Smokers, n (%) | Non-smokers, n (%) | OR (95% CI) | P value | |
Age at last follow-up, mean (SD) | 55 (15) | 50 (17) | 0.000025 | |
Disease duration, mean (SD) | 17 (11) | 16 (12) | 0.016 | |
Male sex | 49 (13) | 48 (13) | 0.94 (0.61 to 1.45) | 0.79 |
Deceased at follow-up | 55 (15) | 39 (11) | 1.19 (0.75 to 1.88) | 0.45 |
ACR 1982 classification criteria40 | ||||
1 Malar rash | 205 (55) | 211 (57) | 1.00 (0.74 to 1.34) | 0.97 |
2 Discoid rash | 83 (22) | 80 (21) | 0.96 (0.68 to 1.36) | 0.81 |
3 Photosensitivity | 262 (71) | 246 (65) | 1.27 (0.93 to 1.74) | 0.13 |
4 Oral ulcer | 103 (28) | 96 (25) | 1.20 (0.86 to 1.67) | 0.27 |
5 Arthritis | 306 (82) | 301 (81) | 1.11 (0.76 to 1.61) | 0.59 |
6 Serositis | 179 (48) | 165 (45) | 1.10 (0.82 to 1.47) | 0.52 |
7 Renal disorder | 129 (35) | 132 (36) | 1.10 (0.80 to 1.50) | 0.56 |
8 Neurological disorder | 33 (9) | 40 (10) | 0.86 (0.52 to 1.40) | 0.54 |
9 Haematological disorder | 213 (57) | 258 (70) | 0.62 (0.46 to 0.84) | 0.0021 |
10 Immunological disorder | 245 (66) | 256 (69) | 0.97 (0.71 to 1.33) | 0.86 |
Anti-dsDNA | 224 (61) | 231 (63) | 1.02 (0.76 to 1.38) | 0.88 |
11 ANA | 364 (98) | 367 (99) | 0.69 (0.19 to 2.49) | 0.57 |
Renal variables | ||||
WHO class I–II | 12 (5) | 20 (8) | 0.71 (0.33 to 1.50) | 0.37 |
WHO class III–IV | 62 (21) | 71 (22) | 1.13 (0.75 to 1.69) | 0.57 |
WHO class V | 15 (6) | 16 (6) | 1.05 (0.50 to 2.20) | 0.90 |
Other* | 11 (4) | 6 (2) | 1.24 (0.50 to 3.06) | 0.65 |
ESRD | 14 (4) | 1.41 (0.62 to 3.24) | 0.42 | |
Cardiovascular events | ||||
MI | 39 (11) | 19 (5) | 1.96 (1.09 to 3.55) | 0.025 |
ICVD | 45 (12) | 30 (8) | 1.37 (0.84 to 2.24) | 0.21 |
VTE | 61 (16) | 52 (14) | 1.14 (0.76 to 1.71) | 0.52 |
Clinical APS | 68 (20) | 61 (18) | 1.08 (0.73 to 1.60) | 0.68 |
Anti-β2GP-I IgG | 58 (19) | 57 (18) | 0.98 (0.69 to 1.39) | 0.91 |
Anti-β2GP-I IgM | 8 (11) | 11 (12) | 0.96 (0.36 to 2.55) | 0.93 |
LA | 62 (23) | 57 (21) | 1.19 (0.79 to 1.80) | 0.40 |
aCL-IgG | 86 (26) | 90 (28) | 1.05 (0.70 to 1.59) | 0.080 |
aCL-IgM | 34 (14) | 33 (13) | 0.96 (0.36 to 2.55) | 0.93 |
Logistic regression models were used to assess differences between smokers and non-smokers. All analyses were adjusted for age at last follow-up and disease duration.
p<0.05 (unadjusted for multiple comparisons) in bold.
*Patients with biopsies displaying signs of nephritis but not meeting the criteria for any of the above classes were classified as other.
ACR, American College of Rheumatology;40 ANA, antinuclear antibodies; Anti-β2GP-I, anti-β2 Glycoprotein-I; ; APS, antiphospholipid syndrome; dsDNA, double-stranded DNA; ESRD, end-stage renal disease; ICVD, ischaemic cerebrovascular disease; LA, lupus anticoagulant; MI, myocardial infarction; VTE, venous thromboembolism.;