Atrial fibrillation in cancer patients who develop stroke

Abstract

Background: Acute ischemic stroke (Stroke) and transient ischemic attacks (TIA) are known complications in cancer patients and those with atrial fibrillation (AF). The role AF plays in Stroke/TIA in the setting of cancer is unclear. The purpose of this study was to assess the relationship between AF and Stroke/TIA in cancer patients.

Methods: We conducted a case-control study comparing all patients who developed Stroke/TIA from 2014 to 2019 following a cancer diagnosis at King Hussein Cancer Center (KHCC), matched to Stroke/TIA-free controls based on age, gender, and cancer site.

Results: Two hundred seventy-two patients were included (136 per group). The mean age was 63.95 ± 13.06 and 57% were females. The Stroke/TIA group had more AF at the time of event (14% vs. 4%, OR: 4.25, 95%-CI: 1.39 - 17.36) and had a larger proportion of death on study conclusion (OR: 9.4, 95%-CI: 3.74 - 23.64). On conditional logistic regression, patients in the Stroke/TIA group had higher odds of: AF (OR: 7.93, 95%-CI: 1.6 - 39.18), ischemic stroke before cancer diagnosis (OR: 9.18, 95%-CI: 2.66 - 31.74), being on active cancer treatment (OR: 3.11, 95%-CI: 1.46 - 6.62), dyslipidemia (OR: 3.78, 95%-CI: 1.32 - 10.82), and renal disease (OR: 4.25, 95%-CI: 1.55 - 11.63). On another conditional logistic regression model built to assess the role of the CHA₂DS₂-VASc score, a score of >=2 in males and >=3 in females significantly increased the risk of developing Stroke/TIA in cancer patients (OR: 2.45, 95%-CI: 1.08 - 5.58).

Conclusion: AF, previous ischemic stroke, active cancer treatment, dyslipidemia, and renal disease are independent risk factors for Stroke/TIA and a higher CHA₂DS₂-VASc score significantly increases the risk in cancer patients regardless of AF.

Keywords: Atrial fibrillation; Cancer; Ischemic stroke; Transient ischemic attack.

Fig. 1

Forest Plot of Analysis of Multiple Clinical Variables and the Likelihood of stroke/TIA Occurring in Cancer Patients. Multivariate analysis was carried out using conditional logistic regression to study the effects of the clinical variables on the likelihood of having Stroke/TIA. The points represent the Odds Ratio, and the lines represent the 95% confidence interval. Points in blue represent an OR >1 indicating that cases with Stroke/TIA are more likely to have the corresponding clinical characteristic. Lines (CIs) which do not cross the null value of 1 represent statistical significance

Fig. 2

Forest plot representing CHA₂DS₂-VASc score contribution to Stroke/TIA in cancer patients. Another conditional logistic regression model was built to assess the effect of the CHA₂DS₂-VASc score on the likelihood of having Stroke/TIA in cancer patients. Variables included in computing the CHA₂DS₂-VASc score were excluded from the model. A CHA₂DS₂-VASc score of >=2 in males and >=3 in females significantly increases the risk of Stroke/TIA in cancer patients independent of AF diagnosis. The points represent the Odds Ratio, and the lines represent the 95% confidence interval. Points in blue represent an OR >1 indicating that cases with Stroke/TIA are more likely to have the corresponding clinical characteristic. Lines (CIs) which do not cross the null value of 1 represent statistical significance