Table 2.
Standardized differences in cumulative all-cause mortality at 2, 5, and 10 years of follow-up by level of social engagement at baseline among residents in nursing homes in Madrid, Spain
| Level of social engagement at baseline | |||
|---|---|---|---|
| Low/null | Moderate | High | |
| No. of person-years | 691.1 | 1042.2 | 571.6 |
| No. of deaths | 92 | 133 | 43 |
| Mortality ratea | 11.6 | 12.8 | 6.6 |
| 2-year follow-up | |||
| Cumulative mortalityb (%) | 11.8 | 18.8 | 8.1 |
| Standardized risk differencec (95% CI) | |||
| Model 1d | 0.0 (reference) | 3.9 (−4.4 to 12.1) | −6.5 (−15.0 to 1.9) |
| Model 2e | 0.0 (reference) | 5.0 (−3.5 to 13.4) | −2.3 (−13.9 to 9.3) |
| Model 3f | 0.0 (reference) | 6.5 (−2.3 to 15.4) | −0.6 (−11.8 to 10.7) |
| 5-year follow-up | |||
| Cumulative mortalityb (%) | 47.4 | 46.2 | 20.1 |
| Standardized risk differencec (95% CI) | |||
| Model 1d | 0.0 (reference) | −3.7 (−15.6 to 8.2) | −24.3 (− 37.4 to −11.1) |
| Model 2e | 0.0 (reference) | −4.5 (−16.7 to 7.8) | −22.5 (−38.2 to −6.7) |
| Model 3f | 0.0 (reference) | −2.3 (−14.6 to 10.0) | −18.4 (−33.8 to −2.9) |
| 10-year follow-up | |||
| Cumulative mortalityb (%) | 68.9 | 74.4 | 50.5 |
| Standardized risk differencec (95% CI) | |||
| Model 1d | 0.0 (reference) | 4.3 (−7.3 to 15.9) | −9.4 (−25.8 to 7.1) |
| Model 2e | 0.0 (reference) | 3.8 (−7.7 to 15.3) | −9.3 (−26.0 to 7.4) |
| Model 3f | 0.0 (reference) | 4.6 (−7.4 to 16.6) | −7.5 (−24.2 to 9.3) |
a Sampling-weighted mortality rates per 100 person-years
bUnstandardized cumulative mortality risks at the specified follow-up times were obtained from sampling-weighted Kaplan-Meier methods stratified by level of social engagement at baseline
c Standardized differences in cumulative mortality at the specified follow-up times which compared levels of social engagement at baseline were obtained from spline-based survival models weighted by combined inverse probability weights and stratified by level of social engagement. 95% confidence intervals (CIs) were derived from robust standard errors of spline coefficients by applying delta methods
d Model 1 was standardized for baseline age (65–74, 75–79, 80–84, 85–89, or ≥ 90 years), sex (women or men), educational level (less than primary, primary, or secondary or more), and marital status (married, single, or widowed/divorced)
e Model 2 was further standardized for baseline facility ownership (public/subsidized or private), facility size (< 100, 100–299, or ≥ 300 beds), length of stay (0–1, 2–4, or ≥ 5 years), assigned caregiver (yes or no), and frequency of external visits (monthly or less, weekly, or daily)
f Model 3 was further standardized for baseline number of chronic conditions (0–1, 2–3, or ≥ 4) and functional dependency (no, mild, or moderate)