HbA1c is associated with increased all-cause mortality in the first year after acute ischemic stroke

Abstract

Objectives:

To assess the association between baseline HbA1c and the poor outcomes within 1 year after acute ischemic stroke.

Methods:

Acute ischemic stroke patients with HbA1c values at baseline (n = 2186) were selected from the abnormal glucose regulation in patients with acute stroke across China study (ACROSS). Logistic regressions were performed to assess the association between HbA1c quartiles (<5·5% [37 mmol/mol], 5·5 to <6·1% [37 to <43 mmol/mol], 6·1 to <7·2% [43 to <55 mmol/mol], and ≥7·2% [≥55 mmol/mol]) and the poor outcomes within 1 year. Poor outcomes were defined as all-cause mortality (modified Rankin scale [mRS] = 6) and poor functional outcome (mRS [2–6]).

Results:

The risk for all-cause mortality was significantly increased in HbA1c level >5·5% [>37 mmol/mol] when compared to HbA1c quartile <5·5% [<37 mmol/mol] and dramatically increased to two to three times higher in the highest HbA1c quartile ≥7·2% [>55 mmol/mol] (1-year all-cause mortality model, odds ratios [ORs] were 1·07, 1·01, and 2·45, P for trend 0·009). After the further analysis with previous diabetes mellitus (DM) and post-stroke insulin use stratified, the risk of mortality was increased across the HbA1c levels (P for trend 0·020) and dramatically augmented in HbA1c ≥7·2% [>55 mmol/mol] in patients without a history of DM and without post-stroke insulin use.

Discussion:

Elevated HbA1c (from 5·5% [37 mmol/mol]) presenting pre-stroke glycemia status has a significant trend in increasing the risk of 1-year all-cause mortality. HbA1c ≥7·2% (>55 mmol/mol) is an independent risk predictor for 1-year all-cause mortality after acute first-ever ischemic stroke. Such an association might be altered by glycometabolism status.