Table 3.
Clinical outcome comparison between subjects with low vs normal IgM
| Low IgM (N = 16) | Normal IgM (N = 34) | p | |
|---|---|---|---|
| Demographics | |||
| Age years (median {IQR}) | 70.5 (65.5–73.0) | 65 (58–79) | 0.235 |
| Sex—female (n {%}) | 7(43.8%) | 20(58.8%) | 0.373 |
| BMI* (kg/m2) (median {IQR}) | 25.6 (22.6–33.5) | 26.4 (19.4–31.9) | 0.456 |
| FEV1** (% predicted) (median. {IQR}) | 43.9 (21.6–68.1) | 35.1 (24.5–44.4) | 0.270 |
| FEV1/FVC** (%) (median {IQR}) | 46.7 (38.8–52.2) | 41.1 (32.7–52.3) | 0.292 |
| Current Smoking* (n {%}) | 6/16 (37.5%) | 6/33 (18.2%) | 0.169 |
| Number of pack years***(median {IQR}) | 50.0 (35.1–58.5) | 40.0 (20.2–50.0) | 0.069 |
| Subjects taking systemic corticosteroid (%) | 15 (93.8%) | 32 (94.1%) | 1.000 |
| Subjects taking antibiotics (%) | 15 (93.8%) | 30 (88.2%) | 1.000 |
| Immunoglobulin | |||
| IgG (median {IQR}) | 8.15 (6.00–10.63) | 8.15 (6.99–10.06) | 0.519 |
| IgA (median {IQR}) | 1.84 (1.32–3.40) | 2.04 (1.53–2.65) | 0.685 |
| IgM (median {IQR}) | 0.41 (0.37–0.48) | 1.10 (0.85–1.44) | < 0.0001 |
| Clinical outcome | |||
| Length of hospital stay (median {IQR}) | 6.00 (4.00–8.75) | 3.00 (2.00–5.00) | 0.003 |
| Emergency department visit number (median {IQR}) | 1.00 (0.00–3.75) | 1.50 (0.00–4.00) | 0.633 |
| Readmission (median {IQR}) | 0.50 (0.00–2.00) | 1.00 (0.00–3.00) | 0.597 |
| AECOPD related hospital readmission (median {IQR}) | 0.50 (0.00–1.75) | 0.00 (0.00–2.00) | 0.927 |
Bold values denote statistical significance at the p < 0.05 level
AECOPD Acute chronic obstructive pulmonary disease exacerbation, BMI body mass index, FEV1 forced expiratory volume in 1s, FVC forced vital capacity, Ig immunoglobulin, y year
*n = 16 vs 33 for Low IgM vs Normal IgM
**n = 10 vs 18 for Low IgM vs Normal IgM because of missing data points