Rate differences and net clinical risk of major event by frequency of use of low-dose aspirin in a 60-day follow-up period of NHI 2000†
| Haemorrhage (n=94) | Ischaemia (n=624) | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Use of low-dose aspirin | Rate difference‡ | Use of low-dose aspirin | Rate difference‡ | ||||||
| Characteristic | <20% | ≥80% | Crude (%) | Adjusted (%)¶ | <20% | ≥80% | Crude (%) | Adjusted (%)¶ | Adjusted net clinical risk (%)§¶ (95% CI) |
| n (%) | n (%) | ||||||||
| All patients | 11 (0.09) | 83 (0.32) | 0.23 | 0.24*** | 25 (0.21) | 599 (2.30) | −2.09 | −2.00*** | 2.24*** (2.03 to 2.48) |
| Age (years) | |||||||||
| < 65 | 5 (0.06) | 40 (0.23) | 0.17 | 0.19*** | 8 (0.09) | 322 (1.87) | −1.78 | −1.70*** | 1.89*** (1.67 to 2.12) |
| ≥65 | 6 (0.18) | 43 (0.48) | 0.30 | 0.37*** | 17 (0.52) | 277 (3.12) | −2.60 | −2.56*** | 2.93*** (2.42 to 3.43) |
| Sex | |||||||||
| Male | 7 (0.12) | 51 (0.37) | 0.25 | 0.29*** | 13 (0.23) | 366 (2.67) | −2.44 | −2.43*** | 2.72*** (2.34 to 3.07) |
| Female | 4 (0.06) | 32 (0.26) | 0.20 | 0.24** | 12 (0.19) | 233 (1.88) | −1.69 | −1.57*** | 1.81*** (1.49 to 2.13) |
| Place of insurance registry | |||||||||
| Northern | 3 (0.06) | 41 (0.32) | 0.26 | 0.32*** | 11 (0.21) | 325 (2.51) | −2.30 | −2.26*** | 2.58*** (2.25 to 2.91) |
| Central | 3 (0.09) | 18 (0.30) | 0.21 | 0.21* | 4 (0.12) | 101 (1.69) | −1.57 | −1.44*** | 1.65*** (1.22 to 2.09) |
| Southern | 5 (0.16) | 24 (0.37) | 0.21 | 0.21 | 10 (0.32) | 156 (2.41) | −2.09 | −1.99*** | 2.20*** (1.68 to 2.73) |
| Eastern | 0 | 0 | 0.00 | – | 0 (0.00) | 17 (2.53) | −2.53 | – | – |
| Urbanisation | |||||||||
| Rural area or satellite city | 4 (0.11) | 27 (0.42) | 0.31 | 0.43** | 5 (0.14) | 159 (2.50) | −2.36 | −2.23*** | 2.66*** (2.18 to 3.14) |
| Metropolis | 7 (0.08) | 56 (0.28) | 0.20 | 0.20*** | 20 (0.23) | 440 (2.23) | −2.00 | −1.92*** | 2.12*** (1.87 to 2.38) |
| Hypertension | |||||||||
| No | 7 (0.09) | 35 (0.32) | 0.23 | 0.28** | 10 (0.12) | 281 (2.54) | −2.42 | −2.28*** | 2.56*** (2.22 to 2.909) |
| Yes | 4 (0.10) | 48 (0.32) | 0.22 | 0.27*** | 15 (0.38) | 318 (2.11) | −1.73 | −1.65*** | 1.91*** (1.56 to 2.26) |
| Diabetes | |||||||||
| No | 6 (0.06) | 53 (0.28) | 0.22 | 0.24*** | 22 (0.21) | 449 (2.37) | −2.16 | −2.06*** | 2.30*** (2.04 to 2.57) |
| Yes | 5 (0.30) | 30 (0.42) | 0.12 | 0.27 | 3 (0.18) | 150 (2.10) | −1.92 | −1.89*** | 2.15*** (1.64 to 2.67) |
| Atrial fibrillation | |||||||||
| No | 11 (0.09) | 82 (0.32) | 0.23 | 0.24*** | 25 (0.21) | 588 (2.30) | −2.09 | −2.00*** | 2.24*** (2.00 to 2.48) |
| Yes | 0 | 1 (0.20) | 0.20 | – | 0 (0.00) | 11 (2.24) | −2.24 | – | – |
| Congestive heart failure | |||||||||
| No | 10 (0.09) | 78 (0.32) | 0.23 | 0.25*** | 24 (0.21) | 573 (2.33) | −2.12 | −2.03*** | 2.28*** (2.06 to 2.50) |
| Yes | 1 (0.27) | 5 (0.34) | 0.07 | – | 1 (0.27) | 26 (1.78) | −1.51 | – | – |
| Peripheral artery disease | |||||||||
| No | 11 (0.09) | 83 (0.32) | 0.23 | 0.24*** | 25 (0.21) | 592 (2.29) | −2.08 | −2.00*** | 2.25*** (2.02 to 2.48) |
| Yes | 0 | 0 | 0.00 | – | 0 | 7 (2.51) | −2.51 | – | – |
| Peptic ulcer | |||||||||
| No | 10 (0.10) | 70 (0.31) | 0.21 | 0.23*** | 20 (0.19) | 539 (2.37) | −2.18 | −2.10*** | 2.32*** (2.08 to 2.57) |
| Yes | 1 (0.06) | 13 (0.39) | 0.33 | 0.53* | 5 (0.31) | 60 (1.81) | −1.50 | −1.37*** | 1.90*** (11.9 to 2.61) |
| Transient cerebral ischaemia | |||||||||
| No | 11 (0.09) | 82 (0.32) | 0.23 | 0.24*** | 25 (0.21) | 589 (2.32) | −2.11 | −2.02*** | 2.26*** (2.03 to 2.50) |
| Yes | 0 | 1 (0.13) | 0.13 | – | 0 | 10 (1.35) | −1.35 | – | – |
| Ischaemic heart disease | |||||||||
| No | 11 (0.10) | 75 (0.31) | 0.21 | 0.24*** | 23 (0.20) | 578 (2.39) | −2.19 | −2.10*** | 2.34*** (2.11 to 2.57) |
| Yes | 0 | 8 (0.41) | 0.41 | – | 2 (0.39) | 21 (1.09) | −0.70 | – | – |
| Charlson Comorbidity Index score | |||||||||
| <3 | 8 (0.07) | 64 (0.30) | 0.23 | 0.25*** | 22 (0.21) | 496 (2.30) | −2.09 | −2.03*** | 2.28*** (2.04 to 2.53) |
| ≥3 | 3 (0.23) | 19 (0.42) | 0.19 | 0.29 | 3 (0.23) | 103 (2.29) | −2.06 | −1.91*** | 2.20*** (1.50 to 2.91) |
| Use of anticoagulants | |||||||||
| No | 11 (0.09) | 81 (0.32) | 0.23 | 0.24*** | 24 (0.21) | 545 (2.14) | −1.93 | −1.82*** | 2.06*** (1.84 to 2.28) |
| Yes | 0 | 2 (0.32) | 0.32 | – | 1 (0.25) | 54 (8.68) | −8.43 | – | – |
| Use of antilipemic agents | |||||||||
| No | 11 (0.10) | 74 (0.34) | 0.24 | 0.26*** | 21 (0.19) | 576 (2.64) | −2.45 | −2.29*** | 2.54*** (2.30 to 2.79) |
| Yes | 0 | 9 (0.21) | 0.21 | – | 4 (0.52) | 23 (0.54) | −0.02 | – | – |
| Use of NSAIDs | |||||||||
| No | 4 (0.06) | 57 (0.29) | 0.23 | 0.23*** | 13 (0.20) | 537 (2.74) | −2.54 | −2.61*** | 2.84*** (2.57 to 3.11) |
| Yes | 7 (0.12) | 26 (0.40) | 0.28 | 0.37** | 12 (0.21) | 62 (0.96) | −0.75 | −0.74*** | 1.07*** (0.67 to 1.47) |
| Use of PPIs | |||||||||
| No | 10 (0.09) | 78 (0.30) | 0.21 | 0.22*** | 25 (0.21) | 594 (2.30) | −2.09 | −2.01*** | 2.23*** (2.00 to 2.46) |
| Yes | 1 (0.31) | 5 (2.00) | 1.69 | – | 0 | 5 (2.00) | −2.00 | – | – |
| Use of antidepressants | |||||||||
| No | 11 (0.10) | 82 (0.33) | 0.23 | 0.25*** | 23 (0.20) | 592 (2.36) | −2.16 | −2.09*** | 2.34*** (2.11 to 2.57) |
| Yes | 0 | 1 (0.10) | 0.10 | – | 2 (0.29) | 7 (0.67) | −0.38 | – | – |
| Use of corticosteroids | |||||||||
| No | 11 (0.10) | 80 (0.32) | 0.22 | 0.25*** | 23 (0.21) | 591 (2.38) | −2.17 | −2.12*** | 2.37*** (2.14 to 2.60) |
| Yes | 0 | 3 (0.23) | 0.23 | – | 2 (0.16) | 8 (0.62) | −0.46 | – | – |
– indicates insufficient observations to compute bootstrap SEs.
*p<0.05; **p<0.01; ***p<0.001.
†Major event includes haemorrhage (gastrointestinal haemorrhage or haemorrhagic stroke) or ischaemia (ischaemic stroke or acute myocardial infarction).
‡Difference in rate of haemorrhage was calculated as (haemorrhage rateuse of low-dose aspirin ≥80%)−(haemorrhage rateuse of low-dose aspirin <20%); difference in rate of ischaemia was calculated as (ischaemia rateuse of low-dose aspirin <20%)−(ischaemia rateuse of low-dose aspirin ≥80%).
§Net clinical risk=[(haemorrhage rateuse of low-dose aspirin ≥80%)−(haemorrhage rateuse of low-dose aspirin <20%)]−[(ischaemia rateuse of low-dose aspirin <20%)−(ischaemia rateuse of low-dose aspirin ≥80%)].
¶Adjusting all variables listed in table 1. For subgroup analyses, all variables, except the variable classified, listed in table 1 were adjusted. Bootstrapping analysis was conducted with 1000 time replications to compute differences in predicted adjusted rates and bootstrap SEs.
NHI, National Health Insurance; NSAID, non-steroidal anti-inflammatory drug; PPI, proton pump inhibitor.