Post-Stroke Fatigue May Be Associated with the Promoter Region of a Monoamine Oxidase A Gene Polymorphism

Abstract

Background: Post-stroke fatigue (PSF) is a common sequela of stroke. Despite reports of serotonergic involvement in the etiology of PSF, the potential contribution of serotonergic genes in the development of PSF needs to be investigated. Methods: A total of 373 patients, who experienced ischemic stroke for PSF, were evaluated 3 months after the stroke. PSF was assessed using the Fatigue Severity Scale. The genomic DNA collected and stored in a -70°C freezer was genotyped for 6 polymorphisms in genes associated with serotonin synthesis (tryptophan hydroxylase 1 (TPH1) A218C, TPH2 rs10879355, and TPH2 rs4641528), transport (the promoter region of the serotonin transporter protein), and catabolism (the 30-bp functional variable number tandem repeat) polymorphism in the promoter region of monoamine oxidase A (MAO-A). Results: Among the 373 patients, 164 (44%) had PSF. All patients were ethnic Koreans. Of the 6 polymorphisms examined, only one marker, that is, low-activity MAO-A was associated with PSF (p < 0.05) in female patients. Multiple logistic regression analyses showed that post-stroke depression (PSD; 95% CI 1.561-14.323, p = 0.006) and low MAO-A activity (95% CI 0.166-0.722, p = 0.005) were factors associated with PSF in female patients, whereas only PSD (95% CI 5.511-65.269, p = 0.000) was associated with PSF in male patients. Conclusions: Our findings suggest that PSF may be associated with a genetic polymorphism involving MAO-A, at least in female stroke patients.