12 Questions used to assess patient education recall
We used the 12-item Patient Education Questionnaire developed by Lin and colleagues4 to assess what patients remembered their physicians telling them about their antidepressants. We asked patients to respond to the following questions:
- Were you given a simple explanation of how the medicine works? (yes/no)
- Were you told how long it would take before the medicine would start to have a noticeable effect? (yes/no—if yes, how long were you told it would take?)
- Were you told how long to expect to continue taking the medication? (yes/no)
- Which of the following instructions were you given about taking the medicine?
- –Keep taking it even if you start to feel better (yes/no)
- –Don’t stop taking it without checking with the office (yes/no)
- –Take it on a daily basis without interruption (yes/no)
- Did your doctor discuss side effects that are common when taking the medicine? (yes/no)
- Were you given advice on how to manage minor side effects? (yes/no)
- Were you advised on what to do if you experienced major side effects? (yes/no)
- Were you advised about when or how long you might have side effects? (yes/no)
- Were you asked about prior use of a similar medication? (yes/no).
Results
The enrolled sample was predominantly female, white, and had a mean age of 45 years. More than half had some college education, were married (or living with a partner), and were employed full- or part-time (TABLE 1).
Clinical characteristics On average, patients reported 2 medical conditions (moderate symptoms of depression, and moderate impairment in psychosocial functioning). All participants referred to the study had been prescribed an antidepressant for the treatment of depression by their primary care physician.
TABLE 1
Baseline demographic, clinical characteristics, and diagnoses of enrolled sample (N=191)
| DEMOGRAPHICS | |
| Mean (SD) age | 45.1 (15.9) |
| % Female | 70.7 |
| % White | 93.7 |
| % Employed full/part-time | 52.9 |
| % Married or living with partner | 53.9 |
| % Greater than high school education | 55.5 |
| CLINICAL CHARACTERISTICS | |
| Mean (SD) BDI | 19.5 (10.3) |
| Mean (SD) MOS PCS | 44.6 (11.5) |
| Mean (SD) MOS MCS | 30.7 (10.7) |
| Mean (SD) number of current medical conditions | 2.0 (1.6) |
| MOOD DIAGNOSIS | |
| No diagnosis | 13.6% |
| Major depression only | 36.6% |
| Major depression + dysthymia | 30.4% |
| Partial remission of major depression | 6.3% |
| Partial remission of major depression + dysthymia | 7.9% |
| Dysthymia only | 1.6% |
| Minor depression only | 3.7% |
| COMORBIDITY (MOOD + ANXIETY) | |
| –Major depression or dysthymia + panic or generalized anxiety disorder | 27.7% |
| –Any mood disorder + any anxiety disorder | 50.3% |
| BDI, Beck Depression Inventory; MOS MCS, Medical Outcomes Study Short Form Mental Component Score; MOS PCS, Medical Outcomes Study Short Form Physical Component Score. | |
Clinical characteristics
On average, patients reported 2 medical conditions (moderate symptoms of depression, and moderate impairment in psychosocial functioning). All participants referred to the study had been prescribed an antidepressant for the treatment of depression by their primary care physician.
At the initial interview, 67% of patients met Diagnostic and Statistic Manual, 4th ed10 (DSM-IV) criteria for major depression. Approximately 37% met criteria for major depression alone, while 30% met criteria for major depression and dysthymia. Four percent met the criteria for minor depression, 6% were in partial remission of major depression, and 14% of participants did not meet criteria for a DSM-IV mood disorder. Comorbid anxiety disorders were common in this sample; 28% of participants with major depression or dysthymia had comorbid generalized anxiety disorder or panic disorder.
More than 80% of the antidepressants the patients were taking were selective serotonin reuptake inhibitors (SSRIs). Citalopram (31%), fluoxetine (19%), paroxetine (15%) and sertraline (13%) were the most common (TABLE 2).
TABLE 2
Antidepressants taken at baseline (N=191)
| ANTIDEPRESSANT | N (%) |
|---|---|
| Citalopram (Celexa) | 60 (31.4%) |
| Fluoxetine (Prozac) | 36 (18.8%) |
| Paroxetine (Paxil) | 28 (14.7%) |
| Sertraline (Zoloft) | 24 (12.6%) |
| Bupropion (Wellbutrin) | 15 (7.9%) |
| Escitalopram (Lexapro) | 13 (6.8%) |
| Venlafaxine (Effexor) | 10 (5.2%) |
| Nefazodone | 2 (1.0%) |
| Trazodone (Desyrel) | 2 (1.0%) |
| Phenelzine (Nardil) | 1 (0.5%) |
Adherence declines over 3 months
Overall, adherence to antidepressants significantly decreased over time. While adherence as measured by the percentage of prescribed doses taken was good (82%) at month 1, it showed a significant linear decrease to 69% at 3 months (P<.0001).
When the more stringent measure of adherence was examined—ie, percentage of days with correct intake and timing—adherence was even poorer, decreasing nonlinearly over time. Adherence at month 1 was only 55%; and decreased to 43% at 3 months (linear: P <.001; quadratic: P=.036). Our findings indicate that by the end of the first 3 months of treatment, between about one-third and one-half of the patients were nonadherent to their regimen.
Univariate predictors of adherence
Adherent patients are older
Medication adherence of at least 80% was used as a cutpoint: ≥80% was considered adherent, <80% nonadherent. Univariate analyses (t-tests and chi-square tests) indicated that the following patient characteristics were significantly associated with taking the correct number of prescribed antidepressant doses at least 80% of the time within the first 3 months of treatment.