Table 1.
Baseline characteristics
| Patients (n=989 800) | ||
|---|---|---|
| Length of CPRD follow-up in years | 5·2 (2·3–9·0) | |
| Mean age, years | 71·7 (7·9) | |
| Median age, years | 68·6 (65·0–77·0) | |
| Age groups, years | ||
| 65–69 | 528 580 (53·4%) | |
| 70–74 | 153 969 (15·6%) | |
| 75–79 | 124 514 (12·6%) | |
| 80–84 | 97 505 (9·9%) | |
| 85–89 | 50 785 (5·1%) | |
| ≥90 | 34 447 (3·5%) | |
| Sex | ||
| Male | 452 198 (45·7%) | |
| Female | 537 602 (54·3%) | |
| Ethnicity | ||
| White | 865 338 (87·4%) | |
| South Asian | 16 901 (1·7%) | |
| Black | 8749 (0·9%) | |
| Mixed/Other | 9938 (1·0%) | |
| Missing | 88 874 (9·0%) | |
| Patient-level Index of Multiple Deprivation | ||
| 1 (least deprived) | 238 449 (24·1%) | |
| 2 | 233 517 (23·6%) | |
| 3 | 213 430 (21·6%) | |
| 4 | 172 086 (17·4%) | |
| 5 (most deprived) | 132 318 (13·4%) | |
| Body-mass index | ||
| Underweight (<18·5) | 17 480 (1·8%) | |
| Normal weight (18·5–24·9) | 313 044 (31·6%) | |
| Overweight (25·0–29·9) | 356 014 (36·0%) | |
| Obese or morbidly obese (≥30·0) | 210 051 (21·2%) | |
| Missing | 93 211 (9·4%) | |
| Smoking status | ||
| Never-smoked | 441 851 (44·6%) | |
| Current smoker | 149 104 (15·1%) | |
| Former smoker | 374 654 (37·9%) | |
| Missing | 24 191 (2·4%) | |
| Heavy alcohol consumption | 54 663 (5·5%) | |
| Comorbidities | ||
| Depression or anxiety | 109 672 (11·1%) | |
| Severe mental illness | 7659 (0·8%) | |
| Inflammatory bowel disease | 31 971 (3·2%) | |
| Multiple sclerosis | 3168 (0·3%) | |
| Rheumatoid arthritis | 20 486 (2·1%) | |
| Psoriasis | 37 872 (3·8%) | |
| Asthma | 120 429 (12·2%) | |
| Chronic kidney disease | 40 220 (4·1%) | |
| Chronic liver disease | 18 609 (1·9%) | |
| Chronic obstructive pulmonary disease | 109 199 (11·0%) | |
| Diabetes | 118 148 (11·9%) | |
| Heart failure | 50 976 (5·2%) | |
| Hypertension | 424 439 (42·9%) | |
| Myocardial infarction | 55 590 (5·6%) | |
| Obstructive sleep apnoea | 7278 (0·7%) | |
| Stroke | 44 430 (4·5%) | |
| Traumatic brain injury | 10 692 (1·1%) | |
| Medication use | ||
| Benzodiazepines | 42 066 (4·2%) | |
| Proton pump inhibitors | 191 895 (19·4%) | |
| Systemic corticosteroids | 85 594 (8·6%) | |
| Polypharmacy | 296 201 (29·9%) | |
Data are n (%), mean (SD), or median (IQR). Comorbidities were assessed at any time before the start of follow-up. Medication use was captured in the 12 months prior to baseline. Polypharmacy as the concurrent use of five or more medications using British National Formulary chapters. CPRD=clinical practice research datalink.