Predictors of medication adherence in patients with schizophrenia and bipolar disorder.

OBJECTIVE: To investigate potential risk factors for medication non-adherence in patients with schizophrenia and bipolar disorder. METHOD: A total of 255 patients underwent clinical assessments, neurocognitive testing and blood sampling. The patients were divided into groups of 'No', 'Partial' or 'Full' adherence. Relationships to different risk factors were analyzed. RESULTS: In schizophrenia, use of illicit substances, alcohol and poor insight were related to worse adherence. Schizophrenia patients with No adherence did better on tests of executive functioning, verbal learning and memory and had higher IQ than patients with better adherence. There were higher levels of autonomic side effects in the non-adherence group, but body mass index was lower in the Partial adherence group than in the Full adherence group. In the bipolar disorder patients, there was an association between the use of illicit substances and alcohol and poor adherence. We found no relationship between adherence behavior and neurocognition in the bipolar disorder group. CONCLUSION: Substance use is an important risk factor for non-adherence in patients with schizophrenia and bipolar disorder. Poor insight is also a risk factor in schizophrenia. The results suggest that cognitive dysfunction is not a risk factor for non-adherence in these diagnostic groups.

The level of illicit drug use is related to symptoms and premorbid functioning in severe mental illness.

OBJECTIVE: There is conflicting data on drug abuse and outcome in severe mental illness. This study aims to investigate if the amount of illicit psychoactive drug use is related to symptom load or premorbid functioning across diagnosis in patients with severe mental illness. METHOD: Symptom load, sociodemographic status, premorbid functioning and the level of use of illicit psychoactive drugs were assessed in 423 subjects with schizophrenia or bipolar disorder in a cross-sectional study. RESULTS: High amount of illicit drug use was associated with poorer premorbid academic functioning. In schizophrenia, there was a significant positive association between amount of drug use and severity of psychiatric symptoms. The association between symptom load and drug use was significant after controlling for premorbid functioning. CONCLUSION: The results suggest a direct association between the quantity of current drug use and more severe symptoms in schizophrenia. Poor premorbid functioning was related to high amount of use, but did not explain the difference in symptom load.

Illicit drug use in patients with psychotic disorders compared with that in the general population: a cross-sectional study.

OBJECTIVE: Prevalence estimates of illicit drug use in psychotic disorders vary between studies, and only a few studies compared prevalence estimates with those in the general population. METHOD: Cross-sectional study comparing 148 stable-phase patients with schizophrenia or bipolar disorder with 329 representative general citizens of Oslo. A total of 849 patients from the same hospital department in the same time period constituted a patient reference group. RESULTS: Lifetime illicit drug use was 44% higher (P < 0.001) in study patients than in the general population sample; while lifetime use of amphetamine/cocaine was 160% higher (P < 0.001). No differences were found between user groups for sociodemographic characteristics. CONCLUSION: Patients with psychotic disorders in stable phase had a markedly higher lifetime use of any illicit substance, especially amphetamine/cocaine, than the general population. They also seemed to use drugs more periodically. The same sociodemographic characteristics were associated with increased illicit drug use in both groups.

Differences in prevalence and patterns of substance use in schizophrenia and bipolar disorder.

BACKGROUND: Schizophrenia and bipolar disorder have partly overlapping clinical profiles, which include an over-representation of substance-use behaviour. There are few previous studies directly comparing substance-use patterns in the two disorders. The objective of the present study was to compare the prevalence of substance use in schizophrenia and bipolar disorder, and investigate possible differences in pattern and frequency of use. METHOD: A total of 336 patients with schizophrenia or bipolar spectrum disorder from a catchment area-based hospital service were included in a cross-sectional study. In addition to thorough clinical assessments, patients were interviewed about drug-use history, habits and patterns of use. The prevalence and drug-use patterns were compared between groups. RESULTS: Patients with bipolar disorder had higher rates of alcohol consumption, while schizophrenia patients more often used centrally stimulating substances, had more frequent use of non-alcoholic drugs and more often used more than one non-alcoholic drug. Single use of cannabis was more frequent in bipolar disorder. CONCLUSION: The present study showed diagnosis-specific patterns of substance use in severe mental disorder. This suggests a need for more disease-specific treatment strategies, and indicates that substance use may be an important factor in studies of overlapping disease mechanisms.

The effect of gender on emotion perception in schizophrenia and bipolar disorder.

OBJECTIVE: Impaired emotion perception is documented for schizophrenia, but findings have been mixed for bipolar disorder. In healthy samples females perform better than males. This study compared emotion perception in schizophrenia and bipolar disorder and investigated the effects of gender. METHOD: Visual (facial pictures) and auditory (sentences) emotional stimuli were presented for identification and discrimination in groups of participants with schizophrenia, bipolar disorder and healthy controls. RESULTS: Visual emotion perception was unimpaired in both clinical groups, but the schizophrenia sample showed reduced auditory emotion perception. Healthy males and male schizophrenia subjects performed worse than their female counterparts, whereas there were no gender differences within the bipolar group. CONCLUSION: A disease-specific auditory emotion processing deficit was confirmed in schizophrenia, especially for males. Participants with bipolar disorder performed unimpaired.