TABLE 1.
Characteristics of Cases and Matched Controls
| Covariates | Cases n = 51,029 | Controls n = 188,391 | |
|---|---|---|---|
| DxCG risk score, median; mean [± SD] | 1.3; 1.6 [± 1.8] | 0.8; 0.9 [± 1.2] | |
| Concomitant medical conditions, n (%) | |||
| Previous pneumonia | 3,132 (6.1) | 2,148 (1.1) | |
| Asthma | 10,807 (21.2) | 18,261 (9.7) | |
| Chronic obstructive pulmonary disease | 19,810 (38.8) | 28,626 (15.2) | |
| Upper respiratory tract infection | 10,210 (20.0) | 27,444 (14.6) | |
| Smoking | 12,143 (23.8) | 30,571 (16.2) | |
| Alcohol | 881 (1.7) | 2,053 (1.1) | |
| Acute myocardial infarction | 2,860 (5.6) | 3,658 (1.9) | |
| Dementia | 3,150 (6.2) | 7,413 (3.9) | |
| Swallowing disorders | 3,316 (6.5) | 6,300 (3.3) | |
| Nausea | 5,837 (11.4) | 11,111 (5.9) | |
| Parkinson’s disease | 1,117 (2.2) | 2,795 (1.5) | |
| Concomitant medications, n (%) | |||
| Anticonvulsants | 4,433 (8.7) | 9,030 (4.8) | |
| Antidepressants | 15,238 (29.9) | 35,710 (19.0) | |
| Antipsychotics | 2,955 (5.8) | 4,892 (2.6) | |
| Benzodiazepines | 10,200 (20.0) | 23,778 (12.6) | |
| Mood stabilizers | 450 (0.9) | 861 (0.5) | |
| Opioids | 21,857 (42.8) | 53,336 (28.3) | |
| Proton pump inhibitors | 13,751 (27.0) | 32,412 (17.2) | |
| H2 receptor antagonists | 7887 (15.5) | 21,411 (11.4) | |
Note: Differences between cases and controls for covariates above had P values < 0.05.
DxCG = Diagnostic Cost Groups comorbidity score; SD = standard deviation.