Table 2.
Participant demographic and clinical characteristics at the index date
| FEP patients (n = 3045) | Matched participants (n = 12,180) | p value | |
|---|---|---|---|
| Type of psychosis, n (%) | |||
| Non-affective | 2036 (66.9) | NA | |
| Drug-induced | 678 (22.3) | NA | |
| Affective | 309 (10.2) | NA | |
| Pregnancy-related | 22 (0.7) | NA | |
| Year of the index date, median (IQR) | 2010 (2007, 2013) | 2010 (2007, 2013) | Matched |
| Age, median (IQR) | 30 (23, 39) | 30 (23, 39) | Matched |
| Male, n (%) | 1914 (62.9) | 7656 (62.9) | Matched |
| Geographical region, n (%) | Matched | ||
| London | 271 (8.9) | 1084 (8.9) | |
| South England | 798 (26.2) | 3192 (26.2) | |
| Midlands and East England | 599 (19.7) | 2396 (19.7) | |
| North England | 532 (17.5) | 2128 (17.5) | |
| Northern Ireland | 168 (5.5) | 672 (5.5) | |
| Scotland | 356 (11.7) | 1424 (11.7) | |
| Wales | 321 (10.5) | 1284 (10.5) | |
| Smoking, n (%) | < 0.0001 | ||
| Non-smoker | 1011 (33.2) | 6041 (49.6) | |
| Ever smoker | 1764 (57.9) | 4031 (33.1) | |
| Unknown | 270 (8.9) | 2108 (17.3) | |
| Alcohol consumption, n (%) | NS | ||
| Non-drinker | 298 (9.8) | 1026 (8.4) | |
| Ever drinker | 1742 (57.2) | 5907 (48.5) | |
| Unknown | 1005 (33.0) | 5247 (43.1) | |
| Body mass index, median (IQR) | 23.8 (21.0, 27.9) | 24.5 (21.6, 28.3) | < 0.0001 |
| < 18.5 kg/m2 (underweight), n (%) | 150 (4.9) | 326 (2.7) | |
| ≥ 18.5 kg/m2 and < 25 kg/m2 (normal), n (%) | 1085 (35.6) | 3578 (29.4) | |
| ≥ 25 kg/m2 and < 30 kg/m2 (overweight), n (%) | 501 (16.5) | 2025 (16.6) | |
| ≥ 30 kg/m2 (obese), n (%) | 355 (11.7) | 1355 (11.1) | |
| Unknown, n (%) | 954 (31.3) | 4896 (40.2) | |
| Number of different prescriptions in 5 years before the index date, median (IQR) | 4 (3, 6) | 3 (1, 5) | < 0.0001 |
| Number of GP consultations in 5 years before the index date, median (IQR) | 55 (29, 95) | 25 (10, 53) | < 0.0001 |
| 4–5 years prior to the index date | 6 (2, 15)† | 3 (1, 9) | < 0.0001 |
| 3–4 years prior to the index date | 7 (2, 16)† | 4 (1, 10) | < 0.0001 |
| 2–3 years prior to the index date | 8 (2, 18)† | 4 (1, 11) | < 0.0001 |
| 1–2 years prior to the index date | 9 (3, 20)† | 4 (1, 11) | < 0.0001 |
| 0–1 year prior to the index date | 17 (8, 30)† | 4 (1, 12) | < 0.0001 |
| Number of symptom records in 5 years before the index date, median (IQR)‡ | 2 (1, 5) | 0 (0, 1) | < 0.0001 |
p value obtained from chi-squared or from Mann-Whitney U test as appropriate, and where applicable analysis excluded the ‘unknown’ category (missing data)
FEP first episode psychosis, IQR interquartile range, NA not applicable, NS not significant
†One-way ANOVA trend analysis within patients with FEP, p < 0.0001
‡Total number of coded records based on 55 studied individual symptoms