Association of HbA1c with functional outcome by ischemic stroke subtypes and age

Jihyun Jeong; Jae Kyung Park; Young Ho Koh; Jong-Moo Park; Hee-Joon Bae; Sang-Moon Yun

doi:10.3389/fneur.2023.1247693

Association of HbA1c with functional outcome by ischemic stroke subtypes and age

Front Neurol. 2023 Sep 28:14:1247693. doi: 10.3389/fneur.2023.1247693. eCollection 2023.

Authors

Jihyun Jeong^{1

2}, Jae Kyung Park³, Young Ho Koh³, Jong-Moo Park⁴, Hee-Joon Bae⁵, Sang-Moon Yun⁶

Affiliations

¹ Department of Biostatistics, Korea University College of Medicine, Seoul, Republic of Korea.
² Division of Injury Prevention and Control, Bureau of Chronic Disease Prevention and Control, Korea Disease Control and Prevention Agency, Cheongju-si, Republic of Korea.
³ Division of Brain Diseases Research, Department of Chronic Disease Convergence Research, Korea National Institute of Health, Cheongju-si, Republic of Korea.
⁴ Department of Neurology, Uijeongbu Eulji Medical Center, Eulji University School of Medicine, Uijeongbu-si, Republic of Korea.
⁵ Department of Neurology, Cerebrovascular Center, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
⁶ Division of Cardiovascular Disease Research, Department of Chronic Disease Convergence Research, Korea National Institute of Health, Cheongju-si, Republic of Korea.

Abstract

Objectives: To determine whether high HbA1c levels are related to short-and long-term functional outcomes in patients with ischemic stroke (IS) and whether this association differs according to the IS subtype and the patient's age.

Methods: The data of 7,380 IS patients admitted to 16 hospitals or regional stroke centers in South-Korea, between May 2017 and December 2019, were obtained from the Clinical Research Collaboration for Stroke-Korea-National Institute of Health database and retrospectively analyzed. Among these patients, 4,598 were followed-up for one-year. The HbA1c levels were classified into three groups (<5.7, 5.7 to <6.5%, ≥6.5%). Short-and long-term poor functional outcomes were defined using the modified Rankin Scale score of 2 to 6 at three-months and one-year, respectively. IS subtypes were categorized according to the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) classification.

Results: There was an association between higher HbA1c (≥6.5%) and poor functional outcomes at three-months in all patients (three-months; OR, 1.299, 95% CI 1.098, 1.535, one-year; OR, 1.181, 95% CI 0.952, 1.465). When grouped by age, the associations after both 3 months and 1 year observed in younger adult group (<65 years), but not in group aged 65 years and older (three-months; <65 years OR, 1.467, 95% CI 1.112, 1.936, ≥65 years OR, 1.220, 95% CI 0.987, 1.507, p for interaction = 0.038, one-year; <65 years OR, 1.622, 95% CI 1.101, 2.388, ≥65 years OR, 1.010, 95% CI 0.778, 1.312, p for interaction = 0.018). Among younger adult group, the higher HbA1c level was related to short-and long-term functional loss in patients with the small vessel occlusion subtype (three-months; OR, 2.337, 95%CI 1.334, 4.095, one-year; OR, 3.004, 95% CI 1.301, 6.938). However, in patients with other TOAST subtypes, a high HbA1c level did not increase the risk of poor outcomes, regardless of the age of onset.

Conclusion: High HbA1c levels increase the risk of short-and long-term poor functional outcomes after IS onset. However, this association differs according to stroke subtype and age. Thus, pre-stroke hyperglycemia, reflected by HbA1c, may be a significant predictor for a poor prognosis after ischemic stroke, particular in young- and middle-aged adults.

Keywords: HbA1c; functional loss; hyperglycemia; ischemic stroke subtype; stroke prognosis.