Relationships among medication adherence, insight, and neurocognition in chronic schizophrenia

Abstract

Aims:In order to improve long-term prognosis in schizophrenia, enhancing medication adherence is essential. The aim of this study was thus to identify the association between medication non-adherence and possible risk factors in a large sample of patients with chronic schizophrenia. Methods:One hundred and four patients with schizophrenia with a disease duration of over 10 years were enrolled in this cross-sectional study. The subjects were assessed with the Scale to Assess Unawareness of Mental Disease-Korean version, the Korean version of the Medication Adherence Rating Scale, a neurocognition battery designed for this study, and the Positive and Negative Symptoms Scale. An ANOVA and multiple regression models were conducted to identify the correlations among variables and the factors that contribute to medication adherence. Results:The adherence score measured on the Korean version of the Medication Adherence Rating Scale was 7.60 ± 2.12; 88 (84.62%) patients were categorized as well-adherent and 16 (15.38%) as poorly adherent to their medication. Patients with good insight were more likely to maintain their medication (P = 0.0005), and better executive function was associated with increased medication adherence (P = 0.0008). Furthermore, fewer depressive symptoms were associated with good medication adherence (P = 0.0304).Conclusions: This study is the first in the Republic of Korea to identify the relationship between medication adherence, insight, and neurocognition in a large sample of patients with chronic schizophrenia. These results could be used to establish a strategy for improving the prognosis of chronic schizophrenia.

Insight in schizophrenia spectrum disorders: relationship with behavior, mood and perceived quality of life, underlying causes and emerging treatments

“…Consistent with this, Misdrahi et al 18 and Lincoln et al 19 found that persons with poor insight were more likely to refuse to take antipsychotic medication, while others have found that groups with lower levels of adherence across cultures have consistently tended to have poorer clinical insight [20][21][22][23] .…”

Why do psychiatric patients stop antipsychotic medication? A systematic review of reasons for nonadherence to medication in patients with serious mental illness

“…Results from a cross-sectional study of Korean patients with chronic schizophrenia reported that poor executive function was a significant predictor of nonadherence; however, other cognitive functions, such as long-term memory, perception, and attention with working memory, were not significant 36. Forgetfulness was the most common reason for nonadherence self-reported by poorly adherent patients with schizophrenia and related disorders in Ethiopia39 and by patients with bipolar disorder 43.…”

“…When a specific domain of insight was assessed, awareness of need for treatment but not awareness of illness was significantly associated with adherence in patients with schizophrenia and schizoaffective disorder 47. Similarly, poor awareness of need for treatment was associated with poor adherence in Korean patients with chronic schizophrenia 36. In contrast, a study from Ethiopia found that awareness of illness and ability to positively reassess experiences/symptoms, but not awareness of need for treatment, were associated with better adherence in patients with schizophrenia 35.…”

“…Most of the studies (88.9%, 32/36) were published between 2006 and 2013, with a range of 3–6 studies published each year during that period. Insight was the most frequently investigated reason for nonadherence, reported in 55.6% (20/36) of the studies, followed by substance abuse (36.1%, 13/36), attitude toward medication (30.5%, 11/36), medication side effects (27.8%, 10/36), and cognitive impairments (19.4%, 7/36; Figure 212,19,20,22–36,38–50,52–55). …”

An integrative model of the impairments in insight in schizophrenia: emerging research on causal factors and treatments

“…As in the case of symptoms, a complicating factor is that poor neurocognition could also contribute to treatment non-adherence, creating another feedback loop through which symptoms and insight could be related. Indeed, a recent study found that better executive functioning and better insight were associated with increased medication adherence [64].…”