Clinical characteristics and outcomes of intracerebral haemorrhage in young vs older adults: insights from the INTERACT3 trial
Journal
European Stroke Journal
ISSN
2396-9873
Date Issued
2026-06
Author(s)
Khan, Maria
Ouyang, Menglu
Wasay, Mohammad
Ma, L
Hu, Xin
Chen, Xiaoying
Billot, Laurent
Li, Qiang
de Silva, Asita
Thang, Nguyen Huy
Wahab, Kolawole W
Pandian, Jeyaraj D
Pontes-Neto, Octavio M
Abanto, Carlos
Arauz, Antonio
You, Chao
Song, Lili
Anderson, Craig S
Robinson, Thompson
Miranda, J Jaime
Anderson, Craig S
You, Chao
Song, Lili
Parry-Jones, Adrian
Sprigg, Nikola
Durrans, Sophie
Harris, Caroline
Bamford, Ann
Smith, Olivia
Type
Article
Abstract
Introduction
ICH is a severe form of stroke with increasing global burden. Although more common in older adults, ICH in younger individuals (≤50 years) is a clinically distinct but understudied subgroup. This secondary analysis of the INTERACT3 trial compared baseline characteristics, management and outcomes between younger and older ICH patients.
Patients and methods
INTERACT3 was a stepped-wedge, cluster-randomised trial conducted in 122 hospitals across 10 countries (2017–2021), evaluating a bundled care intervention for acute ICH. This sub-study analysed 7031 patients and compared demographics, imaging features, in-hospital treatment and 6-month outcomes between age groups. Primary outcomes were functional status (mRS), mortality and quality of life (EQ-5D-3L). Outcomes were analysed using generalised linear-mixed models accounting for clustering by hospital (random effect) and fixed effects for time period and cluster treatment assignment, with additional adjustment for pre-specified patient-level covariates.
Results
Of 7031 patients, 1351 (19.2%) were aged ≤ 50 years. Younger patients were more often male (70.8% vs 62.4%, P < .0001), had higher body mass index (BMI) (25.3 vs 23.8 kg/m2, P < .0001) and were more likely to smoke (36.1% vs 21.4%) and consume alcohol (33.2% vs 13.3%). Despite having slightly larger haematoma volumes (18.0 vs 15.0 mL, P < .0001), younger patients had significantly better outcomes, with lower 6-month mortality (9.1% vs 16.6%; adjusted OR 0.42; 95% CI, 0.33–0.54) and reduced rates of death or disability (46.5% vs 57.8%; OR 0.56; 95% CI, 0.48–0.65). A significant age-by-treatment interaction was observed (P = .0251).
Conclusion
Younger ICH patients demonstrated a distinct risk profile and better recovery, and benefiting more from bundled care interventions. These findings highlight the importance of early, intensive management and tailored prevention strategies targeting modifiable lifestyle risks in younger populations.
ICH is a severe form of stroke with increasing global burden. Although more common in older adults, ICH in younger individuals (≤50 years) is a clinically distinct but understudied subgroup. This secondary analysis of the INTERACT3 trial compared baseline characteristics, management and outcomes between younger and older ICH patients.
Patients and methods
INTERACT3 was a stepped-wedge, cluster-randomised trial conducted in 122 hospitals across 10 countries (2017–2021), evaluating a bundled care intervention for acute ICH. This sub-study analysed 7031 patients and compared demographics, imaging features, in-hospital treatment and 6-month outcomes between age groups. Primary outcomes were functional status (mRS), mortality and quality of life (EQ-5D-3L). Outcomes were analysed using generalised linear-mixed models accounting for clustering by hospital (random effect) and fixed effects for time period and cluster treatment assignment, with additional adjustment for pre-specified patient-level covariates.
Results
Of 7031 patients, 1351 (19.2%) were aged ≤ 50 years. Younger patients were more often male (70.8% vs 62.4%, P < .0001), had higher body mass index (BMI) (25.3 vs 23.8 kg/m2, P < .0001) and were more likely to smoke (36.1% vs 21.4%) and consume alcohol (33.2% vs 13.3%). Despite having slightly larger haematoma volumes (18.0 vs 15.0 mL, P < .0001), younger patients had significantly better outcomes, with lower 6-month mortality (9.1% vs 16.6%; adjusted OR 0.42; 95% CI, 0.33–0.54) and reduced rates of death or disability (46.5% vs 57.8%; OR 0.56; 95% CI, 0.48–0.65). A significant age-by-treatment interaction was observed (P = .0251).
Conclusion
Younger ICH patients demonstrated a distinct risk profile and better recovery, and benefiting more from bundled care interventions. These findings highlight the importance of early, intensive management and tailored prevention strategies targeting modifiable lifestyle risks in younger populations.