Risk of Malignant Neoplasm in Patients with Incident Rheumatoid Arthritis 1980–2007 in relation to a Comparator Cohort: A Population-Based Study
Table 2
Risk factors for malignancy in 813 patients with rheumatoid arthritis (RA) at RA incidence and during follow-up.
Characteristic
Value
Hazard ratio for any malignancy (95% CI)
Hazard ratio for hematologic malignancy (95% CI)
Hazard ratio for lung cancer (95% CI)
Baseline characteristics
Age, mean (± SD)
55.9 (± 15.7)
1.64 (1.44, 1.86)
1.98 (1.44, 2.71)
1.91 (1.41, 2.59)
Female sex
556 (68.4%)
0.70 (0.50, 0.99)
0.89 (0.39, 2.01)
0.61 (0.28, 1.30)
Calendar year of RA incidence, mean (± SD)
1995.6 (± 7.9)
1.06 (0.83, 1.35)
1.64 (0.86, 3.12)
1.06 (0.60, 1.88)
ESR at index, mean (± SD)
24.8 (± 20.5)
0.99 (0.90, 1.09)
0.89 (0.70, 1.13)
1.05 (0.87, 1.27)
Highest ESR in 1st year, mean (± SD)
32.7 (± 25.7)
1.00 (0.92, 1.08)
0.93 (0.77, 1.13)
1.03 (0.88, 1.21)
Rheumatoid factor positive
539 (66%)
0.91 (0.64, 1.30)
0.79 (0.35, 1.77)
3.59 (1.23, 10.48)
Current smoker
178 (22%)
1.60 (1.09, 2.34)
0.38 (0.09, 1.63)
22.40 (8.48, 59.21)
Former smoker
271 (33%)
0.91 (0.63, 1.31)
1.60 (0.72, 3.56)
0.42 (0.17, 1.06)
Body mass index, kg/m2
27.7 (± 5.9)
1.00 (0.97, 1.03)
0.95 (0.88, 1.04)
0.95 (0.87, 1.03)
Obesity (body mass index ≥ 30 kg/m2)
244 (30.0%)
0.75 (0.50, 1.13)
0.81 (0.32, 2.05)
0.77 (0.31, 1.92)
Time-dependent characteristics
BMI ≥ 30 kg/m2, ever
391 (48%)
1.03 (0.73, 1.45)
0.89 (0.40, 1.98)
0.61 (0.27, 1.36)
BMI < 20 kg/m2, ever
196 (24%)
0.83 (0.51, 1.34)
0.66 (0.19, 2.28)
3.12 (1.29, 7.55)
Alcohol abuse
69 (8%)
1.82 (1.07, 3.10)
—
7.89 (3.41, 18.22)
Rheumatoid nodules
272 (33%)
1.20 (0.83, 1.73)
1.95 (0.87, 4.37)
2.49 (1.14, 5.40)
Erosions/destructive changes
459 (56%)
1.47 (1.04, 2.09)
1.88 (0.81, 4.34)
2.65 (1.14, 6.16)
Severe extra-articular manifestation of RA
94 (12%)
1.41 (0.84, 2.35)
0.79 (0.19, 3.38)
1.99 (0.75, 5.29)
Large joint swelling
648 (80%)
1.06 (0.70, 1.60)
0.85 (0.33, 2.17)
3.42 (0.81, 14.54)
Joint synovectomy
89 (11%)
1.53 (0.93, 2.52)
0.69 (0.16, 2.98)
1.06 (0.31, 3.61)
Joint arthroplasty
174 (21%)
0.96 (0.61, 1.49)
0.27 (0.06, 1.18)
1.21 (0.50, 2.96)
Ever 3 ESR ≥ 60 mm/1 hr
114 (14%)
1.29 (0.78, 2.14)
0.62 (0.15, 2.67)
0.55 (0.13, 2.33)
Methotrexate
495 (61%)
1.04 (0.72, 1.50)
0.74 (0.31, 1.73)
1.49 (0.66, 3.39)
Other DMARD
580 (71%)
1.29 (0.88, 1.90)
1.35 (0.55, 3.31)
2.38 (0.91, 6.22)
Biologics
175 (22%)
0.69 (0.36, 1.35)
1.16 (0.32, 4.14)
0.34 (0.04, 2.61)
Glucocorticoids
650 (80%)
1.57 (1.04, 2.39)
0.87 (0.34, 2.22)
1.39 (0.54, 3.62)
COX-2 inhibitor
393 (48%)
1.09 (0.74, 1.60)
1.52 (0.65, 3.55)
1.10 (0.47, 2.58)
ASA (≥1950 mg/day; ≥3 mo)
338 (42%)
0.76 (0.51, 1.13)
0.53 (0.21, 1.34)
0.63 (0.26, 1.52)
NSAIDs for RA
738 (91%)
0.67 (0.40, 1.10)
1.17 (0.27, 5.04)
0.48 (0.18, 1.29)
Values are (%) unless otherwise specified. Adjusted for age, sex, and calendar year of RA incidence. Hazard ratio reported per 10 units increase. ASA = acetylated salicylate; BMI = body mass index; CI = confidence interval; ESR = erythrocyte sedimentation rate; COX2 = cyclooxygenase 2; DMARD = disease modifying antirheumatic drugs; NSAID = nonsteroidal anti-inflammatory drug; RA = rheumatoid arthritis.
