Table 1

Baseline characteristics of the study cohort in 12 months before the index date

CharacteristicsSID*Inflammatory bowel diseasePsoriasisRheumatoid arthritisSystemic lupus erythematousNon-SID*
N133 33325 17634 66558 97914 513533 332
Percentage or mean±SD
Follow-up period, years2.1±1.82.1±1.92.0±1.82.1±1.82.0±1.82.1±1.9
Age, years50.3±11.847.5±12.049.0±11.853.0±11.347.7±10.850.3±11.8
HPV infection-associated factors
 Sexually active636861607654
 Oral contraceptives1116129910
 Non-oral contraceptives121111
 Smoking9101081110
 Sexually transmitted diseases333353
 Substance abuse0.510.40.410.5
 Alcoholism0.40.40.50.30.30.5
 Receipt of HPV vaccine0.30.30.40.30.30.5
Comorbidities
 Comorbidity score†
 Median (IQR)
0.3±1.2
0 (0–1)
0.5±1.2
0 (0–1)
0.2±0.9
0 (0–0)
0.3±1.1
0 (0–1)
0.7±1.5
0 (0–1)
−0.3±1.2
−1 (−1–0)
 Diabetes11812121021
 Chronic kidney disease3212112
 Liver disease554463
 Prior abnormal Pap smears454353
Medication
 Systemic immunosuppressive drugs‡35132057211
 Systemic steroids382717524614
 Cumulative steroid dose§,
 Median (IQR)
387.5 (940.2)
0 (0–300)
327.0 (928.7)
0 (0–105)
77.6 (333.4)
0 (0–0)
527.0 (1018.3)
105 (0–605)
665.5 (1324.1)
0 (0–750)
52.0 (299.9)
0 (0–0)
 NSAIDs332026583922
Healthcare use
 No of total doctor visits,
 Median (IQR)
9.6±7.0
8 (5–12)
8.5±6.5
7 (4–11)
8.0±6.1
7 (4–10)
10.5±7.1
9 (6–14)
11.3±8.1
9 (6–15)
6.7±5.2
5 (3–9)
 No of visits to a gynaecologist,
 Median (IQR)
0.8±1.9
0 (0–1)
1.1±2.1
0 (0–1)
0.9±2.0
0 (0–1)
0.6±1.5
0 (0–1)
1.0±2.6
0 (0–1)
0.8±2.3
0 (0–1)
 No of emergency room visits,
 Median (IQR)
0.6±2.9
0 (0–0)
0.7±3.1
0 (0–0)
0.6±3.0
0 (0–0)
0.5±2.6
0 (0–0)
0.7±3.0
0 (0–0)
0.5±2.6
0 (0–0)
 No of prescription drugs,
 Median (IQR)
9.8±6.6
9 (5–13)
9.3±6.4
8 (5–12)
8.5±6.0
7 (4–11)
10.6±6.6
9 (6–14)
11.2±7.3
10 (6–15)
7.8±5.6
7 (4–11)
 Acute hospitalizations162410142315
Preventive medical services
 Pap smears445045404441
 HPV DNA tests788586
 Mammograms434242444041
 Fecal occult blood tests121312121111
 Serum cholesterol tests413943414259
 Sigmoidoscopy/colonoscopy16517897
  • *SID and non-SID cohorts are age- and index date-matched.

  • †The range of combined comorbidity score is −2 to 26.

  • ‡Systemic immunosuppressive drugs include azathioprine, cyclophosphamide, ciclosporin, hydroxyurea, leflunomide, methotrexate, 6-mercaptopurine, mycophenolate, pimecrolimus, tacrolimus, abatacept, adalimumab, alefacept, anakinra, certolizumab pegol, etanercept, golimumab, infliximab, rituximab, tocilizumab and ustekinumab.

  • §Cumulative steroid dose equivalent to prednisone was calculated over the 365-day baseline period.

  • HPV, human papillomavirus; NSAIDs, non-steroidal anti-inflammatory drugs; Pap, Papanicolaou; SID, systemic inflammatory disease.