Table 1.
Sample characteristics and predictors of adherence at 1 year.
| Adherence to medication at 12 months of visit | Multivariable analysis | ||||||
|---|---|---|---|---|---|---|---|
| Whole sample | Cluster 1 “Poor adherence” N = 170 (35.1%) | Cluster 2 “Good adherence” N = 315 (64.9%) | Univariate analysis | ||||
| p value | aORa | 95% CI | p value | ||||
| Sociodemographic characteristics | |||||||
| Sex, male, n (%) | 376 (77.5) | 136 (80.0) | 240 (76.2) | 0.338 | |||
| Age, mean (sd) | 32.11 (10.1) | 30.97 (8.8) | 32.73 (10.6) | 0.051 | 0.97 | 0.94–0.99 | 0.043 |
| Diagnosis, schizophrenia (vs schizoaffective disorder) | 367 (75.7) | 125 (73.5) | 242 (76.8) | 0.419 | |||
| Clinical variables | |||||||
| Age at illness onset, mean (sd) | 21.73 (6.7) | 21.34 (6.6) | 21.95 (6.7) | 0.339 | |||
| Illness duration (years), mean (sd) | 10.34 (8.2) | 9.77 (7.2) | 10.65 (8.7) | 0.632 | |||
| PANSS total score, mean (sd) | 69.52 (17.9) | 72.77 (18.6) | 67.71 (17.4) | 0.004 | 1.01 | 0.98–1.02 | |
| PANSS positive score, mean (sd) | 8.25 (3.9) | 8.98 (3.7) | 7.85 (3.9) | <0.001 | 1.07 | 1.00–1.15 | 0.024 |
| PANSS negative score, mean (sd) | 16.06 (6.7) | 16.83 (6.7) | 15.64 (6.7) | 0.044 | 1.02 | 0.97–1.06 | 0.323 |
| PANSS Excitation score, mean (sd) | 5.39 (2.02) | 5.72 (2.2) | 5.21 (1.9) | 0.003 | 0.97 | 0.85–1.11 | 0.474 |
| PANSS Depressive score, mean (sd) | 6.82 (3.0) | 7.65 (3.2) | 6.37 (2.8) | <0.001 | 1.19 | 1.09–1.31 | <0.001 |
| PANSS Disorganized score mean (sd) | 7.37 (3.3) | 7.62(3.3) | 7.24 (3.4) | 0.171 | 0.96 | 0.87–1.05 | 0.370 |
| Insight Birchwood total score, mean (sd) | 8.96 (2.84) | 8.48 (2.9) | 9.22 (2.8) | 0.003 | 0.87 | 0.79–0.95 | |
| Insight illness awareness Birchwood subscore, mean (sd) | 2.70 (1.37) | 2.58 (1.4) | 2.77 (1.4) | 0.139 | 0.97 | 0.77–1.23 | 0.984 |
| Insight symptoms awareness Birchwood subscore, mean (sd) | 3.01 (1.20) | 2.87 (1.3) | 3.09 (1.2) | 0.073 | 0.99 | 0.78–1.25 | 0.993 |
| Insight needs for treatment subscore, mean (sd) | 3.25 (0.96) | 3.01 (1.1) | 3.38 (0.9) | <0.001 | 0.58 | 0.43–0.78 | <0.001 |
| Lifetime history of suicide attempt (%) | 139 (29.3) | 62 (37.1) | 77 (25.1) | 0.006 | 1.88 | 1.11–3.21 | 0.016 |
| Body Mass Index, mean (sd) | 26.63 (5.5) | 27.19 (6.1) | 26.32 (5.1) | 0.132 | 1.03 | 0.98–1.07 | 0.146 |
| Tardive dyskinesia (AIMS score), mean (sd) | 0.97 (2.2) | 0.95 (2.2) | 1.12 (2.4) | 0.242 | |||
| Akathisia (BAS score ≥2) (%) | 73 (15.9) | 30 (41.1) | 43 (58.9) | 0.296 | |||
| Extrapyramidal symptoms (SARS score), mean (sd) | 0.27 (0.4) | 0.27 (0.3) | 0.27 (0.4) | 0.855 | |||
| Substance use disorder | |||||||
| Lifetime alcohol use disorder, n (%) | 126 (28.8) | 62 (40.8) | 64 (22.4) | <0.001 | 2.58 | 1.36–4.96 | 0.031 |
| Lifetime cannabis use disorder, n (%) | 161 (35.2) | 74 (45.4) | 87 (29.5) | <0.001 | 1.83 | 0.96–3.48 | 0.073 |
| Treatment | |||||||
| Clozapine, n (%) | 72 (16.5) | 22 (14.2) | 50 (17.9) | 0.324 | |||
| Long-acting antipsychotic, n (%) | 64 (14.51) | 23 (14.7) | 41 (14.4) | 0.918 | |||
| First-generation antipsychotic, n (%) | 20 (4.6) | 7 (4.5) | 13 (4.6) | 0.951 | |||
| Second-generation antipsychotic, n (%) | 403 (92.6) | 143 (92.3) | 260 (92.9) | 0.818 | |||
| Chlorpromazine equivalent, mean (sd) | 544.31 (518.5) | 613.02 (626.8) | 507.47 (441.8) | 0.307 | |||
| Antidepressant, n (%) | 109 (25.1) | 36 (23.2) | 73 (26.1) | 0.511 | |||
| Benzodiazepine, n (%) | 99 (22.8) | 35 (22.6) | 64 (22.9) | 0.975 | |||
| Number of psychotropic medications, mean (sd) | 2.58 (1.48) | 2.67 (1.6) | 2.52 (1.4) | 0.561 | |||
Significant associations are in bold.
PANSS Positive and Negative Syndrome Scale, AIMS Abnormal Involuntary Movements Scale, BAS Barnes Akathisia Scale, SARS Simpson and Angus Rating Scale.
aaOR: adjusted odds ratio (adjusted for Age, PANSS positive score, PANSS negative score, PANSS excitation score, PANSS depressive score, PANSS disorganized score, suicide, lifetime alcohol use disorder, lifetime cannabis use disorder, Insight symptoms awareness birchwood subscore, Insight illness awareness birchwood subscore, Insight need for treatment subscore, and Body Mass Index).