TABLE 2.
Cox proportional hazards results for the relation between sedentary, light, and moderate-to-vigorous time and mortality in the overall study sample, and in low- and high-active groups1
| Models | Sedentary | Light | Moderate-to-vigorous |
| Overall (n = 4840, 700 deaths) | |||
| Single-factor models2 | 1.13 (1.09, 1.18) | 0.50 (0.38, 0.65) | 0.73 (0.65, 0.82) |
| 2-factor model3 | 1.05 (1.00, 1.10) | 0.53 (0.40, 0.71) | — |
| 2-factor model3 | — | 0.83 (0.74, 0.93) | 0.59 (0.44, 0.77) |
| Partition model4 | 1.03 (0.98, 1.08) | 0.84 (0.75, 0.95) | 0.60 (0.45, 0.81) |
| Low active (<5.8 h/d, n = 2618, 576 deaths)4 | |||
| Single-factor models2 | 1.14 (1.08, 1.20) | 0.71 (0.61, 0.83) | 0.31 (0.21, 0.46) |
| 2-factor model3 | 1.07 (1.02, 1.13) | — | 0.41 (0.28, 0.59) |
| 2-factor model3 | — | 0.82 (0.72, 0.94) | 0.37 (0.26, 0.53) |
| Partition model4 | 1.06 (1.00, 1.11) | 0.84 (0.74, 0.96) | 0.39 (0.27, 0.56) |
| High active (≥5.8 h/d, n = 2222, 124 deaths)4 | |||
| Single-factor models2 | 0.92 (0.82, 1.04) | 0.87 (0.56, 1.34) | 1.21 (0.88, 1.66) |
| 2-factor model3 | 0.89 (0.79, 1.00) | 0.80 (0.52, 1.24) | — |
| 2-factor model3 | — | 1.19 (0.85, 1.68) | 0.89 (0.58, 1.39) |
| Partition model4 | 0.90 (0.79, 1.03) | 0.83 (0.52, 1.32) | 1.16 (0.80, 1.66) |
Values are HRs (95% CIs) and adjusted for age, race, education, sex, smoking status, alcohol use, BMI, mobility limitation, and a history of the following conditions: diabetes, coronary artery disease, stroke, and cancer. Activity intensities are defined as sedentary time (AC <100) and light- (100 ≥ AC < 760) and moderate-to-vigorous–intensity physical activity (AC ≥760). Low- and high-active designations were based on sample-weighted medians of total active time (AC >100 min/d). There were statistically significant (P < 0.01) interactions between total activity level and sedentary time on mortality, and for total activity and both intensities of physical activity. AC, activity count.
Single-factor models are results from separate models for each type of behavior, adjusted only for covariates.
Two-factor model results are from separate models that included either sedentary time and light activity or sedentary time and moderate-to-vigorous activity and covariates, and “—“ indicates the variable was not included in the model.
Partition model results are from a single model that included sedentary time, light and moderate-to-vigorous activity, and covariates.