Table 4.

Among TT-exposed group, adjusted IRR of prostate cancer by TT therapy characteristics.

CharacteristicsCasesNPerson-yearsUnadjusted IRR (95% CI)Adjusted IRR (95% CI)
Time on testosterone: all medicationsa
 <3 months17239,18488,374ReferentReferent
 3–6 months6716,52936,9700.93 (0.70–1.23)0.97 (0.73–1.29)
 6 or more months9119,08051,5710.91 (0.70–1.17)0.97 (0.75–1.26)
Number of testosterone fills of first medicationb
 1 to 221146,602106,212ReferentReferent
 3 to 77918,32142,9181.17 (0.90–1.52)1.14 (0.69–1.49)
 8 or more469,86927,7841.20 (0.87–1.65)1.14 (0.83–1.56)
Route of administrationc
 Patch20541,037102,5310.85 (0.68–1.06)0.86 (0.69–1.08)
 Injection12533,40073,408ReferentReferent
Change in testosterone level on therapyd
 Decrease62,2686,417ReferentReferent
 Increase276,48018,8771.53 (0.63–3.71)1.40 (0.56–3.49)
Change in testosterone level on therapy (based on quartiles)e
 Decrease62,2686,4170.60 (0.22–1.66)0.64 (0.23–1.80)
 0–91122,1016,1311.26 (0.55–2.92)1.13 (0.48–2.68)
 92–286102,1926,446ReferentReferent
 287+52,1876,3000.51 (0.17–1.50)0.50 (0.17–1.49)
  • aAdjusted for age, preindex time, DCI, preindex annual flag, preindex T test, preindex PSA test, index date year.

  • bAdjusted for age, route of administration, preindex time, DCI, preindex annual flag, preindex T test, preindex PSA test, index date year.

  • cOther administrations excluded (N = 356); adjusted for time on T, age, preindex time, DCI, preindex annual flag (1 year), preindex PSA test, preindex T test, index date year.

  • dAdjusted for preindex T result, age, time between tests, DCI, preindex PSA test, index date year, urinary symptoms, other prostate disease, inflammatory prostate, benign prostatic hyperplasia, hypogonadism, osteoporosis, diabetes (complicated and uncomplicated), liver failure.

  • eAdjusted for preindex T result, age, time between tests, preindex annual flag (1 year), DCI, preindex PSA test, index date year, preindex specialist flag, urinary symptoms, other prostate disease, inflammatory prostate, benign prostatic hyperplasia, hypogonadism, family history of prostate cancer, psychosexual dysfunction, osteoporosis, diabetes (complicated and uncomplicated), liver failure.