Supplementary Material for: TRENDS IN HOSPITAL DISCHARGES WITH PRIMARY DIAGNOSIS OF CEREBRAL VENOUS THROMBOSIS BY AGE AND SEX IN SPAIN

Background: Recent studies show an increase in the incidence of Cerebral Venous Thrombosis (CVT), with varying patterns across age and sex subgroups. This study analyzes hospital discharges with a primary diagnosis of CVT in Spain, examining year-on-year trends, demographic variations, and in-hospital mortality rates.

Methods: A retrospective analysis of CVT cases from 2005 to 2021 was conducted using data from the Hospital Morbidity Survey provided by the National Statistics Institute of Spain. CVT incidence rates were standardized using the European Standard Population.

Results: Among 76,793,382 hospital discharges, 4,293 were primarily diagnosed with CVT, with a mean age of 45.1 years (SD 20.4). Women represented 61.4% of CVT diagnoses. The standardized incidence increased from 0.41 cases per 100,000 inhabitants in 2005 to 0.84 in 2021. The rise occurred mainly among older adults—especially men over 50 (+4.6 cases/year) and women over 50 (+3.1)—whereas younger women, despite the highest incidence rates, showed the smallest increase (+0.8). Segmented regression revealed an acceleration in trends after 2016, notably in men over 50 (+8.0/year post-2016 vs. +1.4 pre-2016, p = 0.019), and a reversal in younger women from decline to growth (+10.9/year post-2016, p = 0.074). Time series analysis showed a proportional decrease in younger women (p < 0.001) and a rising relative burden in older men (p < 0.001). Overall, in-hospital mortality was 2.96%, with no significant differences between sexes.

Conclusions: Trends in hospital discharges with a primary diagnosis of CVT in Spain vary by age and sex. Incidence rates have shown an overall increase, primarily driven by rising cases among adults aged ≥50 years—especially men. Although younger women continue to exhibit the highest incidence, their relative contribution has declined over time.