Table 2.
Site-Level Characteristics by Quartiles of Percent Change in 30-Day Risk-Adjusted Readmission Rates, 2009–2012
| Variable | Overall (N = 70) |
Best Quartile (n = 17)* |
Quartile 2 (n = 18)* |
Quartile 3 (n = 18)* |
Worst Quartile (n = 17)* |
P Value |
|---|---|---|---|---|---|---|
| Mean age, median (quartiles), y | 80.0 (78.2–81.7) | 80.7 (78.2–81.7) | 80.7 (78.2–82.2) | 79.9 (78.2–80.8) | 79.4 (78.7–81.3) | .81 |
| Female, median (quartiles), % | 53.6 (50.2–57.8) | 56.3 (51.2–59.2) | 52.6 (49.6–57.4) | 52.7 (47.1–55.9) | 54.3 (51.4–58.2) | .36 |
| Race other than white, median (quartiles), % | 14.6 (6.5–31.3) | 15.4 (5.1–30.3) | 18.0 (10.8–35.7) | 10.7 (4.2–30.2) | 12.2 (7.3–39.2) | .65 |
| Insurance, median (quartiles), % | ||||||
| Medicare | 83.1 (43.3–97.2) | 77.8 (39.3–91.5) | 83.9(53.0–96.7) | 93.2 (50.9–98.0) | 67.9 (38.3–97.2) | .44 |
| Medicaid | 3.0 (0.3–8.3) | 5.3 (1.5–7.7) | 3.2 (0.4–14.8) | 1.1 (0.0–6.7) | 3.1 (0.4–8.1) | .54 |
| Other | 13.0 (1.8–36.5) | 11.11 (4.5–36.5) | 13.0 (1.9–27.5) | 5.3 (1.1–35.6) | 21.1 (2.2–38.7) | .63 |
| Medical history, median (quartiles), % | ||||||
| Atrial fibrillation | 40.0 (32.6–44.9) | 40.0 (34.0–42.9) | 34.9 (32.0–46.7) | 39.4 (32.0–45.7) | 42.0 (32.6–44.9) | .98 |
| COPD | 29.2 (24.1–34.2) | 29.2 (25.0–33.2) | 30.6 (23.3–33.8) | 29.2 (24.6–34.2) | 28.4 (24.8–36.3) | .99 |
| Cerebrovascular accident/TIA | 16.8 (13.3–19.6) | 16.8 (13.7–20.2) | 16.1 (13.0–19.1) | 16.4 (12.3–19.3) | 17.6 (16.4–20.5) | .57 |
| Dialysis | 2.7 (1.6–4.0) | 3.1 (2.4–3.9) | 2.1 (1.2–4.0) | 2.7 (1.6–3.9) | 2.6 (1.8–4.2) | .78 |
| Renal insufficiency | 19.5 (11.6–26.9) | 23.1 (13.2–33.9) | 22.7 (16.1–27.6) | 11.8 (9.6–23.6) | 16.1 (11.6–22.2) | .05 |
| History of ischemia† | 58.8 (50.9–63.5) | 58.9 (50.2–62.5) | 58.3 (50.6–62.4) | 57.3 (48.3–66.6) | 60.4 (55.0–63.9) | .69 |
| Smoking | 10.1 (5.5–12.8) | 10.1 (5.2–13.5) | 10.5 (7.0–12.5) | 11.3 (6.2–13.8) | 9.5 (5.4–10.6) | .67 |
| Vital signs | ||||||
| Mean systolic blood pressure, median (quartiles), mm Hg | 141.6 (137.9–146.0) | 145.0 (138.9–147.3) | 141.6 (137.2–146.2) | 140.3 (138.3–144.4) | 141.1 (139.2–144.5) | .70 |
| Admission laboratory test results | ||||||
| Mean creatinine, median (quartiles), mg/dL | 1.6 (1.5–1.7) | 1.6 (1.5–1.8) | 1.7 (1.6–1.8) | 1.6 (1.4–1.7) | 1.6 (1.6–1.6) | .40 |
| Mean BUN, median (quartiles), mg/dL | 29.7 (28.7–31.6) | 30.9 (29.8–32.6) | 29.5 (29.1–32.6) | 29.1 (27.6–30.7) | 29.2 (28.1–30.3) | .09 |
| Mean BNP, median (quartiles), mg/dL | 1216.6 (1017.1–1573.4) | 1129.2 (955.3–1465.0) | 1222.8 (1126.9–1550.6) | 1124.3 (895.4–1890.7) | 1286.0 (1116.0–1826.8) | .29 |
| Discharge laboratory test results | ||||||
| Mean creatinine, median (quartiles), mg/dL | 1.7 (1.5–1.8) | 1.6 (1.5–1.8) | 1.7 (1.7–1.9) | 1.6 (1.3–1.7) | 1.6 (1.5–1.7) | .10 |
| Weight change, mean, kg | 2.5 (1.6–2.9) | 2.4 (1.2–2.7) | 2.4 (2.0–2.9) | 2.6 (1.6–3.0) | 2.4 (1.0–2.7) | .96 |
| Hospital characteristics | ||||||
| Heart failure disease management referrals, % | 5.4 (0.0–16.0) | 12.4 (1.3–37.5) | 5.9 (0.73–13.0) | 0.0 (0.0–12.6) | 5.4 (0.5–16.0) | .10 |
| Discharge instructions (%) | 95.8 (90.5–98.1) | 95.9 (90.2–98.2) | 96.0 (90.5–99.0) | 96.8 (92.6–98.2) | 94.4 (90.5–97.4) | .85 |
| β-Blocker for LVSD, % | 97.6 (95.0–99.0) | 97.8 (96.0–99.0) | 97.0 (95.4–98.7) | 97.7 (93.3–100.0) | 97.6 (96.6–98.6) | .97 |
| ACE inhibitor/ARB for LVSD (%) | 96.2 (92.5–98.9) | 97.3 (93.8–100.0) | 96.7 (90.0–100.0) | 96.0 (93.3–98.9) | 94.4 (91.9–97.3) | .32 |
| Length of stay, median (quartiles), d | 4.0 (4.0–5.0) | 4.0 (4.0–4.0) | 4.0 (4.0–5.0) | 4.0 (3.0–4.0) | 4.0 (4.0–5.0) | .33 |
| Teaching hospital, % | 67.1 | 58.8 | 55.6 | 72.2 | 82.4 | .31 |
| Rural setting, % | 4.3 | 5.9 | 0 | 11.1 | 0 | .51 |
| Cardiac intensive care unit, % | 74.6 | 68.8 | 70.6 | 78.6 | 81.3 | .85 |
| Cardiac catheterization lab, % | 88.9 | 81.3 | 88.2 | 92.9 | 93.8 | .76 |
| Number of beds, median (quartiles) | 370.0 (217.0–555.0) | 328.0 (194.0–428.0) | 339.5 (222.0–601.0) | 324.5 (175.0–575.0) | 465.0 (372.0–531.0) | .34 |
| Annual discharges, median (quartiles) | ||||||
| Medicare | 6534 (4534–9341) | 6534 (3280–8296) | 6061 (4556–10,661) | 5211 (3328–9378) | 8490 (6131–10,555) | .22 |
| Medicaid | 2715 (1281–4837) | 2209 (1027–4837) | 2678 (1366–5191) | 2408 (1311–4747) | 4364 (2367–5262) | .44 |
| US geographic region, %‡ | .81 | |||||
| West | 18.6 | 17.7 | 22.2 | 16.7 | 17.7 | |
| South | 32.9 | 29.4 | 44.4 | 38.9 | 17.7 | |
| Midwest | 21.4 | 17.7 | 16.7 | 16.7 | 35.3 | |
| Northeast | 27.1 | 35.3 | 16.7 | 27.8 | 29.4 | |
| Cardiologists per 100,000 | 5.7 (4.8–7.7) | 7.2 (5.0–7.9) | 5.3 (4.4–6.1) | 6.2 (5.1–8.1) | 5.6 (4.8–6.8) | .43 |
| Prescription drug effectiveness, % | ||||||
| Post–MI β-blocker prescription filled | ||||||
| 1 to 6 months | 84.0 (80.6–88.4) | 84.9 (82.4–88.8) | 84.4 (82.1–88.8) | 83.9 (79.8–86.2) | 82.9 (78.6–88.8) | .85 |
| 7 to 12 months | 79.2 (73.3–82.6) | 79.3 (76.5–81.5) | 79.4 (75.3–82.1) | 80.8 (75.5–84.3) | 74.2 (72.3–81.8) | .42 |
| ACE inhibitor/ARB prescription filled§ | 74.3 (72.6–76.4) | 74.8 (72.7–76.4) | 74.1(72.2–76.7) | 74.1 (72.6–76.5) | 74.5 (71.8–76.3) | .97 |
Abbreviations: ACE, angiotensin-converting-enzyme; ARB, angiotensin II receptor blocker; COPD, chronic obstructive pulmonary disease; BNP, B-type natriuretic peptide; BUN, blood urea nitrogen; LVSD, left ventricular systolic dysfunction; MI, myocardial infarction; TIA, transient ischemic attack.
History of ischemia includes coronary artery disease, prior myocardial infarction, or prior revascularization (ie, percutaneous coronary intervention or coronary artery bypass graft surgery).
Best quartile, −21.0% to −8.8% (n = 17); quartile 2, −8.7% to −5.8% (n = 18); quartile 3, −5.5% to −0.9% (n = 18); worst quartile, 0.2% to 15.5% (n = 17).
US geographic regions include the following states, with weights shown in parentheses: Northeast (19) includes Connecticut (3), Massachusetts (3), New Jersey (2), New York (5), and Pennsylvania (6). Midwest (15) includes Illinois (1), Indiana (2), Kansas (2), Michigan (1), Missouri (3), Ohio (4), South Dakota (1), and Wisconsin (1). South (23) includes Alabama (2), Florida (4), Georgia (1), Kentucky (1), Louisiana (2), Mississippi (1), North Carolina (1), Oklahoma (1), South Carolina (2), Tennessee (3), Texas (3), Virginia (2). West (13) includes Alaska (1), California (3), Colorado (3), Hawaii (1), Idaho (1), New Mexico (1), Nevada (1), and Washington (2).
For patients with diabetes mellitus only.