Table 2.
Cox Proportional Hazards Regression Models Analyses of the Relationship Between Disability and IGF-1 Levels
| IGF-1 Level | Model 1 | Model 2 | Model 3 | |||
|---|---|---|---|---|---|---|
| HR (95% CI) | p | HR (95% CI) | p | HR (95% CI) | p | |
| Q1 (lowest) | 4.40 (2.77–7.00) | <.001 | 1.91 (1.18–3.10) | .009 | 1.72 (1.06–2.81) | .028 |
| Q2 | 2.44 (1.49–4.01) | <.001 | 1.73 (1.05–2.86) | .032 | 1.64 (0.99–2.71) | .054 |
| Q3 | 1.59 (0.93–2.72) | .091 | 1.42 (0.83–2.43) | .200 | 1.31 (0.76–2.25) | .328 |
| Q4 (highest) | Reference | Reference | Reference | |||
Notes: BMI = body mass index; CI: confidence intervals; GDS = Geriatric Depression Scale; HR: hazard ratio; IGF-1 = insulin-like growth factor-1; MMSE = Mini Mental State Examination. Model 1: crude model; Model 2: adjusted for age, sex, BMI, number of chronic diseases (hypertension, hyperlipidemia, and diabetes), number of medications used, years of education, sleep duration, habit of alcohol drinking and smoking, habit of physical exercise, and GDS; Model 3: MMSE score and gait speed added to Model 2.