Table 2

Crude and adjusted HRs and associated 95% CIs of PCCRC* after one, two, three, four and five colonoscopies, comparing patients with type 2 diabetes (T2D)† with non-T2D

Crude HR (95% CI)Adjusted HR‡ (95% CI)
First colonoscopy1.89 (1.60 to 2.24)1.44 (1.21 to 1.72)
Sex
 Female2.07 (1.63 to 2.63)1.52 (1.18 to 1.95)
 Male1.69 (1.34 to 2.13)1.38 (1.08 to 1.76)
Age at colonoscopy
 0–591.83 (1.02 to 3.28)1.77 (0.95 to 3.30)
 60–691.49 (1.08 to 2.04)1.80 (1.29 to 2.52)
 70+1.25 (1.02 to 1.54)1.29 (1.04 to 1.60)
Medication§
 Insulin2.42 (1.81 to 3.24)2.15 (1.58 to 2.92)
 Metformin1.64 (1.30 to 2.06)1.46 (1.14 to 1.87)
 Sulfonylureas1.98 (1.51 to 2.60)1.53 (1.15 to 2.03)
 Other antidiabetic drugsN/AN/A
PCCRC stage at diagnosis
 Localised1.52 (1.14 to 2.03)1.21 (0.89 to 1.64)
 Regional1.47 (0.98 to 2.21)1.22 (0.80 to 1.87)
 Metastatic2.24 (1.60 to 3.13)1.73 (1.22 to 2.47)
 Unknown2.81 (2.01 to 3.92)1.78 (1.25 to 2.53)
 Second colonoscopy¶1.45 (0.94 to 2.23)1.18 (0.75 to 1.85)
Sex
 Female1.20 (0.61 to 2.38)0.95 (0.47 to 1.92)
 Male1.66 (0.94 to 2.93)1.44 (0.80 to 2.60)
Age at colonoscopy
 0–592.44 (0.74 to 8.03)3.12 (0.91 to 10.69)
 60–691.69 (0.83 to 3.41)1.55 (0.74 to 3.24)
 70+0.85 (0.4 to 1.58)0.85 (0.45 to 1.62)
Medication§
 Insulin1.84 (0.90 to 3.74)1.63 (0.79 to 3.39)
 Metformin1.69 (1.00 to 2.86)1.47 (0.85 to 2.55)
 Sulfonylureas1.19 (0.56 to 2.54)0.95 (0.44 to 2.06)
 Other antidiabetic drugsN/AN/A
PCCRC stage at diagnosis
 Localised1.08 (0.50 to 2.35)1.02 (0.46 to 2.26)
 Regional1.51 (0.53 to 4.27)1.24 (0.41 to 3.71)
 Metastatic0.95 (0.29 to 3.09)0.79 (0.23 to 2.68)
 Unknown2.49 (1.21 to 5.11)1.62 (0.77 to 3.42)
Third colonoscopy**1.12 (0.54 to 2.31)0.78 (0.37 to 1.67)
Sex
 Female0.75 (0.18 to 3.13)0.68 (0.16 to 2.93)
 Male1.27 (0.55 to 2.99)0.83 (0.34 to 2.)
Age at colonoscopy
 0–59N/AN/A
 60–692.59 (1.06 to 6.34)1.92 (0.71 to 5.20)
 70+0.37 (0.09 to 1.52)0.32 (0.07 to 1.34)
Medication§
 Insulin1.02 (0.25 to 4.15)0.66 (0.16 to 2.81)
 Metformin1.31 (0.53 to 3.23)0.99 (0.38 to 2.56)
 Sulfonylureas0.74 (0.18 to 2.98)0.54 (0.13 to 2.25)
 Other antidiabetic drugsN/AN/A
PCCRC stage at diagnosis
 Localised0.54 (0.13 to 2.23)0.51 (0.12 to 2.14)
 Regional1.46 (0.18 to 11.71)1.23 (0.15 to 10.29)
 Metastatic1.20 (0.28 to 5.15)0.61 (0.13 to 2.80)
 Unknown2.72 (0.77 to 9.56)1.62 (0.43 to 6.02)
Fourth colonoscopy††1.19 (0.36 to 3.91)1.18 (0.35 to 3.98)
Fifth colonoscopy‡‡0.83 (0.11 to 6.32)0.81 (0.10 to 6.41)

  • Denmark, 1995–2015.

  • *Colorectal cancer diagnosed within >6 to 36 months after a negative colonoscopy.

  • †Diagnosis of T2D recorded in the Danish National Patient Registry before or within 90 days after a first-time colonoscopy and/or at least one redeemed prescription for a glucose-lowering drug recorded in the Danish National Health Service Prescription Database before or within 90 days a first-time colonoscopy. Patients with diabetes diagnoses and prescriptions recorded before age 30 not included as these were considered to represent patients with type 1 diabetes.

  • ‡Adjusted for age group, sex, year of colonoscopy and presence of chronic obstructive pulmonary disease, atrial fibrillation/flutter, cardiovascular diseases, renal diseases, alcohol-related diseases diverticular diseases, obesity and familial hereditary colorectal cancer syndromes.

  • §Comparing patients with T2D with prescriptions for the given medication before the relevant colonoscopy with patients with non-T2D. Patients T2D are allowed to be included in multiple medication groups.

  • ¶The first subsequent colonoscopy recorded more than 6 months after the first-time colonoscopy.

  • **The first colonoscopy recorded more than 6 months after the second colonoscopy.

  • ††The first colonoscopy recorded more than 6 months after the third colonoscopy.

  • ‡‡The first colonoscopy recorded more than 6 months after the fourth colonoscopy.

  • PCCRC, postcolonoscopy colorectal cancer; T2D, type 2 diabetes.