||||
| No | 1.0 | Referent | ||||
| Yes | 1.59 | (0.87–2.89) | ||||
| Physical Activity Level: | ||||||
| Level 1 (None) | 1.0 | Referent | ||||
| Level 2 (1–104 min/wk of Walk/Run/Jog) | 0.82 | (0.37–1.82) | ||||
| Level 3 (105–174 min/wk of Walk/Run/Jog) | 0.69 | (0.33–1.45) | ||||
| Level 4 (≥ 175 min/wk of Walk/Run/Jog) | 0.99 | (0.46–2.11) | ||||
| Vegetarian Status: | ||||||
| Meat Consumers | 1.0 | Referent | 1.0 | Referent | ||
| Vegetarians (meat intake < 1x/month) | 0.79 | (0.45–1.39) | 0.65 | (0.34–1.23) | ||
| Soyfood (Tofu, Soy cheese) intake: | ||||||
| Never (0/month) | 1.0 | Referent | ||||
| Less than twice a week (1–7 per month) | 1.26 | (0.64–2.47) | ||||
| Twice a week or more (8+ per month) | 1.17 | (0.59–2.30) | ||||
| Calcium Supplement: | ||||||
| Never Users | 1.0 | Referent | ||||
| Use for less than 5 years | 1.24 | (0.66–2.30) | ||||
| Use for 5 years or more | 0.91 | (0.49–1.70) | ||||
| Vitamin D Supplement: | ||||||
| Never Users | 1.0 | Referent | ||||
| Use for less than 5 years | 2.03 | (0.90–4.59) | ||||
| Use for 5 years or more | 1.66 | (0.62–4.45) | ||||
1
T-score ≥ −1.8 (value=0, n=237); T-score < −1.8 (value=1, n=100)
2
Demographic Model: Osteoporotic T-score = age + BMI + Education
3
Candidate Variable Model: Osteoporotic T-score = age + BMI + Education + one exposure variable
4
Final Model (included only the variables that changed the effect of dairy or soy milk by at least 10%):
Osteoporotic T-score = age + BMI + education + estrogen use + dairy consumption + vegetarian status + soy milk intake
*
P < 0.05