LOS ANGELES – Hallucinations in patients with schizophrenia do not appear to remain stable in later life, a longitudinal cohort study has shown.
The findings also suggest that the disappearance and reemergence of hallucinations in later life are modulated by negative symptoms and community integration, Dr. Audra Yadack reported in a poster at the annual meeting of the American Association for Geriatric Psychiatry.
The point prevalence of hallucinations was fairly low among the 103 patients in the study who were followed for a mean of 52 months, with only 33% of patients affected at baseline and 26% affected at follow-up, but because of symptom fluctuations, 43% had hallucinations during the study period.
"Notably, only 16% of patients had hallucinations at both [baseline] and [follow-up], 57% never had hallucinations, 10% developed hallucinations, and 17% no longer had hallucinations [at follow-up]," wrote Dr. Yadack of the State University of New York Downstate Medical Center, Brooklyn.
Four baseline factors were found on logistic regression analysis to be significant predictors of hallucinations at follow-up, including the presence of hallucinations (odds ratio, 9.66); nonremitting negative symptoms, as indicated by a Positive and Negative Syndrome Scale score of greater than 3 on all seven negative symptoms (OR, 9.07); a lower Community Integration Questionnaire score (OR, 0.50); and use of more mental health services (OR, 1.04).
Furthermore, the presence of hallucinations at baseline did not significantly correlate with any clinical variables at follow-up, and higher Community Integration Questionnaire scores and more confidantes at baseline were significantly associated with the disappearance of hallucinations between baseline and follow-up, she noted.
Patients included in this analysis were a mean age of 61 years and developed schizophrenia prior to age 45 years. The presence of hallucinations was assessed using self-reports of auditory, visual, or olfactory symptoms on a semistructured questionnaire.
The findings, which are important given the paucity of data on the prevalence of, course of, and factors associated with hallucinations in older adults with schizophrenia, highlight several predictors of hallucinations that could serve as points for clinical intervention, according to Dr. Yadack.
"One key measure, community integration – a measure of independent living, life quality, and social engagement – seemed to have a bidirectional relationship with hallucinations," she wrote, explaining that community integration predicted hallucinations at baseline, and hallucinations at baseline predicted lower community integration at follow-up.
Negative symptoms at baseline also were predictors of hallucinations at follow-up – a finding that is consistent with those in younger samples showing that negative and positive symptoms might co-occur, she noted, adding that "total mental health services were associated with a greater likelihood of hallucinations, suggesting that identifying age-appropriate and targeted strategies for enhancing community integration and diminishing negative symptoms may help increase the likelihood of the remission of hallucinations."
This study was funded by grants from the National Institute of General Medical Sciences.