Multivariate analysis for PV, IPSS and the IIEF-5 score
| PV | IPSS | IIEF-5 score | ||||
|---|---|---|---|---|---|---|
| Variables | β (95% CI) | p Value | β (95% CI) | p Value | β (95% CI) | p Value |
| Model 1 (included age, BMI, education, smoking, alcohol consumption and diet (weekly)) | ||||||
| Age (years) | 0.44 (0.35 to 0.53) | <0.001 | 0.13 (0.10 to 0.16) | <0.001 | −0.03 (−0.04 to −0.02) | <0.001 |
| BMI (kg/m2) | 0.42 (0.19 to 0.65) | <0.001 | 0.08 (0.01 to 0.16) | 0.030 | −0.02 (−0.04 to −0.01) | <0.001 |
| Education (≤9/>9 years) | −1.60 (−3.40 to 0.20) | 0.081 | −1.50 (−2.08 to −0.91) | <0.001 | 0.10 (0.01 to 0.18) | 0.025 |
| Smoking (no/yes) | 1.14 (−0.50 to 2.78) | 0.173 | 0.89 (0.36 to 1.42) | 0.001 | −0.01 (−0.08 to 0.08) | 0.979 |
| Alcohol consumption (no/yes) | 0.72 (−0.96 to 2.39) | 0.400 | 0.32 (−0.22 to 0.86) | 0.246 | 0.01 (−0.07 to 0.09) | 0.794 |
| Meat, fish and eggs (times/week) | 0.05 (−0.21 to 0.31) | 0.711 | −0.11 (−0.18 to −0.01) | 0.031 | 0.01 (−0.01 to 0.02) | 0.095 |
| Vegetables (times/week) | 0.80 (0.46 to 1.14) | <0.001 | 0.09 (−0.02 to 0.20) | 0.127 | −0.04 (−0.05 to −0.02) | <0.001 |
| Milk and dairy products (times/week) | −0.07 (−0.19 to 0.05) | 0.272 | 0.06 (0.02 to 0.10) | 0.005 | −0.08 (−0.13 to −0.04) | 0.001 |
| Model 2 (adjusted for age, BMI, education, smoking, alcohol consumption) | ||||||
| Northern China | ref | – | ref | – | ref | – |
| Southern China | 7.52 (5.48 to 9.57) | <0.001 | −1.42 (−2.08 to −0.76) | <0.001 | −0.05 (−0.14 to 0.05) | 0.369 |
| Northwestern China | −2.94 (−5.10 to −0.78) | 0.008 | 2.49 (1.79 to 3.18) | <0.001 | −0.21 (−0.31 to −0.10) | <0.001 |
Log change was performed for non-normally distributed data (IIEF-5); multiple linear regression was performed.
β: Unstandardised coefficients.
BMI, body mass index; IIEF-5, International Index of Erectile Function 5; IPSS, International Prostate Symptom Score; PV, prostate volume.