[Follow-up management after PSA testing in 400,000 citizens within the Agency for Health Protection of the Metropolitan Area of Milan].

Objectives to evaluate follow-up patterns after a total prostate-specific antigen (PSA) test performed in the absence of clinical indications among residents of the Agency for Health Protection of the Metropolitan Area of Milan (ATS Milano). Design a cohort of men aged 30-84 years residing in the ATS Milano area who underwent at least one PSA test between 2018-2019 and 2021-2023, followed for subsequent investigations through December 2024. Setting and participants from the administrative and healthcare databases of the ATS Milano, 414,731 individuals who had at least one PSA test during the study period, presumably for screening purposes, were identified. Main outcome measures individual procedures and cumulative follow-up activities within 3, 6, and 12 months from the index PSA test, classified as passive or active, and as conservative (repeat PSA test, ultrasound, or urological visit) or aggressive/therapeutic (CT/MRI imaging, prostate biopsy, or prostate-related hospitalization). Logistic regression was used to estimate the probability of active and aggressive follow-up. Results overall, 58% of men had no follow-up procedures within the first year, particularly among those with low PSA values, while the proportion remained above 30% among men with PSA >=4 ng/mL. Among those who underwent follow-up, 84% followed a conservative pathway. At one year, among men aged 50-69 years (55.7% of the total population) with PSA >=3 ng/mL, 38.8% had no follow-up, while 18.7% underwent an aggressive procedure, compared with about 5% among those with PSA <3 ng/mL. Within three months, the most frequent procedures were urological consultation (10.0%) and ultrasound (9.3%). The probability of active follow-up increased with age (including advanced age), index PSA value, >=3 comorbidities, and socioeconomic deprivation. Older age, PSA >= 4ng/mL, and Italian citizenship were associated with a higher likelihood of an aggressive approach. Conclusions the high rate of active follow-up among older adults (70-84 years) with multiple comorbidities, even with a lower use of aggressive procedures, indicates the value of an organised programme aimed at concentrating interventions on individuals who are most likely to benefit.