Table 1.
Descriptive statistics of all clozapine discontinuers, and those who re-started versus those who did not re-start clozapine during follow-up
| All clozapine discontinuers, N = 2250 | Those who did not re-start clozapine during the follow-up, n = 1871 | Those who re-started clozapine during the follow-up but ≥1 year after clozapine cessation, n = 379 | P-valuea | |
|---|---|---|---|---|
| Male gender, percentage (number) | 57.2 (1287) | 56.4 (1056) | 61.0 (231) | 0.1057 |
| Median age at schizophrenia diagnoses (IQR), years | 27 (22–35) | 28 (23–36) | 25 (22–31) | <0.0001 |
| Median age at clozapine discontinuation (IQR), years | 46 (34–58) | 48 (36–59) | 38 (30–48) | <0.0001 |
| Median duration of clozapine use before discontinuation (IQR), years | 4.1 (2.0–8.0) | 4.5 (2.2–8.5) | 2.9 (1.7–5.8) | <0.0001 |
| Median time to clozapine reinitiation (IQR), years | 2.1 (1.4–4.3) | |||
| Most frequently initiated first antipsychotics during the first year after clozapine discontinuationb | ||||
| Antipsychotic polypharmacy | 26.5 (409) | 27.0 (350) | 24.0 (59) | 0.3313 |
| Olanzapine | 22.3 (344) | 23.2 (301) | 17.5 (43) | 0.0485 |
| Quetiapine | 13.6 (210) | 13.0 (169) | 16.7 (41) | 0.1261 |
| Aripiprazole | 12.1 (186) | 12.1 (157) | 11.8 (29) | 0.8921 |
| Risperidone | 5.2 (80) | 5.2 (68) | 4.9 (12) | 0.8149 |
| Levomepromazine | 3.4 (52) | 3.3 (43) | 3.7 (9) | 0.7828 |
| Any LAI | 3.9 (60) | 3.6 (47) | 5.3 (13) | 0.2158 |
IQR, interquartile range; LAI, long-acting injectable antipsychotic.
a.
P-value: chi-squared test for categorical variables and Kruskal–Wallis test for continuous variables, comparing those who re-started clozapine with those who did not.
b.
n = 1544 initiated some antipsychotic drug during the first year after clozapine discontinuation (n = 1298 among those who did not re-start clozapine and n = 379 among those who re-started clozapine during follow-up); in these rows, percentages (n) of the types of antipsychotics used by these patient (sub)categories are given.