Table 1.
Characteristics of Incident Pneumonia Case Subjects and Controls Derived From a Nationwide Cohort With Schizophrenia, From 2000 to 2008 (N = 33 024)
| Characteristic N (%) | Case (N = 1739) | Controls (N = 6949) | Unadjusted Risk Ratioa | 95% CI |
| N (%) | N (%) | |||
| At first admission | ||||
| Men | 1088 (62.9) | 4350 (62.9) | — | — |
| Age, mean (SD) (y) | 42.8 (12.6) | 42.7 (12.6) | 1.47** | 1.24–1.75 |
| Charlson comorbidity index | ||||
| 1 | 1361 (78.3) | 5818 (83.7) | Reference | |
| 2 | 286 (16.5) | 946 (13.6) | 1.30** | 1.12–1.50 |
| ≥3 | 92 (5.3) | 185 (2.7) | 2.16** | 1.67–2.80 |
| Within 180 d before the index date | ||||
| Number of psychiatric hospital admissions, mean (SD) | 0.7 (0.9) | 0.4 (0.6) | 1.95** | 1.80–2.11 |
| Physical illnesses | ||||
| Cardiovascular disease | 574 (33.0) | 1308 (18.8) | 2.32** | 2.05–2.63 |
| Diabetes mellitus | 262 (15.1) | 595 (8.6) | 1.95** | 1.66–2.28 |
| Cerebrovascular disease | 110 (6.3) | 92 (1.3) | 5.33** | 3.98–7.15 |
| Chronic hepatic disease | 177 (10.2) | 360 (5.2) | 2.09** | 1.73–2.53 |
| Cancer | 91 (5.2) | 76 (1.1) | 5.12** | 3.74–7.03 |
| Asthma | 115 (6.6) | 117 (1.7) | 4.17** | 3.20–5.44 |
| Upper respiratory tract infection | 722 (41.5) | 2134 (30.7) | 1.62** | 1.45–1.81 |
| Deliriumb | 24 (1.38) | 27 (0.39) | 3.62** | 2.08–6.32 |
| Concomitant drugs | ||||
| Cardiovascular drugs | ||||
| Antihypertensive agents | 104 (6.0) | 165 (2.4) | 2.67** | 2.07–3.44 |
| Beta blocking agents | 707 (40.7) | 2126 (30.6) | 1.57** | 1.40–1.75 |
| Calcium channel blockers | 341 (19.6) | 662 (9.5) | 2.46** | 2.12–2.86 |
| Agents acting on the renin-angiotensin system | 184 (10.6) | 393 (5.7) | 2.06** | 1.70–2.49 |
| Lipid modifying agents | 81 (4.7) | 261 (3.8) | 1.26 | 0.97–1.62 |
| Respiratory drugsc | 1606 (92.4) | 3548 (51.1) | 11.60** | 9.63–13.98 |
| Drugs used in diabetes | 278 (16.0) | 527 (7.6) | 2.40** | 2.05–2.82 |
| Antithrombotic agents | 238 (13.7) | 372 (5.4) | 2.98** | 2.49–3.57 |
| Corticosteroids for systemic use | 541 (31.1) | 670 (9.6) | 4.30** | 3.77–4.92 |
| Anti-Parkinson drugs | 1265 (72.7) | 4484 (64.5) | 1.49** | 1.32–1.67 |
a
Estimated using univariate conditional logistic regression, **P < .001.
b
Based on ICD-9 code, including presenile dementia with delirium, senile dementia with delirium, arteriosclerotic dementia with delirium, alcohol withdrawal delirium, drug-induced delirium, acute delirium, subacute delirium.
c
Based on Anatomical Therapeutic Chemical code, including nasal preparations, throat preparations, drugs for obstructive airway diseases, cough and cold preparations, antihistamines for systemic use, other respiratory system products.