Table 4.
Risk factors for time to first infection-related acute care event (hospitalization or emergency department visit) in unadjusted and multivariable adjusted Cox regression analysis among 1741 Cure Glomerulonephropathy Network participants
| Predictors | Infections (n)a | Unadjusted | Multivariable Model (imputed) | ||
|---|---|---|---|---|---|
| IR (95% CI) per 100 person-yra | HR (95% CI) | HR (95% CI) | P Valueb | ||
| Age (yr) | <0.001 | ||||
| ≤10 | 61 | 14.4 (11.2 to 18.5) | 2.69 (1.55 to 4.66) | 4.62 (2.11 to 10.08) | |
| 11–18 | 32 | 6.5 (4.6 to 9.2) | 1.21 (0.67 to 2.21) | 2.22 (1.04 to 4.72) | |
| 19–60 | 54 | 4.7 (3.6 to 6.2) | 0.91 (0.52 to 1.58) | 1.25 (0.68 to 2.27) | |
| >60 | 16 | 5.2 (3.2 to 8.5) | Ref | Ref | |
| Sex | 0.29 | ||||
| Male | 88 | 6.4 (5.2 to 7.9) | 0.85 (0.62 to 1.15) | 0.84 (0.61 to 1.16) | |
| Female | 75 | 7.6 (6.0 to 9.5) | Ref | Ref | |
| Race | 0.22 | ||||
| Black | 35 | 11.1 (7.9 to 15.4) | 1.73 (1.18 to 2.54) | 1.44 (0.95 to 2.17) | |
| Other | 26 | 6.7 (4.5 to 9.8) | 1.07 (0.70 to 1.65) | 1.14 (0.74 to 1.77) | |
| White | 102 | 6.2 (5.1 to 7.5) | Ref | Ref | |
| Glomerular disease type | 0.95 | ||||
| Minimal change disease | 47 | 9.8 (7.3 to 13.0) | 1.77 (1.19 to 2.63) | 0.90 (0.56 to 1.44) | |
| FSGS | 41 | 7.9 (5.8 to 10.7) | 1.41 (0.93 to 2.13) | 0.89 (0.56 to 1.40) | |
| Membranous nephropathy | 25 | 5.6 (3.8 to 8.3) | 1.02 (0.63 to 1.65) | 0.86 (0.49 to 1.50) | |
| IgA nephropathy/vasculitis | 50 | 5.5 (4.1 to 7.2) | Ref | Ref | |
| eGFR at enrollment, per 10 ml/min per 1.73 m2 | — | — | 1.02 (0.97 to 1.07) | 0.96 (0.90 to 10.2) | 0.18 |
| Corticosteroid use at enrollmentc | |||||
| Yes | 83 | 11.1 (9.0 to 13.8) | — | — | |
| No | 80 | 4.9 (4.0 to 6.2) | — | — | |
| Time (≤1 yr)×steroid | 0.16 | ||||
| Yes | 57 | 50.6 (39.1 to 65.6) | 1.81 (1.27 to 2.58) | 1.31 (0.89 to 1.93) | |
| No | 65 | 28.6 (22.4 to 36.5) | Ref | Ref | |
| Time (>1 yr)×steroid | 0.001 | ||||
| Yes | 26 | 4.1 (2.8 to 6.0) | 4.05 (2.14 to 7.67) | 2.99 (1.54 to 5.79) | |
| No | 15 | 1.1 (0.7 to 1.8) | Ref | Ref | |
| Other immunosuppressiond | 0.10 | ||||
| Yes | 77 | 9.8 (7.9 to 12.3) | 1.80 (1.32 to 2.44) | 1.34 (0.94 to 1.91) | |
| No | 86 | 5.4 (4.4 to 6.7) | Ref | Ref | |
| Serum albumin (g/dl)/UPCR (mg/mg) | 0.001 | ||||
| Albumin >2.5 and UPCR >3.5 | 27 | 10.9 (7.5 to 15.9) | 1.88 (1.21 to 2.93) | 1.81 (1.15 to 2.86) | |
| Albumin ≤2.5 and UPCR ≤3.5 | 13 | 13.0 (7.5 to 22.4) | 2.29 (1.27 to 4.14) | 1.83 (1.00 to 3.36) | |
| Albumin ≤2.5 and UPCR >3.5 | 23 | 16.4 (10.9 to 24.7) | 2.82 (1.76 to 4.51) | 2.49 (1.51 to 4.12) | |
| Albumin >2.5 and UPCR ≤3.5 | 72 | 5.6 (4.5 to 7.1) | Ref | Ref | |
| No. of comorbiditiese | — | — | 1.11 (1.00 to 1.22) | 1.22 (1.09 to 1.36) | <0.001 |
| Smoking at enrollment | 0.26 | ||||
| Yes | 36 | 6.1 (4.4 to 8.4) | 0.85 (0.59 to 1.23) | 1.30 (0.82 to 2.06) | |
| No | 127 | 7.2 (6.0 to 8.5) | Ref | Ref | |
| Time from biopsy to enrollment | 0.37 | ||||
| ≤12 mo | 90 | 8.3 (6.7 to 10.2) | 1.39 (1.02 to 1.89) | 1.17 (0.83 to 1.63) | |
| >12 mo | 73 | 5.7 (4.6 to 7.2) | Ref | Ref | |
95% CI, 95% confidence interval; IR, incidence rate; HR, hazard ratio; Ref, reference; UPCR, urinary protein-creatinine ratio.
First infections only.
P values were calculated using joint tests.
Corticosteroid exposure at enrollment (yes/no) violated the proportional hazard assumption (HR, 2.20; 95% CI, 1.62 to 2.99), so a follow-up time interaction model was developed: no exposure (referent) versus exposure and ≤1-yr follow-up versus exposure and >1-yr follow-up.
Other immunosuppressant medications include cyclosporine, oral and intravenous cyclophosphamide, tacrolimus, rituximab, mycophenolate, and azathioprine.
Comorbidities included hypertension, coronary artery disease, aortic aneurysm, valvular heart disease, heart failure, peripheral vascular disease, stroke, asthma, chronic obstructive pulmonary disorder, sickle cell disease, inflammatory bowel disease, cirrhosis, gastrointestinal bleed, HIV, hepatitis B or C, sleep apnea, cancer, or psychiatric diagnosis.