Principios de los medios alternativos de solución de

5.1.2.1 Medication Persistency

Results from the survival analyses showed that patients receiving psychotherapy were less likely to discontinue their medication treatment initially. This protective effect, however, diminished during the first two months of the follow-up, and patients with psychotherapy became more likely to discontinue their treatment after the first two months of the follow-up. Given the average number of psychotherapy visits in this study is 5.4, if we assume patients have an average of one visit per week, their psychotherapy is likely to be ended around the fifth or sixth week following their initial psychosocial treatment. Additionally, we found that around 40% of patients received their first psychotherapy treatment session within the first three months of pharmacotherapy initiation, and most patients had all of their psychotherapy visits within the first 40 days in Aim 1. The finding in Aim 2 that psychotherapy users were more persistent in the first 60 days of the follow-up may reflect the effect of psychotherapy when patients are regularly receiving psychosocial treatments.

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After the first two months, patients may complete their five or six psychosocial treatment sessions and no longer have psychotherapy. Since patients receiving

psychotherapy often have worse mental health conditions (as shown in the descriptive statistic results), they could be less adherent to their regimens than their non-psychotherapy receiving counterparts. This may explain the increased hazard of medication discontinuation for the psychotherapy group after the first two months of the follow-up. Therefore, our result from the survival analysis may indicate that 1) psychotherapy is effective when continuously used, and 2) once patients stop psychotherapy, the effect of psychotherapy lasts only for a short period of time.

The result that patients with psychotherapy had better adherence in the first two months may be also explained by other services provided to the patients that could not be captured in the claims data. As discussed in section 5.1.1, a previous study using MEPS found a high proportion of patients had mental-health related psychotherapy or counseling services during an outpatient visit in 2007.59 Since the definition of psychotherapy in this previous study was ―a treatment technique for certain forms of mental disorders relying principally on talk/conversation between the mental health professional and the patient‖, many of these services can be an informal treatment and thus do not show up in the claims. Given that the patients in our study are new antipsychotic users, they may receive more psychosocial interventions or counseling services that cannot be identified in the claims at the beginning of their antipsychotic treatment, which also explains the better persistency in the first three months of the follow-up.

In addition, the short effect of psychotherapy on medication persistency may simply be due to the underuse of psychotherapy since the effect of psychotherapy usually appears

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after patients received a minimum number of treatments.57, 148 For example, it is suggested that patients need to attend at least ten treatment sessions for psychotherapy in order for psychotherapy to be effective.57, 148 It is reported that only attending one session of treatment may worsen medication adherence.38 Therefore, the patients in our study may not receive enough treatment sessions to make a clinically significant improvement.

Another potential explanation of the lack of effectiveness of psychotherapy after the first two months is that since more than 70% of the first-episode patients will achieve a full remission in the first three to four months,17, 18 psychotherapy initiated after the first three months may have different focus from medication use and therefore has limited effect on medication persistency.

In addition to the effectiveness of psychotherapy use, we found that non-white patients were more likely to stop taking their medications. This may be caused by a lack of access to health care or by different cultural backgrounds, which lead to different perceptions of disease and treatment. We also found that patients living in North Carolina were more likely to discontinue their antipsychotic treatment compared to patients in Illinois, when using a gap excess of 30 days to define discontinuation. However, this effect is not significant when using a gap greater than 15 days to define discontinuation. The slightly higher rate of 30-day discontinuation in North Carolina might be due to the monthly prescription cap (6 prescriptions per month) as in 2003.

Another interesting finding in the Cox model is that patients who had modified their antipsychotic treatment were less likely to experience a discontinuation. This result may indicate that patients receiving psychotherapy have more chances to provide feedback on

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their conditions or treatments to their health care professionals, and therefore, the clinicians can better adjust their regimens, which improves persistency.

5.1.2.2 Medication Switching

The logistic regression models showed that patients with psychotherapy were more likely to switch their antipsychotics using either a 30-day or 15-day window to define switching, and this result remained unchanged in the IV model with a 30-day switching window. Because the use of psychotherapy and medication switching were measured during the same period of time, the results from the naïve model can only be interpreted as an association, not causation. However, our IV results still indicate the use of psychotherapy leads to a higher probability of antipsychotic switching. Since the use of psychotherapy is recommended before and after a change in antipsychotics,39, 40 to facilitate switching, physicians may be more likely to provide psychotherapy to their patients before changing patients’ antipsychotics. Therefore, our findings may indicate that most patients were

receiving psychotherapy before antipsychotic switching, rather than indicating that the use of psychotherapy increases the risk of medication switching.

Similar to the previous discussion in section 5.1.1.1, another potential explanation of the higher chance of switching could be that patients with psychotherapy may have more chances to interact with health care professionals, which provides them more opportunities to discuss the effectiveness of their current medication treatment. As a result, a physician may be more likely to be aware of problems associated with medication treatment for patients with psychotherapy and hence switch these patients to another antipsychotic agent. In this case, the use of psychotherapy serves as a channel for patients to reveal their problems with

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antipsychotic treatment, and the higher chance of medication switching can be viewed as a positive outcome. When we consider medication persistency and switching together, the better medication persistency among patients with psychotherapy may be due to the fact that patients using psychotherapy were more likely to switch to a suitable antipsychotic agent.

5.1.3 Aim 3: The effect of adjunctive psychotherapy use on hospitalizations and treatment