Social engagement within the facility increased life expectancy in nursing home residents: a follow-up study

BMC Geriatrics

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 rate^a	11.6	12.8	6.6
2-year follow-up
Cumulative mortality^b (%)	11.8	18.8	8.1
Standardized risk difference^c (95% CI)
Model 1^d	0.0 (reference)	3.9 (−4.4 to 12.1)	−6.5 (−15.0 to 1.9)
Model 2^e	0.0 (reference)	5.0 (−3.5 to 13.4)	−2.3 (−13.9 to 9.3)
Model 3^f	0.0 (reference)	6.5 (−2.3 to 15.4)	−0.6 (−11.8 to 10.7)
5-year follow-up
Cumulative mortality^b (%)	47.4	46.2	20.1
Standardized risk difference^c (95% CI)
Model 1^d	0.0 (reference)	−3.7 (−15.6 to 8.2)	−24.3 (− 37.4 to −11.1)
Model 2^e	0.0 (reference)	−4.5 (−16.7 to 7.8)	−22.5 (−38.2 to −6.7)
Model 3^f	0.0 (reference)	−2.3 (−14.6 to 10.0)	−18.4 (−33.8 to −2.9)
10-year follow-up
Cumulative mortality^b (%)	68.9	74.4	50.5
Standardized risk difference^c (95% CI)
Model 1^d	0.0 (reference)	4.3 (−7.3 to 15.9)	−9.4 (−25.8 to 7.1)
Model 2^e	0.0 (reference)	3.8 (−7.7 to 15.3)	−9.3 (−26.0 to 7.4)
Model 3^f	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)

ISSN: 1471-2318