Table 1.
Sample Characteristics and Comparison of Adherent and Nonadherent Patientsa
| Variable | Total (N = 1,052) | Adherent (n = 531) | Nonadherent (n = 521) | P Value |
| Patient demographics | ||||
| Female | 77.6 | 75.7 | 79.5 | .144 |
| Age, y | 42.08 (10.63) | 43.17 (10.49) | 40.98 (10.66) | < .001 |
| White | 85.8 | 86.1 | 85.6 | .831 |
| College graduate | 24.1 | 29.2 | 19.0 | < .001 |
| Physical health measures | ||||
| Alcohol use | 55.1 | 47.3 | 63.2 | < .001 |
| Body mass index, kg/m2 | 31.76 (8.93) | 32.02 (8.94) | 31.50 (8.91) | .353 |
| Comorbid count | ||||
| None | 19.0 | 16.8 | 21.3 | .060 |
| 1 | 23.3 | 23.2 | 23.4 | .923 |
| 2 | 22.0 | 21.7 | 22.3 | .812 |
| 3+ | 35.7 | 38.4 | 33.0 | .067 |
| SF-8 physical score | 40.57 (9.95) | 39.90 (10.38) | 41.25 (9.46) | .028 |
| Bipolar disease characteristics | ||||
| No. of depressive episodes | 8.39 (11.08) | 7.41 (8.70) | 9.39 (13.0) | .004 |
| No. of manic episodes | 6.54 (9.30) | 5.62 (8.24) | 7.47 (10.19) | .001 |
| BASIS-24 total score | 1.82 (0.75) | 1.63 (0.76) | 2.01 (0.70) | < .001 |
| Depression/functioning | 2.14 (0.97) | 1.94 (0.98) | 2.34 (0.91) | < .001 |
| Interpersonal relationships | 1.79 (0.94) | 1.63 (0.95) | 1.95 (0.91) | < .001 |
| Self-harm | 0.83 (1.0) | 0.67 (0.93) | 0.99 (1.04) | < .001 |
| Emotional lability | 2.36 (1.0) | 2.13 (1.04) | 2.60 (0.90) | < .001 |
| Psychosis | 1.00 (1.00) | 0.81 (0.92) | 1.20 (1.03) | < .001 |
| Substance abuse | 0.69 (0.92) | 0.54 (0.86) | 0.85 (0.96) | < .001 |
| Bipolar treatment characteristics | ||||
| LUNSERS score | ||||
| Total (excluding red herrings) | 55.58 (28.13) | 51.36 (28.39) | 59.88 (27.21) | < .001 |
| Extrapyramidal side effects | 9.00 (6.13) | 8.33 (6.23) | 9.67 (5.97) | < .001 |
| Other autonomic side effects | 5.99 (4.33) | 5.42 (4.29) | 6.57 (4.30) | < .001 |
| Psychic side effects | 20.17 (8.84) | 18.50 (8.96) | 21.88 (8.38) | < .001 |
| Miscellaneous side effects | 5.33 (3.13) | 4.99 (3.14) | 5.66 (3.09) | < .001 |
| Anticholinergic side effects | 6.04 (4.07) | 5.70 (3.90) | 6.38 (4.22) | .007 |
| Allergic reaction | 3.16 (3.21) | 3.06 (3.23) | 3.27 (3.19) | .289 |
| Hormonal side effects | 5.90 (4.24) | 5.36 (4.13) | 6.45 (4.28) | < .001 |
| Red herrings | 9.90 (7.10) | 9.60 (7.19) | 10.21 (7.00) | .166 |
| Satisfaction With Antipsychotic Medication scale score | 7.71 (1.36) | 8.09 (1.31) | 7.31 (1.29) | < .001 |
| Second-generation antipsychotics | 47.0 | 46.7 | 47.2 | .868 |
| First-generation antipsychotics | 1.7 | 0.9 | 2.5 | .052 |
| Mood stabilizers | 83.3 | 84.1 | 82.3 | .424 |
| Selective serotonin reuptake inhibitors | 16.8 | 15.8 | 17.8 | .379 |
| Serotonin-norepinephrine reuptake inhibitors | 6.2 | 5.8 | 6.5 | .643 |
| Dopamine-norepinephrine reuptake inhibitors | 7.2 | 7.5 | 6.9 | .696 |
| Other antidepressants | 3.6 | 4.9 | 2.3 | .024 |
| Sedative hypnotics | 5.9 | 5.5 | 6.3 | .548 |
| Monotherapy use | 52.2 | 54.0 | 50.3 | .222 |
| Economic outcomes | ||||
| WPAI absenteeism | 15.47 (25.59) | 15.74 (27.05) | 15.23 (24.30) | .882 |
| WPAI presenteeism | 41.49 (27.17) | 36.96 (27.24) | 45.58 (26.56) | .020 |
| WPAI overall work impairment | 34.75 (22.98) | 30.28 (22.65) | 38.78 (22.6) | .006 |
| WPAI activity impairment | 46.16 (29.91) | 39.91 (29.23) | 51.83 (29.51) | .002 |
| Visited the emergency room | 15.87 | 11.68 | 20.15 | < .001 |
| No. of emergency room visits | 0.31 (0.93) | 0.20 (0.77) | 0.42 (1.06) | < .001 |
| Hospitalized | 11.69 | 8.10 | 15.36 | < .001 |
| Days hospitalized | 0.98 (5.25) | 0.87 (6.22) | 1.09 (4.04) | .504 |
a
Categorical variables are shown as percentages, with χ2 used to assess significance. Continuous variables are shown as mean (SD), with t tests used to assess significance.
Abbreviations: BASIS-24 = 24-item Behavior and Symptom Identification Scale, LUNSERS = Liverpool University Neuroleptic Side-Effect Rating Scale, SF-8 = Medical Outcomes Study 8-item Short-Form Health Survey, WPAI = Work Productivity and Activity Impairment.