Hyperthyroidism linked to young adult stroke risk
MedWire News: Young adults with hyperthyroidism may have an increased risk for stroke, shows a large prospective study.
“There are hypercoagulability, hypofibrinolysis, and endothelial dysfunctions in hyperthyroidism, and all may contribute to the increased risk for thromboembolism,” comment Herng-Ching Lin (Taipei Medical University, Taiwan) and team in the journal Stroke.
They note that stroke etiology is never determined in about a third of young adults who suffer stroke.
The absolute numbers of strokes were low in the current study, in which participants were aged an average of just 32 years. Overall, 31 (1.0%) of 3176 patients with hyperthyroidism suffered stroke within the first 5 years after diagnosis, compared with 167 (0.6%) of 25,408 controls monitored during the same period.
But this equated to a significant 44% increase in stroke risk for patients with hyperthyroidism, after accounting for demographics and vascular risk factors, including whether the participants were using anti-arrhythmic drugs.
Patients with hyperthyroidism suffered stroke a median of 1004 days after their hyperthyroidism diagnosis; therefore, half of the strokes occurred after this time.
“Our study indicates hyperthyroidism and antithyroid therapy may be associated with short-term and long-term cerebrovascular consequences,” say Lin and colleagues.
“These results are in accordance with previous studies suggesting that hyperthyroidism and radioiodine therapy are associated with increased long-term vascular risk.”
They conclude: “Considering that 12 to 18 months is the optimum duration of antithyroid drug therapy, efforts to prevent stroke should last even after restoration of euthyroidism.”
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By Eleanor McDermid