Table 1. Baseline characteristics of study subjects before and after propensity score matching, by pentoxifylline usea.
| Before matching | Propensity score-matched | |||||||
|---|---|---|---|---|---|---|---|---|
| Pentoxifylline users (n = 2336) | Pentoxifylline nonusers (n = 11781) | P | SD | Pentoxifylline users (n = 2118) | Pentoxifylline nonusers (n = 6354) | P | SD | |
| Age, mean (SD), y | 64.0 (13.1) | 64.8 (13.1) | 0.38 | 0.062 | 64.5 (13.0) | 64.2 (13.1) | 0.29 | 0.027 |
| Age, group, y | 0.006 | 0.09 | ||||||
| 20–44 | 171 (7.3) | 861 (7.3) | 0.001 | 145 (6.9) | 510 (8) | 0.045 | ||
| 45–64 | 970 (41.5) | 4,450 (37.8) | 0.077 | 848 (40) | 2,488 (39.2) | 0.018 | ||
| 65–74 | 641 (27.4) | 3,510 (29.8) | 0.052 | 596 (28.1) | 1,881 (29.6) | 0.032 | ||
| 75–100 | 554 (23.7) | 2,960 (25.1) | 0.033 | 529 (25) | 1,475 (23.2) | 0.041 | ||
| Gender | ||||||||
| Male | 1,225 (52.4) | 5,352 (45.4) | <0.001 | 0.141 | 1,037 (49) | 3,198 (50.3) | 0.28 | 0.027 |
| Comorbid conditions within 3 y before the index date | ||||||||
| Diabetes | 1,401 (60) | 6,747 (57.3) | 0.02 | 0.055 | 1,247 (58.9) | 3,759 (59.2) | 0.82 | 0.006 |
| MI | 613 (26.2) | 3,067 (26) | 0.83 | 0.005 | 558 (26.4) | 1,673 (26.3) | 0.99 | 0.001 |
| Stroke | 492 (21.1) | 2,218 (18.8) | 0.01 | 0.056 | 418 (19.7) | 1,246 (19.6) | 0.90 | 0.003 |
| Cancer | 170 (7.3) | 1,002 (8.5) | 0.049 | 0.046 | 166 (7.8) | 459 (7.2) | 0.35 | 0.023 |
| Charlson Comorbidity Index score | 0.19 | 0.83 | ||||||
| <3 | 794 (34) | 4,216 (35.8) | 0.038 | 740 (34.9) | 2,223 (35) | 0.001 | ||
| 4–5 | 857 (36.7) | 4,280 (36.3) | 0.007 | 770 (36.4) | 2,347 (36.9) | 0.012 | ||
| >5 | 685 (29.3) | 3,285 (27.9) | 0.032 | 608 (28.7) | 1,784 (28.1) | 0.014 | ||
| Mean (SD) | 4.5 (2.2) | 4.4 (2.3) | 0.09 | 0.03 | 4.5 (2.2) | 4.5 (2.2) | 0.99 | 0.001 |
| Nephrologist visits within 3 y before the index date | <0.001 | 0.81 | ||||||
| 0 | 366 (15.7) | 2,504 (21.3) | 0.144 | 365 (17.2) | 1,079 (17) | 0.007 | ||
| 1–6 | 536 (23) | 3,097 (26.3) | 0.078 | 515 (24.3) | 1,511 (23.8) | 0.013 | ||
| >6 | 1,434 (61.4) | 6,180 (52.5) | 0.181 | 1,238 (58.5) | 3,764 (59.2) | 0.016 | ||
| Anti-hypertensive agents used | ||||||||
| ACEI | 833 (35.7) | 5,081 (43.1) | <0.001 | 0.153 | 794 (37.5) | 2,387 (37.6) | 0.95 | 0.002 |
| ARB | 1,847 (79.1) | 8,460 (71.8) | <0.001 | 0.169 | 1,634 (77.2) | 4,907 (77.2) | 0.94 | 0.002 |
| Beta-blockers | 1,093 (46.8) | 4,960 (42.1) | <0.001 | 0.094 | 947 (44.7) | 2,902 (45.7) | 0.44 | 0.019 |
| Calcium channel blockers | 1,731 (74.1) | 8,153 (69.2) | <0.001 | 0.109 | 1,532 (72.3) | 4,653 (73.2) | 0.42 | 0.020 |
| Diuretics | 1,549 (66.3) | 7,752 (65.8) | 0.64 | 0.011 | 1,424 (67.2) | 4,242 (66.8) | 0.69 | 0.010 |
| Insulin | 753 (32.2) | 3,322 (28.2) | <0.001 | 0.088 | 642 (30.3) | 1,931 (30.4) | 0.95 | 0.002 |
| Statin | 595 (25.5) | 2,363 (20.1) | <0.001 | 0.129 | 467 (22.1) | 1,449 (22.8) | 0.47 | 0.018 |
| Aspirin | 636 (27.2) | 2,606 (22.1) | <0.001 | 0.119 | 528 (24.9) | 1,611 (25.4) | 0.70 | 0.010 |
| Acetaminophen | 1,173 (50.2) | 5,863 (49.8) | 0.69 | 0.009 | 1,050 (49.6) | 3,172 (49.9) | 0.78 | 0.007 |
| NSAIDs | ||||||||
| COX-2 inhibitors | 106 (4.5) | 544 (4.6) | 0.87 | 0.004 | 96 (4.5) | 292 (4.6) | 0.90 | 0.003 |
| Non-COX-2 inhibitors | 858 (36.7) | 4,446 (37.7) | 0.36 | 0.021 | 777 (36.7) | 2,351 (37) | 0.79 | 0.007 |
| Geographic location | <0.001 | 0.56 | ||||||
| Northern | 1,146 (49.1) | 4,515 (38.3) | 0.218 | 1,089 (51.4) | 3,157 (49.7) | 0.035 | ||
| Middle | 794 (34) | 2,581 (21.9) | 0.272 | 633 (29.9) | 1,968 (31) | 0.024 | ||
| Southern | 377 (16.1) | 4,360 (37) | 0.486 | 377 (17.8) | 1,176 (18.5) | 0.018 | ||
| Eastern or other islands | 19 (0.8) | 325 (2.8) | 0.147 | 19 (0.9) | 53 (0.8) | 0.007 | ||
| Propensity score | 0.209(0.083) | 0.157(0.082) | <0.001 | 0.636 | 0.194(0.012) | 0.197(0.075) | 0.19 | 0.032 |
Abbreviations: ACEI, angiotensin converting enzyme inhibitor; ARB, angiotensin II receptor blocker; CCI, Charlson comorbidity index; CKD, chronic kidney disease; COX-2, cyclooxygenase -2; NSAID, non-steroidal anti-inflammatory drug; SD, standardized difference. Diuretics included thiazides, loop diuretics, and potassium sparing agents.
aAll of the data are presented as n (%) unless otherwise indicated.