Timely outpatient follow-up and readmission after discharge are common quality indicators in psychiatric care, but their association varies in previous research. We aimed to examine whether the impact of outpatient follow-up and other factors on readmission risk evolves over time in people with non-affective psychotic disorder (NAP).

The Finnish Quality of Care Register includes all people diagnosed with NAP since January 2010. Here, we followed patients with a hospital discharge between 2017 and 2021 until readmission, death, or up to 365 days. Time of the first outpatient follow-up appointment, length of stay (LOS), number of previous hospitalizations, psychosis diagnosis, substance use disorder (SUD), residential status, economic activity, gender, age, year, and region were included. Follow-up time was divided into five periods: week 1, weeks 2–4, weeks 5–13, weeks 14–25, and weeks 26–52, and each period was analyzed separately with Cox regression.

Of the 29 858 discharged individuals, 54.1% had an outpatient follow-up within a week. A total of 10 623 (35.6%) individuals were readmitted. Short LOS increased the readmission risk in the first four weeks, whereas lack of outpatient follow-up raised the risk (adjusted HRs between 1.15 (95% CI 1.04–1.26) and 1.53 (1.37–1.71) in weeks 5–52. The number of previous hospitalizations remained a consistent risk factor throughout the follow-up, while SUD increased risk after 4 weeks and living without family after 13 weeks.

Risk factors of readmission vary over time. These temporal patterns must be considered when developing outpatient treatment programs.

Several multivariate algorithms have been developed for predicting psychosis, as attempts to obtain better prognosis prediction than with current clinical high-risk (CHR) criteria. The models have typically been based on samples from specialized clinics. We evaluated the generalizability of 19 prediction models to clinical practice in an unselected adolescent psychiatric sample.

In total, 153 adolescent psychiatric patients in the Helsinki Prodromal Study underwent an extensive baseline assessment including the SIPS interview and a neurocognitive battery, with 50 participants (33%) fulfilling CHR criteria. The adolescents were followed up for 7 years using comprehensive national registers. Assessed outcomes were (1) any psychotic disorder diagnosis (n = 18, 12%) and (2) first psychiatric hospitalization (n = 25, 16%) as an index of overall deterioration of functioning.

Most models improved the overall prediction accuracy over standard CHR criteria (area under the curve estimates ranging between 0.51 and 0.82), although the accuracy was worse than that in the samples used to develop the models, also when applied only to the CHR subsample. The best models for transition to psychosis included the severity of positive symptoms, especially delusions, and negative symptoms. Exploratory models revealed baseline negative symptoms, low functioning, delusions, and sleep problems in combination to be the best predictor of psychiatric hospitalization in the upcoming years.

Including the severity levels of both positive and negative symptomatology proved beneficial in predicting psychosis. Despite these advances, the applicability of extended psychosis-risk models to general psychiatric practice appears limited.

We investigated whether psychosis risk symptoms predicted psychiatric service use using seven-year register follow-up data.

Our sample included 715 adolescents aged 15–18, referred to psychiatric care for the first time. Psychosis risk symptoms were assessed with the Prodromal Questionnaire (PQ) at the beginning of the treatment. We assessed the power of the overall PQ as well as its positive, negative, general, and disorganized psychosis risk symptom factors in predicting prolonged service use. Baseline psychiatric diagnoses (grouped into 7 categories) were controlled for. Based on both inpatient and outpatient psychiatric treatment after baseline, adolescents were divided into three groups of brief, intermittent, and persistent service use.

Stronger symptoms on any PQ factor as well as the presence of a mood disorder predicted prolonged service use. All of the PQ factors remained significant predictors when adjusted for baseline mood disorder and multimorbidity.

In a prospective follow-up of a large sample using comprehensive mental health records, our findings indicate that assessing psychosis risk symptoms in clinical adolescent settings at the beginning of treatment could predict long-term need for care beyond diagnostic information. Our findings replicate the previous findings that positive psychosis risk symptoms are unspecific markers of severity of psychopathology. Also psychosis risk symptoms of the negative, disorganization, and general clusters are approximately as strongly associated with prolonged psychiatric service use in the upcoming years.