Table 3.
Demographic and Clinical Characteristics and Diabetes Incidence Among Schizophrenia Patients, by Atypical Antipsychotic Group
| Characteristics | Olanzapine (N = 937) | Risperidone (N = 690) | Clozapine (N = 35) | Quetiapine (N = 164) | P Value | ||||
| Age (mean SD) | 38.4 | 12.4 | 37.2 | 12.3 | 36.8 | 9.5 | 39.7 | 11.1 | 0.0695 |
| Gender (% male) | 469 | 50.1% | 334 | 48.4% | 16 | 45.7% | 58 | 35.4% | 0.0039 |
| Duration of follow-up (mean SD): | 415.4 | 236.8 | 429.4 | 257.3 | 388.9 | 263.0 | 399.8 | 234.3 | 0.1295 |
| Index medication use (mean SD): | |||||||||
| Total duration of therapy | 261.4 | 236.6 | 260.5 | 256.6 | 329.5 | 260.5 | 244.1 | 238.0 | 0.237 |
| Number of prescriptions | 8.3 | 8.4 | 7.5 | 7.0 | 32.0 | 26.8 | 9.0 | 11.1 | < .0001 |
| Year of therapy initiation: | < .0001 | ||||||||
| 1996 | 0 | 0.0% | 9 | 1.3% | 0 | 0.0% | 0 | 0.0% | |
| 1997 | 9 | 1.0% | 6 | 0.9% | 1 | 2.9% | 0 | 0.0% | |
| 1998 | 160 | 17.1% | 101 | 14.6% | 3 | 8.6% | 10 | 6.1% | |
| 1999 | 379 | 40.4% | 243 | 35.2% | 14 | 40.0% | 57 | 34.8% | |
| 2000 | 297 | 31.7% | 266 | 38.6% | 11 | 31.4% | 71 | 43.3% | |
| 2001 | 92 | 9.8% | 65 | 9.4% | 6 | 17.1% | 26 | 15.9% | |
| Plan type: | 0.0001 | ||||||||
| HMO | 449 | 47.9% | 345 | 50.0% | 13 | 37.1% | 72 | 43.9% | |
| PPO | 117 | 12.5% | 99 | 14.3% | 4 | 11.4% | 39 | 23.8% | |
| POS | 104 | 11.1% | 74 | 10.7% | 7 | 20.0% | 16 | 9.8% | |
| Indemnity | 55 | 5.9% | 38 | 5.5% | 7 | 20.0% | 17 | 10.4% | |
| Other | 212 | 22.6% | 134 | 19.4% | 4 | 11.4% | 20 | 12.2% | |
| Geographic region: | < .0001 | ||||||||
| Northeast | 153 | 16.3% | 114 | 16.5% | 4 | 11.4% | 26 | 15.9% | |
| South | 244 | 26.0% | 240 | 34.8% | 5 | 14.3% | 65 | 39.6% | |
| Midwest | 309 | 33.0% | 212 | 30.7% | 20 | 57.1% | 50 | 30.5% | |
| West | 231 | 24.7% | 124 | 18.0% | 6 | 17.1% | 23 | 14.0% | |
| Psychiatric diagnosis: | |||||||||
| Bipolar disorder | 407 | 43.4% | 293 | 42.5% | 7 | 20.0% | 89 | 54.3% | 0.003 |
| Depression | 481 | 51.3% | 375 | 54.3% | 12 | 34.3% | 104 | 63.4% | 0.0071 |
| Medical diagnosis: | |||||||||
| Hypertension | 118 | 12.6% | 81 | 11.7% | 2 | 5.7% | 27 | 16.5% | 0.3264 |
| Cardiovascular disease | 97 | 10.4% | 70 | 10.1% | 2 | 5.7% | 19 | 11.6% | 0.5879 |
| Obesity | 31 | 3.3% | 25 | 3.6% | 2 | 5.7% | 11 | 6.7% | 0.2903 |
| Impaired glucose tolerance | 1 | 0.1% | 0 | 0 | 1 | 2.9% | 0 | 0 | < .0001 |
| Lab tests (mean SD): | |||||||||
| Diabetes screening tests | 1.0 | 2.1 | 0.9 | 1.8 | 0.7 | 1.7 | 1.1 | 1.7 | 0.705 |
| All other general lab tests | 5.4 | 10.0 | 5.8 | 11.6 | 15.7 | 27.5 | 6.2 | 11.4 | < .0001 |
| Incidence of diabetes (%) | 23 | 2.45% | 16 | 2.32% | 2 | 5.71% | 4 | 2.44% | 0.9363 |