The severity of schizophrenia patients’ negative symptoms might predict their service engagement after their first episode of psychosis, according to a study published in The Journal of Nervous and Mental Disease.
Researchers also found poorer engagement, as rated by clinicians, linked to greater positive and negative symptoms, greater general psychopathology, and poorer premorbid adolescent social adjustment (early and late) before regression analysis, reported Angus MacBeth, Ph.D., D.Clin.Psy., of the University of Glasgow, and his associates (J. Nerv. Ment. Dis. 2013;201:359-64 [doi: 10.1097/NMD.0b013e31828e0e19]).
Yet no correlation between duration of psychosis and engagement was found, and "only negative symptoms emerged as a significant independent predictor of engagement" following multiple regression analysis.
The researchers used a cross-sectional cohort design that included 64 people presenting with first-episode psychosis to early intervention psychosis services in two cities in Scotland. The sample comprised 43 men and 21 women, predominantly white and British. A plurality of patients was diagnosed with schizophrenia (28 patients). Among the others, 14 had bipolar disorder, 10 had schizoaffective disorder, 6 had persistent delusional disorder, 4 had schizophreniform disorder, and 2 had mania with psychotic symptoms.
Patients were included if they were in their first 12 months of treatment for first-episode psychosis and they did not have substance abuse, head injury, or an organic disorder determined to be the main cause of their psychotic symptoms.
In addition to the use of the Positive and Negative Syndrome Scale (PANSS) to assess schizophrenia symptoms, the researchers used the Premorbid Adjustment Scale (PAS), the Service Engagement Scale (SES), and an unstructured interview with the individual (when no longer floridly psychotic), and/or a caretaker or loved one to establish duration of psychosis.
The PAS measured prepsychosis academic and social functioning during the first three of four life stages: childhood, early adolescence, late adolescence, and adulthood. The four subscales of the Service Engagement Scale completed by clinicians were availability, collaboration, help-seeking, and treatment adherence.
Men and women scored similarly on the total clinician-rated SES score and the help-seeking and availability subscales. However, women scored more poorly (higher score) on the subscales of collaboration and treatment adherence (mean 3.63 for females, 1.87 for males, t = –2.42, df = 45, P = .02). Women also reported "significantly greater impairment in [adolescent] social functioning than male participants did" (t = –2.233, df = 40, P = .031).
The authors found the post–regression-analysis association with negative symptoms "puzzling," given that previous studies on predictors of disengagement have not found such a correlation with negative symptoms. They suggested a possible conflation of negative symptoms with social functioning as a potential underlying mechanism for the association.
"Perhaps negative symptoms are more likely to predict engagement, because they reflect a more contemporaneous measure of social functioning than the PAS does," the authors wrote. "This does not negate the role of premorbid adjustment but suggests that engagement difficulties may reflect both immediate and more longstanding issues."
They wrote that social and interpersonal malfunctioning might have preceded the frank psychotic symptoms and then become more conspicuous after positive symptoms fade, especially given the correlation found between negative symptoms and poor premorbid social adjustment.
It’s unclear what the implications of poorer engagement portend. The authors noted that patients might be at risk of disengagement if they present poorer levels of engagement, or "engagement difficulties may be a marker for difficulties in adapting to the diagnosis of psychosis and its associated impact."
The study was limited by its exploratory cross-sectional design and the small sample size. Further, the patients’ participation during nonacute illness (though not asymptomatic) and their responsiveness to early intervention may mean the participants "represent a higher functioning group of individuals, with a corresponding reduction of variance in the duration of psychosis and lower levels of positive and negative symptoms," than do other cohorts.
The authors said their findings underscore "the importance of clear and comprehensive measurement of premorbid and onset variables in first-episode psychosis."
Dr. MacBeth was supported by a PhD scholarship from the University of Glasgow Medical School. The authors reported no disclosures.