Objective To investigate the correlation of serum osteoprotegerin (OPG) and calcium levels with cerebral microbleeds in patients with acute ischemic stroke.

Methods A total of 97 patients with acute ischemic stroke were selected as the study subjects and divided into cerebral microbleed (group 31 patients with) and non-cerebral microbleed (group 66 patients) based on the results of susceptibility-weighted imaging. Demographic data and laboratory examination indicators were collected from the two groups, and serum OPG and calcium levels were measured. The levels of serum OPG and calcium were compared between patients with different degrees of lesion and bleeding sites. Spearman rank correlation analysis was used to determine the correlations of serum OPG and calcium with cerebral microbleeds. Multivariate Logistic regression analysis was conducted to explore the influencing factors of cerebral microbleeds. Receiver operating characteristic (ROC) curves were plotted to assess the predictive value of serum OPG and calcium for cerebral microbleeds.

Results Significant differences were observed in age, proportions of patients with drinking and hypertension as well as diabetes, systolic blood pressure, diastolic blood pressure, and serum OPG and calcium levels between the cerebral microbleed group and the non-cerebral microbleed group (P < 0.05). Multivariate Logistic regression analysis revealed that older age, history of alcohol consumption, history of hypertension, high systolic blood pressure, and high OPG level were independent risk factors for cerebral microbleeds (OR=1.480, 1.330, 1.843, 1.632, 1.652; P < 0.05), while high calcium level was an independent protective factor for cerebral microbleeds (OR=0.721, P < 0.05). The AUC values for the prediction of cerebral microbleeds in acute ischemic stroke patients using serum OPG or calcium alone, and their combination were 0.853, 0.825, and 0.921, respectively, with the combined prediction showing higher value than the individual prediction (Z=2.895, 3.138; P < 0.05). Spearman rank correlation analysis revealed a positive correlation between serum OPG and the severity of cerebral microbleeds (r_s=0.736, P < 0.05) and a negative correlation between calcium and the severity of cerebral microbleeds (r_s=-0.752, P < 0.05). No significant differences were observed in serum OPG and calcium levels between patients with cerebral microbleeds in different locations (P > 0.05).

Conclusion Elevated serum OPG and reduced calcium levels are observed in patients with acute ischemic stroke and cerebral microbleeds. The levels of serum OPG and calcium are closely related to the severity of cerebral microbleeds, and early combined detection can effectively predict the risk of cerebral microbleeds.