Table 4.
Adjusted Risk Ratios for Hospitalization With an Infection and Hospitalization Without an Infection Among a Cohort of Medicare Beneficiaries (n = 1,512), United States, 2001–2004a,b
| Variable | Hospitalization With Infection vs. No Hospitalization |
P Value | Hospitalization Without Infection vs. No Hospitalization |
P Value | ||
|---|---|---|---|---|---|---|
| RR | 95% CI | RR | 95% CI | |||
| Serum 25(OH)D concentration <15 ng/mL | 2.8 | 1.3, 5.9 | <0.01 | 1.4 | 0.9, 2.1 | 0.1 |
| Female sex | 1.3 | 0.7, 2.6 | 0.4 | 0.8 | 0.6, 1.0 | 0.1 |
| Age, per 1-year increase | 1.0 | 1.0, 1.1 | 0.2 | 1.0 | 1.0, 1.0 | 0.4 |
| Race/ethnicity | ||||||
| Non-Hispanic white | 1.0 | Referent | 1.0 | Referent | ||
| Non-Hispanic black | 0.4 | 0.1, 1.2 | 0.1 | 0.8 | 0.5, 1.1 | 0.1 |
| Mexican-American | 0.6 | 0.3, 1.2 | 0.1 | 0.6 | 0.3, 0.9 | 0.02 |
| Other Hispanic | 0.4 | 0.0, 4.2 | 0.5 | 1.1 | 0.6, 2.0 | 0.8 |
| Other | 0.6 | 0.1, 2.7 | 0.5 | 0.7 | 0.2, 2.3 | 0.6 |
| Poverty-index ratio <2.0 | 1.2 | 0.7, 2.3 | 0.5 | 1.4 | 0.9, 2.1 | 0.1 |
| Body mass indexc category | ||||||
| <25 | 1.0 | Referent | 1.0 | Referent | ||
| 25–29 | 0.7 | 0.3, 1.6 | 0.5 | 0.9 | 0.6, 1.4 | 0.6 |
| ≥30 | 0.8 | 0.4, 1.7 | 0.6 | 1.2 | 0.8, 1.9 | 0.4 |
| Latitude | ||||||
| <32°N | 1.0 | Referent | 1.0 | Referent | ||
| 32°N–38°N | 0.7 | 0.4, 1.3 | 0.2 | 0.5 | 0.3, 0.8 | <0.01 |
| ≥39°N | 0.7 | 0.4, 1.4 | 0.3 | 0.6 | 0.4, 0.9 | 0.02 |
| Cancerd | 1.2 | 0.6, 2.3 | 0.6 | 1.3 | 1.0, 1.7 | 0.1 |
| Renal disease | 3.5 | 1.5, 8.2 | <0.01 | 1.9 | 1.1, 3.4 | 0.02 |
| Diabetes mellitus | 1.4 | 0.6, 3.5 | 0.4 | 2.0 | 1.4, 2.7 | <0.01 |
Abbreviations: CI, confidence interval; 25(OH)D, 25-hydroxyvitamin D; RR, risk ratio.
a Data from the 2001–2002 and 2003–2004 cycles of the National Health and Nutrition Examination Survey.
b Global test of the null hypothesis—likelihood ratio test: P < 0.01; Wald test: P < 0.01.
c Body mass index was calculated as weight (kg)/height (m)2.
d Excluding nonmelanoma skin cancers.