Table 2.
Frailty and Risk for All-Cause and Cause-Specific Hospitalizationa
| All-cause | Chronic | Infectious | Nonchronic, Noninfectious | |
|---|---|---|---|---|
| HR (95% CI) | HR (95% CI) | HR (95% CI) | HR (95% CI) | |
| Time-updated frailty modelsb | ||||
| Age (per 5 y) | 1.03 (0.96, 1.10) | 1.08 (0.99, 1.18) | 0.99 (0.89, 1.09) | 1.08 (0.98, 1.18) |
| Female | 1.41 (1.17, 1.70) | 1.43 (1.11, 1.84) | 1.41 (1.06, 1.88) | 1.25 (0.96, 1.61) |
| African American | 0.88 (0.64, 1.21) | 0.93 (0.59, 1.47) | 0.93 (0.56, 1.56) | 0.94 (0.59, 1.50) |
| Less than high school education | 0.94 (0.79, 1.13) | 0.95 (0.74, 1.21) | 1.07 (0.80, 1.42) | 0.93 (0.73, 1.19) |
| Unemployed | 1.92 (1.49, 2.48) | 2.37 (1.62, 3.48) | 1.85 (1.19, 2.87) | 1.65 (1.18, 2.32) |
| Homeless | 1.42 (1.10, 1.84) | 1.59 (1.12, 2.25) | 1.48 (1.02, 2.14) | — |
| Hazardous alcohol use | 1.30 (1.06, 1.60) | 1.37 (1.05, 1.80) | — | 1.46 (1.11, 1.92) |
| Recent injection drug use | 1.25 (1.03,1.51) | — | 2.32 (1.73, 3.11) | — |
| Prescription drug abuse | 1.40 (1.05, 1.87) | — | 1.66 (1.11, 2.48) | — |
| Number of comorbid conditionsd | ||||
| 0 | Ref | Ref | Ref | |
| 1 | 1.26 (1.01, 1.56) | 1.37 (1.00, 1.88) | — | 1.43 (1.05, 1.97) |
| 2 | 1.32 (1.01, 1.71) | 1.61 (1.13, 2.30) | — | 1.69 (1.18, 2.43) |
| ≥3 | 2.37 (1.80, 3.14) | 2.71 (1.88, 3.91) | — | 3.01 (2.09, 4.36) |
| HIV status | ||||
| Negative | Ref | Ref | Ref | Ref |
| HIV+, no AIDS | 1.27 (1.03, 1.56) | 0.89 (0.67, 1.20) | 2.64 (1.93, 3.61) | 1.10 (0.82, 1.47) |
| HIV+, AIDS | 2.74 (2.05, 3.67) | 1.55 (1.02, 2.34) | 7.69 (5.30, 11.2) | 2.10 (1.43, 3.09) |
| Frailty status—time updatede | ||||
| Robust | Ref* | Ref* | Ref* | Ref† |
| Prefrail | 1.12 (0.91, 1.39) | 1.19 (0.88, 1.61) | 1.12 (0.79, 1.57) | 1.14 (0.85, 1.52) |
| Frail | 1.53 (1.16, 2.03) | 2.27 (1.58, 3.27) | 1.70 (1.11, 2.60) | 1.50 (1.03, 2.18) |
| Baseline frailty modelsc | ||||
| Frailty status—baselinee | ||||
| Robust | Ref* | Ref* | Ref* | Ref‡ |
| Prefrail | 1.00 (0.81, 1.23) | 1.21 (0.90, 1.64) | 1.32 (0.92, 1.90) | 0.93 (0.70, 1.23) |
| Frail | 1.41 (1.06, 1.87) | 2.13 (1.46, 3.11) | 2.51 (1.60, 3.91) | 1.09 (0.74, 1.61) |
Note: CI = confidence interval; HR = hazard ratio; y = years
aData are adjusted HR (95% CIs).
bMultivariable models evaluating the relationship of frailty as a time-varying covariate with hospitalization.
cMultivariable models examining the relationship of the index (baseline) frailty measure with hospitalization, adjusting for the covariates listed in each respective time-updated model.
dDiabetes, hypertension, cerebrovascular accident, cardiovascular disease, renal disease, chronic obstructive pulmonary disease, cancer, obesity, and liver disease.
eRobust participants had a frailty score of 0; prefrail participants had a frailty score of 1–2; and frail participants had a frailty score of 3–5.
Level of significance for each boldface value: p < .05.
Global p: *p < .05; †p = .11; ‡p = .69.