Table 1.
Characteristics of patients who had major elective surgerya
| Preoperative Statin Use |
||
|---|---|---|
| Yes (n = 67,941) | No (n = 145,406) | |
| Demographics and comorbidities | ||
| age, yearsb | 73 (69 to 77) | 74 (70 to 79) |
| age groupsb | ||
| 66 to 70 | 23,343 (34.4) | 42,456 (29.2) |
| 71 to 75 | 22,136 (32.6) | 43,263 (29.8) |
| 76 to 80 | 15,066 (22.2) | 33,470 (23.0) |
| 81 to 85 | 6,003 (8.8) | 18,192 (12.5) |
| 86 to 90 | 1,252 (1.8) | 6,592 (4.5) |
| ≥91 | 141 (0.2) | 1,433 (1.0) |
| female genderb | 23,935 (35.2) | 62,749 (43.2) |
| income quintile | ||
| 1 to 2 (lower) | 27,805 (40.9) | 60,343 (41.5) |
| 3 to 5 (higher) | 40,136 (59.0) | 85,063 (58.5) |
| rural residence | 10,270 (15.1) | 25,278 (17.4) |
| no. of distinct drugs in preceding 1 yearb | ||
| 1 to 5 | 9,635 (14.2) | 44,475 (30.6) |
| 6 to 10 | 27,799 (40.9) | 56,663 (39.0) |
| 11 to 15 | 19,355 (28.5) | 29,425 (20.2) |
| 16 to 20 | 7,872 (11.6) | 10,653 (7.3) |
| 21 to 26 | 2,579 (3.8) | 3,336 (2.3) |
| >26 | 701 (1.0) | 854 (0.6) |
| hypertensionb | 42,946 (63.2) | 75,546 (52.0) |
| cerebrovascular diseaseb | 13,502 (19.9) | 20,024 (13.8) |
| peripheral vascular disease | 4,297 (6.3) | 7,133 (4.9) |
| coronary artery diseaseb | 27,732 (40.8) | 21,962 (15.1) |
| congestive heart failure | 13,232 (19.5) | 23,612 (16.2) |
| diabetesb | 19,803 (29.1) | 25,930 (17.8) |
| chronic kidney diseasec | 15,489 (22.8) | 32,342 (22.2) |
| Medication use in preceding 120 days | ||
| β-blockerb | 36,660 (54.0) | 36,796 (25.3) |
| calcium channel blockerb | 27,263 (40.1) | 37,518 (25.8) |
| potassium-sparing diuretic | 4,367 (6.4) | 9,928 (6.8) |
| non–potassium-sparing diureticb | 21,151 (31.1) | 34,718 (23.9) |
| NSAIDsd | 7,260 (10.7) | 17,206 (11.8) |
| Cox-2 inhibitors | 2,419 (3.6) | 3,727 (2.6) |
| ASAb,d | 14,490 (21.3) | 21,898 (15.1) |
| ARBb | 9,012 (13.3) | 7,604 (5.2) |
| ACEb | 34,852 (51.3) | 40,284 (27.7) |
| anti-platelets other than ASAb | 7,833 (11.5) | 3,663 (2.5) |
| Measures of healthcare access in preceding 3 years | ||
| number of primary care visits | ||
| 0 | 20,747 (30.5) | 42,163 (29.0) |
| 1 to 3 | 40,346 (59.4) | 85,508 (58.8) |
| 4 to 10 | 6,625 (9.8) | 16,728 (11.5) |
| >10 | 223 (0.3) | 1,007 (0.7) |
| number of days in hospitalb | ||
| 0 to 7 | 45,549 (67.0) | 95,331 (65.6) |
| 8 to 14 | 10,593 (15.6) | 21,604 (14.9) |
| 15 to 21 | 5,028 (7.4) | 11,113 (7.6) |
| >21 | 6,771 (10.0) | 17,358 (11.9) |
| number of cardiologist visitsb | 1 (0 to 4) | 0 (0 to 1) 17,132 (11.5) |
| number of cholesterol testsb | 3 (2 to 5) | 1 (0 to 2) |
| number of creatinine laboratory testsb | 4 (2 to 6) | 2 (1 to 4) |
| ≥1 cardiac stress testb | 42,364 (60.1) | 47,714 (32.0) |
| ≥1 echocardiogramb | 41,349 (60.9) | 54,491 (37.5) |
| ≥1 carotid ultrasoundb | 18,885 (27.8) | 22,659 (15.6) |
| Surgical characteristics | ||
| type of surgeryb | ||
| cardiac | 31,678 (46.6) | 30,469 (21.0) |
| vascular | 14,684 (21.6) | 22,561 (15.5) |
| thoracic | 3,633 (5.3) | 10,498 (7.2) |
| abdominal | 14,760 (21.7) | 71,032 (48.9) |
| retroperitoneal | 3,186 (4.7) | 10,846 (7.5) |
| era of surgeryb | ||
| 1995 to 1999 | 11,593 (17.1) | 66,840 (46.0) |
| 2000 to 2004 | 27,574 (40.6) | 49,419 (33.9) |
| 2005 to 2008 | 28,774 (42.4) | 29,147 (20.0) |
aData presented as number (percent) with the exception of age, number of cardiologist visits, number of cholesterol tests, and number of creatinine laboratory tests, which are presented as median (interquartile range). NSAID, nonsteroidal anti-inflammatory drug; ASA, acetylsalicylic acid; ACE, angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker; Cox-2 inhibitor, cyclooxygenase 2 inhibitor.
bStandardized difference between the groups that is >10%. Standardized differences are less sensitive to sample size than traditional hypothesis tests. They provide a measure of the difference between groups divided by the pooled SD. A value >10% is interpreted as a meaningful difference between the groups.55,56
cChronic kidney disease based on administrative data. Serum creatinine values were available for 4% of patients. Estimated GFR (eGFR) was calculated for those with available creatinine data. eGFR before surgery was similar between both groups (statin users, 67 ml/min per 1.73 m2; nonusers, 69 ml/min per 1.73 m2; proportion of patients with an eGFR < 30 ml/min per 1.73 m2: 3% for statin users, 4% for statin nonusers).
dUse based on data for prescriptions filled. Accuracy of measurement is limited by over-the-counter use of these medications.