Table 5.
Association between hospital exposures and mobility outcomes according to study group
| Physical activity (N = 818) | Health education (N = 817) | ||||||
|---|---|---|---|---|---|---|---|
| Outcome rate per 100 person-year | Outcome rate per 100 person-year | ||||||
| Exposurea | Hospitalized | Not hospitalized | HR (95% CI) | Hospitalized | Not hospitalized | HR (95% CI) | P value* |
| Onset of MMD | |||||||
| Any hospitalization | 39 (31–48) | 10 (8–13) | 3.3 (2.5–4.3) | 46 (37–59) | 14 (11–16) | 3.2 (2.5–4.1) | 0.903 |
| Number of hospitalizations | |||||||
| 0 (ref) | 10 (8–13) | 1.0 | 14 (11–16) | 1.0 | 0.742 | ||
| 1 | 36 (28–46) | 3.0 (2.2–4.0) | 39 (30–51) | 2.7 (2.0–3.6) | |||
| 2 or more | 50 (34–73) | 4.3 (2.8–6.8) | 79 (57–109) | 5.1 (3.4–7.6) | |||
| Number of days hospitalizedb | |||||||
| 0 (ref) | 13 (11–15) | 1.0 | 16 (13–19) | 1.0 | 0.804 | ||
| 3 | 15 (13–18) | 1.2 (1.2–1.3) | 19 (16–23) | 1.2 (1.2–1.3) | |||
| 10 | 23 (19–28) | 1.9 (1.6–2.1) | 29 (24–36) | 1.9 (1.6–2.2) | |||
| Any hospitalizationc | Recovery from MMD d | ||||||
| Model 1 | 43 (27–69) | 64 (46–89) | 0.60 (0.35–1.04) | 33 (21–53) | 51 (37–70) | 0.51 (0.28–0.90) | 0.670 |
| Model 2 | 52 (33–80) | 71 (50–99) | 0.59 (0.39–0.88) | 34 (21–54) | 56 (40–77) | 0.45 (0.27–0.74) | 0.392 |
| Model 3 | 43 (27–68) | 64 (46–89) | 0.60 (0.35–1.03) | 33 (21–53) | 51 (37–69) | 0.51 (0.29–0.92) | 0.688 |
Abbreviations: CI confidence interval, HR hazard ratio, MMD major mobility disability, ref reference group
* Values represent statistical interaction between exposure and study group on mobility outcome
aAssessed during the interval preceding the outcome
b Values for outcome rates are provided for a range of fixed values assuming a log-linear relationship. Three days was the median length of hospital stay, and 10 days allowed for long lengths of stay and more than one hospital admission
c Results are not available for the number of hospitalizations or number of days hospitalized because the number of participants with more than one hospitalization during the at-risk period was small
d All models include clinical site, age, and gender as covariates; Model 2 uses inverse probability weighting based on MMD, whereas Model 3 uses inverse probability weighting based on withdrawal/missed follow-up, as described in the Methods