Table 3. Propensity Score–Matched Univariate Logistic Regression, 1:2 Case-Control Matching.
| Characteristic | Overall, No. (%) (n = 105) | BP status, No. (%) | Odds ratio (95% CI) | P value | |
|---|---|---|---|---|---|
| No BP (n = 70) | BP (n = 35) | ||||
| Sex | |||||
| Male | 67 (63.8) | 42 (60.0) | 25 (71.4) | 1 [Reference] | .25 |
| Female | 38 (36.2) | 28 (40.0) | 10 (28.6) | 0.60 (0.24-1.41) | |
| Race and ethnicity | |||||
| White | 101 (96.2) | 68 (97.1) | 33 (94.3) | 1 [Reference] | .48 |
| Othera | 4 (3.8) | 2 (2.9) | 2 (5.7) | 2.06 (0.24-17.80) | |
| Cancer stage | |||||
| Non–stage IV | 25 (23.8) | 19 (27.1) | 6 (17.1) | 1 [Reference] | .26 |
| Stage IV | 80 (76.2) | 51 (72.9) | 29 (82.9) | 1.80 (0.67-5.40) | |
| Cancer status at time of first ICI cycle | |||||
| No distant metastases | 23 (21.9) | 15 (21.4) | 8 (22.9) | 1 [Reference] | .87 |
| Distant metastases | 82 (78.1) | 55 (78.6) | 27 (77.1) | 0.92 (0.35-2.53) | |
| Site of distant metastases | |||||
| Brain | |||||
| No | 91 (86.7) | 59 (84.3) | 32 (91.4) | 1 [Reference] | .29 |
| Yes | 14 (13.3) | 11 (15.7) | 3 (8.6) | 0.50 (0.11-1.75) | |
| Skin | |||||
| No | 95 (90.5) | 64 (91.4) | 31 (88.6) | 1 [Reference] | .64 |
| Yes | 10 (9.5) | 6 (8.6) | 4 (11.4) | 1.38 (0.33-5.17) | |
| Medical history | |||||
| Type 2 diabetes | |||||
| No | 80 (76.2) | 53 (75.7) | 27 (77.1) | 1 [Reference] | .87 |
| Yes | 25 (23.8) | 17 (24.3) | 8 (22.9) | 0.92 (0.34-2.36) | |
| Cerebrovascular disease | |||||
| No | 92 (87.6) | 61 (87.1) | 31 (88.6) | 1 [Reference] | .83 |
| Yes | 13 (12.4) | 9 (12.9) | 4 (11.4) | 0.87 (0.22-2.92) | |
| Neurocognitive disease | |||||
| No | 102 (97.1) | 68 (97.1) | 34 (97.1) | 1 [Reference] | .99 |
| Yes | 3 (2.9) | 2 (2.9) | 1 (2.9) | 1 (0.05-10.80) | |
| Autoimmune disease | |||||
| No | 95 (90.5) | 63 (90.0) | 32 (91.4) | 1 [Reference] | .81 |
| Yesb,c | 10 (9.5) | 7 (10.0) | 3 (8.6) | 0.84 (0.17-3.26) | |
| Vaccination within 6 mo before ICI | |||||
| No | 87 (82.9) | 58 (82.9) | 29 (82.9) | 1 [Reference] | .99 |
| Yes | 18 (17.1) | 12 (17.1) | 6 (17.1) | 1 (0.32-2.86) | |
| Radiation before ICI | |||||
| No | 68 (64.8) | 47 (67.1) | 21 (60.0) | 1 [Reference] | .47 |
| Yes | 37 (35.2) | 23 (32.9) | 14 (40.0) | 1.36 (0.58-3.15) | |
| Initial tumor response to ICI | |||||
| Stable disease or progression of disease | 39 (37.1) | 32 (45.7) | 7 (20.0) | 1 [Reference] | .01 |
| Complete or partial response | 66 (62.9) | 38 (54.3) | 28 (80.0) | 3.37 (1.35-9.30) | |
| BMI >25 | |||||
| ≤25 | 40 (38.1) | 27 (38.6) | 13 (37.1) | 1 [Reference] | .89 |
| >25 | 65 (61.9) | 43 (61.4) | 22 (62.9) | 1.06 (0.46-2.49) | |
| BMI >30 | |||||
| ≤30 | 82 (78.1) | 55 (78.6) | 27 (77.1) | 1 [Reference] | .87 |
| >30 | 23 (21.9) | 15 (21.4) | 8 (22.9) | 1.09 (0.40-2.83) | |
| dNLRd | |||||
| ≤3.0 | 78 (74.3) | 55 (78.6) | 23 (65.7) | 1 [Reference] | .16 |
| >3.0 | 27 (25.7) | 15 (21.4) | 12 (34.3) | 1.91 (0.77-4.73) | |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); BP, bullous pemphigoid; dNLR, derived neutrophil-to-lymphocyte ratio; ICI, immune checkpoint inhibitor.
In the no BP group (70), other race and ethnicity included Asian and Pacific Islander (1 [1.4%]) individuals and those with unspecified race and ethnicity (1 [1.4%]). In the BP group (35), other race and ethnicity included Asian and Pacific Islander individuals (1 [2.9%]) and Hispanic or Latino individuals (1 [2.9%]).
Autoimmune diseases among the patients who developed BP (35) included Hashimoto disease (3 [8.6%]).
Autoimmune diseases among the patients in the no BP group (70) included Crohn disease (2 [2.9%]), immune thrombocytopenic purpura (1 [1.4%]), multiple sclerosis (1 [1.4%]), psoriasis (1 [1.4%]), psoriatic arthritis (1 [1.4%]), and rheumatoid arthritis (1 [1.4%]).
The dNLR was calculated as dNLR = (absolute neutrophil count)/(white blood cell count − absolute neutrophil count). For each patient, blood cell counts used in the dNLR formula were taken from the same complete blood count on the day of receiving the first ICI cycle.