| 2 (vs. 1) ED visits | ≥ 3 (vs. 1) ED visits | ||
---|---|---|---|---|
Variables | Odds ratio (95% CI) | P value | Odds ratio (95% CI) | P value |
Age, y | Â | <0.001 | Â | <0.001 |
 40-54 years | 1 [reference] |  | 1 [reference] |  |
 55-64 years | 1.15 (1.09-1.22) | <0.001 | 1.31 (1.23-1.39) | <0.001 |
 65-74 years | 1.14 (1.07-1.22) | <0.001 | 1.11 (1.03-1.20) | 0.006 |
 75-84 years | 1.05 (0.98-1.12) | 0.10 | 0.86 (0.79-0.93) | <0.001 |
 85 years and older | 0.90 (0.83-0.97) | 0.03 | 0.58 (0.52-0.64) | <0.001 |
Male sex | 1.04 (1.00-1.08) | 0.048 | 1.12 (1.07-1.17) | <0.001 |
Race/ethnicity | Â | Â | Â | Â |
 Non-hispanic white | 1.15 (1.08-1.21) | <0.001 | 1.32 (1.23-1.41) | <0.001 |
 Non-hispanic black | 1.17 (1.09-1.27) | <0.001 | 1.59 (1.46-1.73) | <0.001 |
 Hispanic | 1 [reference] |  | 1 [reference] |  |
 Other | 1.07 (0.96-1.19) | 0.29 | 1.07 (0.96-1.19) | 0.33 |
Insurance status | Â | Â | Â | Â |
 Medicare | 1.58 (1.47-1.69) | <0.001 | 2.10 (1.92-2.29) | <0.001 |
 Medicaid | 1.77 (1.64-1.92) | <0.001 | 2.92 (2.66-3.20) | <0.001 |
 Private | 1 [reference] |  | 1 [reference] |  |
 Self-pay | 1.11 (1.00-1.23) | 0.046 | 1.05 (0.92-1.20) | 0.45 |
 Other | 1.46 (1.32-1.62) | <0.001 | 1.78 (1.57-2.02) | <0.001 |
Quartiles for median household income of patient’s ZIP code |  |  | ||
 1 (lowest) | 1.13 (1.07-1.20) | <0.001 | 1.29 (1.21-1.38) | <0.001 |
 2 | 1.11 (1.05-1.18) | <0.001 | 1.22 (1.14-1.31) | <0.001 |
 3 | 1.08 (1.01-1.14) | 0.01 | 1.14 (1.06-1.22) | <0.001 |
 4 (highest) | 1 [reference] |  | 1 [reference] |  |
Patient residence | Â | Â | Â | Â |
 Counties of ≥ 1 million population | 1.07 (1.00-1.15) | 0.06 | 1.09 (1.01-1.18) | 0.03 |
 Counties of 250,000-999,999 population | 1.07 (1.00-1.15) | 0.07 | 1.09 (1.00-1.18) | 0.06 |
 Counties of 50,000-249,999 population | 1.09 (1.00-1.20) | 0.06 | 1.10 (0.99-1.23) | 0.09 |
 Counties of < 50,000 population | 1 [reference] |  | 1 [reference] |  |
State | Â | Â | Â | Â |
 California | 1.01 (0.98-1.05) | 0.44 | 1.06 (1.02-1.11) | 0.006 |
 Florida | 1 [reference] |  | 1 [reference] |  |
Selected comorbidities* | Â | Â | Â | Â |
 Congestive heart failure | 1.17 (1.11-1.22) | <0.001 | 1.24 (1.17-1.30) | <0.001 |
 Pulmonary circulation disorders | 1.41 (1.22-1.64) | <0.001 | 1.39 (1.17-1.64) | <0.001 |
 Diabetes, uncomplicated | 1.05 (1.01-1.10) | 0.02 | 1.13 (1.07-1.19) | <0.001 |
 Obesity | 0.99 (0.94-1.05) | 0.79 | 0.97 (0.91-1.03) | 0.31 |
 Depression | 1.21 (1.14-1.28) | <0.001 | 1.38 (1.30-1.47) | <0.001 |
 Psychoses | 1.17 (1.09-1.27) | <0.001 | 1.27 (1.17-1.38) | <0.001 |
 Drug abuse | 1.22 (1.09-1.37) | <0.001 | 1.66 (1.48-1.85) | <0.001 |