Background: Cognitive impairment is frequently found in patients with thalassemia. Advanced age, chronic anemia, iron overload, and hypercoagulability are contributing factors for cognitive dysfunction. 

Objective:  To determine the prevalence of cognitive impairment and clinical predictive factors in patients with thalassemia.

Material and methods: A cross-sectional study was conducted in adult patients aged 18 years or older at Srinagarind Hospital, Khon Kaen University, Thailand, from March to October 2021. The RUDAS test was used to assess cognitive functions. The patients were classified into two groups based on their educational levels; group A (≤ 6 years of education) and group B (> 6 years of education). The RUDAS score < 23/30 in group A and < 24/30 in group B indicated cognitive impairment. A stepwise backward multiple regression analysis with logarithmic transformations was used to demonstrate the clinical predictive factors for cognitive impairment.

Results: Of 150 patients, cognitive impairment defined by the RUDAS test was found in 28 patients (18.7%). Increased age (adjusted odds ratio [AOR] of 0.9), low activities of daily living (ADL) score (AOR of 0.7), and serum ferritin (AOR of 0.9) were associated with low RUDAS score, which indicated cognitive impairment. Contrary, the interval of blood transfusion (AOR of 1.2) was associated with an increased RUDAS score.

Conclusions: Assessment of cognitive function using the RUDAS test showed a high prevalence of cognitive impairment among thalassemic patients. Aging, low ADL score, and iron overload were significant associated factors with this condition. Cognitive screening should be performed in high-risk patients to modify their risk factors, which may prevent or suspend the progression of cognitive impairment.

Keywords: The RUDAS test, Cognitive impairment, Thalassemia