Short-Term Effects of Metformin and Diabetic Diet on Cognitive Functions in Newly Diagnosed Type 2 Diabetes Mellitus Patients

Abstract

Objective: We aimed to investigate the effects of metformin or dietary treatment on cognitive functions in newly diagnosed Type 2 Diabetes Mellitus patients. Materials and Methods: Our study was designed prospective. The study included 64 healthy controls and 72 newly diagnosed Type 2 Diabetes Mellitus patients. Metformin treatment for thirty-seven patients and dietary treatment for thirty-five patients were administered by a single endocrinologist. Rey Auditory Verbal Learning Test, Rey Complex Figure Test, Digit Span Test and Trail Making Test for all patients were performed at the time of diagnosis and at the sixth- month of the treatment by a blinded neurologist. Results: At the time of diagnosis, we observed that verbal memory scores in the diabetes group were significantly lower than healthy controls (p= 0.03 in dietary, p= 0.044 in metformin group). Sixth- month evaluation revealed that dietary treatment improved only immediate verbal memory scores (p= 0.041). Metformin treatment, along with verbal memory scores, also significantly improved visual spatial memory (p = 0.014) and processing memory and executive functions (p = 0.036 and p = 0.001). Conclusion: We determined a statistically significant improvement in verbal memory, visual spatial memory and processing speed & executive function scores with metformin treatment, while dietary treatment improved only verbal memory scores.

Keywords

• diabetes mellitus
• metformin
• trail making test
• neuropsychological tests

Yeni Tanı Tip 2 Diabetes Mellitus Hastalarında Metformin ve Diabetik Diyetin Bilişsel Fonksiyonlara Kısa Dönem Etkisi

Abstract

Amaç: Çalışmamızda yeni tanı konmuş Tip 2 Diabetes Mellitus hastalarında metformin veya diyet tedavisinin bilişsel işlevler üzerindeki etkilerini araştırmayı amaçladık. Gereç ve Yöntem: Çalışmamız prospektif olarak tasarlandı. Çalışmaya 64 sağlıklı kontrol ve 72 yeni tanı Tip 2 Diabetes Mellitus hastası dahil edildi. Otuz yedi hasta için metformin tedavisi ve otuz beş hasta için diyet tedavisi tek bir endokrinolog tarafından başlandı. Tüm hastalar için Rey İşitsel Sözel Öğrenme Testi, Rey Kompleks Figur Testi, Sayı Dizisi Testi ve İz Sürme Testi, tanı anında ve tedavinin altıncı ayında tedaviye kör bir nörolog tarafından yapıldı. Bulgular: Sözel bellek skorlarının tanı anında diyabet grubunda sağlıklı kontrollerden anlamlı derecede düşük olduğunu gözlemledik (diyet p = 0.03, metformin p = 0.044). Altıncı ay değerlendirilmesinde diyet tedavisinin sadece anlık sözel bellek skorlarını anlamlı iyileştirdiği görüldü (p = 0,041). Metformin tedavisi sözel bellek skorları ile beraber ayrıca görsel uzamsal belleği (p = 0.014) ve işlem belleği ve yürütücü fonksiyonları (p = 0.036 ve p = 0.001) anlamlı iyileştirmişti. Sonuç: Yeni tanı alan Tip 2 Diyabetes Mellitus hastalarında metformin tedavisi ile sözel bellek, görsel uzamsal bellek ve işleme hızı ve yürütücü işlev skorlarında istatistiksel olarak anlamlı bir iyileşme tespit ederken, diyet tedavisi sadece sözel bellek skorlarını iyileştirdi.

Keywords

• Diabetes Mellitus
• Metformin
• İz sürme testi
• Nöropsikolojik test

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