Abstract WP167: Clinical Characteristics and Outcomes of Mixed Cerebral Small Vessel Disease According to the CLAS-ICH Classification

Abstract

Objectives: Mixed location intracerebral hemorrhages/ microbleeds (CMBs) (mixed ICH) is referred to as potential hypertensive arteriolosclerosis/cerebral amyloid angiopathy (CAA) combination, reflecting small vessel disease (SVD) burden. We assess the clinical features in patients with mixed ICH. Methods: We utilized data from a prospective registry, which consecutively enrolled patients diagnosed with acute ICH between January 2011 and December 2021. Patients with ICH were classified into subtypes according to the CLAS-ICH classification: hypertensive arteriolosclerosis ([HTN]-ICH), CAA-ICH, mixed ICH, genetic SVD, and secondary causes. The clinical data of patients with mixed ICH were compared to those with HTN-ICH or CAA-ICH. The outcome measure was unfavorable functional outcomes defined as mRS score of 5-6 at 90-day. Results: Of 2127 patients with ICH (mean age 70±13 years, 57% male), 1374 (65%) had HTN-ICH, 141 (6%) had CAA-ICH, 409 (19%) had mixed ICH, none (0%) had genetic SVD, 203 (10%) had secondary causes. Patients with mixed ICH were older (75±11 vs. 69±13 years) and had a high frequency of CMBs (68% vs. 25%), had lower initial SBP (176±32 vs. 184±30 mmHg) and initial NIHSS (12 [4-21] vs. 14 [7-23]) and more hematoma volume (17 [6–52] vs. 11 [4–24] ml), compared to those with HTN-ICH (all P<0.001). There were no significant differences in hypertension, dyslipidemia, and diabetes. When comparing patients with mixed ICH to those with CAA-ICH, they were younger (75±11 vs. 78±8 years) and had a high frequency of male (54% vs 33%), hypertension (95% vs. 36%) and diabetes (14% vs. 5%) and had higher initial SBP (176 ± 32 vs. 160 ± 29 mmHg) and less hematoma volume (17 [6–52] vs. 44 [18–84] ml)(all P<0.001). There was no significant difference in unfavorable outcomes between mixed ICH and HTN-ICH (32% vs. 31%, p>0.1), while the outcomes for mixed ICH were lower than those for CAA-ICH (32% vs. 44%, p=0.004). In multivariate analysis adjusting for covariates, there was no significant difference in unfavorable outcomes between mixed SVD-ICH and CAA-ICH (odds ratio 1.19 [95% CI, 0.66–2.13]). Conclusions: Mixed ICH harbors similar features of hypertensive SVD rather than CAA. The rates of disability and mortality were comparable across the groups.