Baseline characteristics
| Clozapine (n=100) | Non-clozapine (n=21) | Controls (n=20) | p Value | |
|---|---|---|---|---|
| Age (years) | 40±12 | 37±14 | 43±13 | 0.33 |
| Gender | ||||
| Male | 54 (54) | 15 (72) | 13 (65) | 0.28 |
| Schizophrenia | ||||
| Duration of illness (years) | 16.5±9.7 | 11.8±8.0 | – | |
| Family history of mental illness | 11 (11) | 5 (24) | 0 | 0.06 |
| Antipsychotic treatment | ||||
| Duration of treatment (years) | 6.8±5.3 | 9.7±6.1 | ||
| Dosage at time of study (mg/day) | 372±155 | – | ||
| Body mass index (kg/m2) | 29.6±7.0 | 29.4±7.4 | 23.5±2.5 | 0.02*†‡ |
| Comorbidities | ||||
| Alcohol excess | 9 (9) | 2 (10) | 0 | 0.38 |
| Heart failure | ||||
| Previous history of heart failure | 0 | 1 (5) | 0 | 0.06 |
| NYHA Class >1 | 0 | 1 (5) | 0 | 0.06 |
| Stroke | 1 (1) | 0 | 0 | 0.82 |
| Risk factors for IHD | ||||
| Diabetes | 23 (23) | 5 (24) | 2 (10) | 0.42 |
| Family history of IHD | 24 (24) | 3 (14) | 2 (10) | 0.28 |
| Hypercholesterolaemia | 30 (30) | 6 (29) | 0 | 0.02*† |
| Statin therapy | 18(18) | 4(19) | 0 | 0.12 |
| Hypertension | 9 (9) | 5 (24) | 4 (20) | 0.11 |
| Smoking | 57 (57) | 10 (53) | 2 (10) | <0.001*† |
| Cardiac observations | ||||
| Systolic blood pressure (mm Hg) | 119±13 | 124±11 | 119±11 | 0.28 |
| Diastolic blood pressure (mm Hg) | 76±8 | 76±8 | 73±8 | 0.22 |
| Resting heart rate (bpm) | 93±12 | 79±11 | 70±7 | <0.001*† |
| QTc (ms) | 417±23 | 394±22 | 402±26 | <0.001* |
Values are presented as mean±SD or absolute number (%).
*p<0.05 (ANOVA).
†Post hoc Tukey analysis between clozapine and healthy controls, p value <0.05.
‡Post hoc Tukey analysis between non-clozapine and healthy controls, p value <0.05.
ANOVA, analysis of variance; IHD, ischaemic heart disease; NYHA, the New York Heart Association; QTc, corrected QT interval.