Table 2.
Risk Factors for Adverse Drug Events Treated in U.S. Outpatient Clinics and Emergency Departments, 1995–2005
| Risk Factors | Odds Ratio | 95% CI |
|---|---|---|
| Year of ADE Visit | 1.00 | 0.98–1.02 |
| Age group, y | ||
| 0–4 | Referent | |
| 5–17 | 0.92 | 0.69–1.24 |
| 18–44 | 1.46 | 1.17–1.82 |
| 45–64 | 1.83 | 1.45–2.31 |
| ≥ 65 | 2.13 | 1.63–2.79 |
| Gender | ||
| Female | 1.51 | 1.33–1.70 |
| Male | Referent | |
| Race/ethnicitya | ||
| Non-Hispanic White | 0.94 | 0.74–1.19 |
| Non-Hispanic Black | 0.69 | 0.53–0.90 |
| Hispanic | 0.87 | 0.65–1.17 |
| Other | Referent | |
| Number of Medications b | ||
| 1 to 2 | Referent | |
| 3 to 4 | 1.44 | 1.24–1.67 |
| 5 or more | 1.88 | 1.56–2.24 |
| Payment sourcea | ||
| Private insurance | 1.11 | 0.83–1.50 |
| Government | 1.00 | 0.72–1.38 |
| Self-pay | 0.77 | 0.55–1.09 |
| Other | Referent | |
| Region | ||
| Northeast | 0.88 | 0.72–1.06 |
| Midwest | 0.83 | 0.70–1.00 |
| South | 0.87 | 0.73–1.04 |
| West | Referent |
Abbreviations: CI, confidence interval; ADE adverse drug event
a
Among outpatient clinic cases there were 198 cases with missing race/ethnicity data and 103 cases with missing payment data. Among emergency department cases, 230 and 142 cases were missing race/ethnicity and payment data, respectively.
b
Refers to the number of medications a patient was taking at the time of the ADE visit.