Table 2. Incidence rates of cancer in LTRA users and non-users.
| All patients | LTRA non-users | IR | LTRA users | IRR [95% CI] | aIRR [95% CI] | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| N | Cancer | PY | IR | N | Cancer | PY | N | Cancer | PY | IR | ||||
| Whole study population Stratified analyses | 25110 | 1197 | 100593.2 | 11.9 | 20925 | 1104 | 84593.3 | 13.1 | 4185 | 93 | 15999.9 | 5.8 | 0.45 [0.39–0.51]*** | 0.41 [0.36–0.47]*** |
| Sex | ||||||||||||||
| Female | 14934 | 625 | 61015.7 | 10.2 | 12445 | 585 | 51404.0 | 11.4 | 2489 | 40 | 9611.7 | 4.2 | 0.37 [0.30–0.44]*** | 0.34 [0.28–0.41]*** |
| Male | 10176 | 572 | 39577.5 | 14.5 | 8480 | 519 | 33189.3 | 15.6 | 1696 | 53 | 6388.2 | 8.3 | 0.53 [0.44–0.64]*** | 0.49 [0.41–0.58]*** |
| Age | ||||||||||||||
| Age ≤40 | 9559 | 109 | 43348.8 | 2.5 | 7936 | 104 | 36702.5 | 2.8 | 1623 | 5 | 6646.3 | 0.8 | 0.27 [0.19–0.36]*** | 0.27 [0.20–0.37]*** |
| 40< Age ≤65 | 11061 | 620 | 43523.3 | 14.2 | 9247 | 570 | 36702.9 | 15.5 | 1814 | 50 | 6820.4 | 7.3 | 0.47 [0.39–0.57]*** | 0.45 [0.37–0.55]*** |
| Age >65 | 4490 | 468 | 13721.1 | 34.1 | 3742 | 430 | 11187.9 | 38.4 | 748 | 38 | 2533.2 | 15.0 | 0.39 [0.30–0.51]*** | 0.38 [0.29–0.50]*** |
| Residency | ||||||||||||||
| Northern Taiwan | 13836 | 589 | 56174.4 | 10.5 | 11191 | 530 | 46127.2 | 11.5 | 2645 | 59 | 10047.2 | 5.9 | 0.51 [0.43–0.60]*** | 0.43 [0.37–0.50]*** |
| Other areas | 11274 | 608 | 44418.8 | 13.7 | 9734 | 574 | 38466.1 | 14.9 | 1540 | 34 | 5952.7 | 5.7 | 0.38 [0.30–0.48]*** | 0.38 [0.30–0.47]*** |
| Monthly income | ||||||||||||||
| ≤NT$24000 | 12290 | 759 | 47025.8 | 16.1 | 10412 | 708 | 39915.9 | 17.7 | 1878 | 51 | 7109.9 | 7.2 | 0.40 [0.33–0.49]*** | 0.36 [0.30–0.44]*** |
| >NT$24000 | 12820 | 438 | 53567.4 | 8.2 | 10513 | 396 | 44677.4 | 8.9 | 2307 | 42 | 8890.0 | 4.7 | 0.53 [0.45–0.64]*** | 0.48 [0.41–0.57]*** |
| Marriage status | ||||||||||||||
| Married | 16049 | 921 | 64873.1 | 14.2 | 13409 | 845 | 54554.7 | 15.5 | 2640 | 76 | 10318.4 | 7.4 | 0.48 [0.41–0.56]*** | 0.44 [0.38–0.51]*** |
| Not married | 9061 | 276 | 35720.1 | 7.7 | 7516 | 259 | 30038.6 | 8.6 | 1545 | 17 | 5681.5 | 3.0 | 0.35 [0.27–0.45]*** | 0.31 [0.24–0.39]*** |
| Education level | ||||||||||||||
| Elementary school or lower | 9616 | 731 | 34513.9 | 21.2 | 8131 | 680 | 29182.4 | 23.3 | 1485 | 51 | 5331.6 | 9.6 | 0.41 [0.33–0.51]*** | 0.39 [0.32–0.48]*** |
| High school | 11136 | 348 | 47369.8 | 7.3 | 9310 | 319 | 40247.0 | 7.9 | 1826 | 29 | 7122.8 | 4.1 | 0.51 [0.42–0.63]*** | 0.43 [0.35–0.52]*** |
| College or higher | 4358 | 118 | 18709.5 | 6.3 | 3484 | 105 | 15163.9 | 6.9 | 874 | 13 | 3545.6 | 3.7 | 0.53 [0.39–0.71]*** | 0.42 [0.32–0.55]*** |
| With comorbidity | ||||||||||||||
| No (mCCI score = 0) | 16500 | 685 | 71023.6 | 9.6 | 13750 | 636 | 59945.8 | 10.6 | 2750 | 49 | 11077.8 | 4.4 | 0.42 [0.35–0.50]*** | 0.38 [0.32–0.44]*** |
| Yes (mCCI score ≥ 1) | 8610 | 512 | 29569.6 | 17.3 | 7175 | 468 | 24647.5 | 19.0 | 1435 | 44 | 4922.1 | 8.9 | 0.47 [0.38–0.58]*** | 0.45 [0.37–0.55]*** |
The subjects were followed from a year after the index date to either development of cancer, death or the end of 2011, whichever came first.
The incidence rate (IR) is expressed as incident cancer per 1000 patient-years. The IRs of cancer in LTRA users and non-users were compared by estimating the incidence rate ratio (IRR) using Poisson regression and adjusted IRR (aIRR) using multivariable Poisson regression after adjusting for age, residency, income level, marriage status, education level and the presence of various comorbidities (except for the variable used for stratification).
*P < 0.05; **P < 0.01; ***P < 0.0001.
Abbreviation: N = number of patients; Cancer = number of patients with incident cancer; PY = total patient-years of follow-up; CI = confidence interval.