Background: Patient-reported outcome measures (PROM) provide clinicians with information about patients’ perceptions of distress. When linked with treatment and diagnostic registers, new information may be obtained, such as associations with prevalence and service use. This study aimed to examine psychological symptoms among psychiatric outpatients and to investigate treatment-relevant characteristics of symptom-homogeneous classes. Methods: In a cohort study of 2473 (63% female) outpatients, factor mixture modelling (FMM) was used to analyse self-reported symptoms of anxiety and depression before treatment, and the classes association with functional impairment, the prevalence of common mental health disorders (CMHD) and the number of assessments and psychotherapy appointments one year after treatment start. Results: Overall, 22% of patients with a CMHD had an additional comorbid mood/anxiety disorder. This comorbid group reported higher symptoms of anxiety and depression compared to patients with non-comorbid anxiety disorders. FMM revealed three classes: “anxiety and somatic depression” (33%), “mixed depression and anxiety” (40%), and “cognitive depression” (27%). The anxiety and somatic depression class was associated with older age, being single and on sick leave, higher probability of depressive-, anxiety-, and comorbid disorders, having more appointments and higher functional impairment. Although the cognitive depression class had less somatic distress than the mixed depression and anxiety class, they reported more functional impairment and had higher service use. Conclusions: The results demonstrate the clinical relevance of applying FMM to PROM data of depression, anxiety, and functional impairment when linked with treatment registers. Three patient groups emerged, with different symptom patterns. Higher symptom severity did not necessarily imply more functional impairment and service use when subdimensions and latent patient groups were accounted for.

Purpose Health-related quality of life (HRQoL) is an important aspect of mental health outcomes. There are few studies on HRQoL in heterogeneous patient populations seeking help at community mental health services. The aims of the study were to compare how HRQoL, measured by the EuroQol five dimensions with five levels (EQ-5D-5L), was distributed compared to other samples from national and international studies, and to explore what factors are associated with HRQoL. Methods In a cross-sectional study, 1379 Norwegian outpatients reported their HRQoL before starting treatment. Associations with demographic variables, job status, socio-economic status, and use of pain medication were examined using multiple regression analysis. Results Most of the sample, 70% to 90%, reported problems with usual activities, pain/discomfort, and anxiety/depression; 30% to 65% reported that these problems were of a moderate to extreme degree. Forty percent reported problems with mobility, and about 20% reported problems with self-care. The sample’s HRQoL was considerably lower than the general population, and comparable to patient-groups from specialist mental health services. Originating from a developing country, lower level of education, lower yearly household income, being on sick leave or unemployed, and using pain medication were associated with lower HRQoL. Age, gender, and relationship status were not associated with HRQoL. This is the first study to simultaneously examine the unique contribution of these variables in one study. Conclusion The most impacted domains of HRQoL were pain/discomfort, anxiety/depression, and usual activities. Lower HRQoL was associated with several socio-demographic factors and use of pain medication. These findings might have clinical implications and suggest that mental health professionals should routinely measure HRQoL in addition to symptom severity, to identify areas that should be targeted to improve HRQoL.