Abstract
<title>Abstract</title> <p> <bold>Background.</bold> Patients with psychotic disorders face a life expectancy 15–20 years shorter than the general population. Describing how general practitioner (GP), psychiatric, and cardiological ambulatory care combine across patients' trajectories may inform cardiovascular care guidelines in this population. <bold>Methods.</bold> We conducted a retrospective cohort study using a 2% representative sample (ESND) of the French National Health Data System (SNDS), linking individual-level reimbursement data for ambulatory and hospital care. Patients newly identified with psychotic disorders between 2016 and 2020 were followed for three years. Weekly care sequences were constructed from outpatient contacts (general practice, psychiatry, cardiology). After computing optimal matching distances, patients were clustered using partitioning around medoids, evaluating solutions with 3–6 clusters on statistical and clinical criteria. Classification and regression trees (CART) identified visit-count thresholds (at 1, 2 and 3 years) differentiating care pathway groups. <bold>Results.</bold> The study included 4,410 incident patients. Although clustering quality indices favoured k = 3 and k = 4, a 5-pattern solution was retained on clinical grounds. The five patterns were: (1) <italic>general practice</italic> dominant (39.1%), characterised by sustained GP attendance without specialist follow-up; (2) <italic>ambulatory psychiatric care</italic> (19.0%), combining regular GP and frequent outpatient psychiatric contacts; (3) <italic>cardiological follow-up</italic> (6.0%), older patients with the only substantial cardiology follow-up; (4) <italic>low-intensity general practice</italic> (15.5%), marked by progressive disengagement from GP and near-absent outpatient psychiatric care; and (5) <italic>disengaged</italic> (20.3%), with near-total absence from ambulatory records. CART identified four consultation-volume thresholds assigning trajectory membership at three years (overall agreement 66.5%). <bold>Conclusions.</bold> This nationwide claims-based analysis identified five clinically interpretable patterns of ambulatory care after identification of psychotic disorders. Specialist cardiology follow-up was uncommon. Whether these patterns are associated with cardiovascular outcomes remains to be determined. <bold>Trial registration:</bold> The study was registered with the French Health Data Hub registry (Ref. No. 30029504). </p>