Primary care consultation patterns for a prespecified set of symptoms may be used to identify patients who later develop a psychotic illness, according to research published in JAMA Network Open. This research, which identifies 12 symptoms nonspecific with psychosis that are associated with a later psychotic diagnosis, may help physicians distinguish patients who may benefit from further assessment.
The nested case-control study examined primary care consultation data from 530 UK primary care practices and included 11,690 adults with a psychosis diagnosis and 81,793 control patients. Researchers chose prespecified symptoms from literature that included attention-deficit/hyperactivity disorder-like symptoms, bizarre behavior, blunted affect, problems with cannabis, depressive symptoms, role functioning problems, social isolation, mania symptoms, obsessive-compulsive disorder-like symptoms, disordered personal hygiene, sleep disturbance, cigarette smoking, and suicidal behavior (including self-harm).
Conditional logistic regression revealed the association between symptoms and case-control status in 5 years preceding diagnosis. Twelve of the symptoms listed (with the exception of disordered personal hygiene) were associated with a later psychotic diagnosis, with the strongest association being for suicidal behavior. The positive predictive values for suicidal behavior, calculated using the Bayes theorem, were 33.0% in men aged 24 years and younger and 19.6% in women aged 25 to 34 years. In addition, pairs of symptoms were associated with an increase in positive predictive value, and consultation rates were elevated in cases and increased 3 months before diagnosis.
The study was limited by a small female preponderance of cases, possible unrecorded cases, and the case-control structure of the research database, which did not allow researchers to investigate whether the prodromal symptoms in the analyses were specifically indicative of psychosis.
Researchers conclude that, “These findings are the first stage in the development and validation of a prognostic model of psychosis for primary care by providing candidate predictors and counter the generally held belief that individuals with emerging psychosis do not seek help from a medical professional.” This information may help physicians identify which patients are more likely to develop psychosis.
Sullivan SA, Hamilton W, Tilling K, Redaniel T, Moran P, Lewis G. Association of primary care consultation patterns with early signs and symptoms of psychosis. JAMA Netw Open. 2018;1(7):e185174.