Table 2.
Likelihood of receiving a prolactin test: proportional hazards regression results
| Hazard ratio | 95% CI | p Value | |
| Antipsychotic categories vs other typicals (excluded category): | |||
| Risperidone (yes = 1) | 1.341 | 1.085 to 1.658 | 0.0067 |
| Clozapine (yes = 1) | 0.748 | 0.411 to 1.362 | 0.3418 |
| Olanzapine (yes = 1) | 0.948 | 0.788 to 1.229 | 0.8894 |
| Quetiapine (yes = 1) | 0.927 | 0.738 to 1.164 | 0.5124 |
| Ziprasidone (yes = 1) | 1.162 | 0.857 to 1.576 | 0.3343 |
| Haloperidol (yes = 1) | 0.852 | 0.609 to 1.319 | 0.3523 |
| Perphenazine (yes = 1) | 0.741 | 0.416 to 1.319 | 0.3077 |
| Prolactin-related symptoms prior to event or censoring (yes = 1)* | 6.736 | 5.080 to 8.932 | < 0.0001 |
| Interaction of antipsychotic and PPAE: | |||
| Risperidone × PPAEs | 1.406 | 1.040 to 1.901 | 0.0269 |
| Clozapine × PPAEs | 1.340 | 0.617 to 2.911 | 0.4594 |
| Olanzapine × PPAEs | 1.156 | 0.838 to 1.593 | 0.3771 |
| Quetiapine × PPAEs | 0.936 | 0.673 to 1.302 | 0.6929 |
| Ziprasidone × PPAEs | 1.068 | 0.686 to 1.663 | 0.7710 |
| Haloperidol × PPAEs | 1.094 | 0.676 to 1.770 | 0.7134 |
| Perphenazine × PPAEs | 1.608 | 0.747 to 3.463 | 0.3077 |
| Age | 0.962 | 0.959 to 0.964 | < 0.0001 |
| Male gender | 0.329 | 0.300 to 0.361 | < 0.0001 |
| Used another antipsychotic within 6 months prior to treatment (yes = 1) | 1.070 | 0.984 to 1.164 | 0.1130 |
| Concurrent use of other atypical antipsychotic, ratio of days supply to index antipsychotic days supply | 1.647 | 1.465 to 1.852 | < 0.0001 |
| Concurrent use of other typical antipsychotic, ratio of days supply to index antipsychotic days supply | 1.136 | 0.954 to 1.354 | 0.1531 |
| Diagnosis: | |||
| Schizophrenia (yes = 1) | 1.009 | 0.925 to 1.101 | 0.8352 |
| Affective psychosis (yes = 1) | 1.318 | 1.212 to 1.434 | < 0.0001 |
| Other psychosis (yes = 1) | 0.953 | 0.879 to 1.032 | 0.2370 |
| Other non-psychotic mental disorder (yes = 1) | 1.266 | 1.143 to 1.402 | < 0.0001 |
| Health coverage vs fee-for-service (excluded category): | |||
| Medicaid (yes = 1) | 0.924 | 0.830 to 1.028 | 0.1474 |
| HMO (yes = 1) | 1.146 | 1.016 to 1.293 | 0.0266 |
Number of observations with event: 2,796; number of observations censored: 195,130.
*Gynecomastia, galactorrhea, oligomenorrhea, amenorrhea, dysmenorrhea, hypogonadism, hypothyroidism, infertility-male-hypospermatogenesis, infertility-female-pituitary/hypothalamic, impotence-organic, psychosexual dysfunction, genitourinary malfunctions arising from mental factors, and alopecia.
CI, confidence interval; HMO, health maintenance organization; PPAEs, potentially prolactin-related adverse events.