MURAT İLHAN ATAGÜN, Özlem Devrim BALABAN, KÜRŞAT ALTINBAŞ, Sema YEŞİLYURT, Devran TAN

İki uçlu bozuklukta bilişsel işlev bozukluklarının klinik belirleyicileri ve bilişsel ara fenotipler

Bilişsel işlev bozuklukları iki uçlu bozukluğun klinik düzelme dönemlerinde dahi hastaları etkilemektedir. Başta sözel öğrenme, sözel bellek ve yürütücü işlev bozuklukları olmak üzere faal bellek, dikkat, dikkati sürdürme ve işlem hızı iki uçlu bozuklukta öne çıkan alt bilişsel alanlardır. Sözel öğrenme ve sözel bellek hastaların yanında birinci derece akrabalarda da en fazla etkilenmiş işlevler olduklarından hastalıkla ilgili bir özellik olabilir, dolayısıyla bilişsel ara fenotip kavramına en uygun aday gibi görünmektedirler. Psikotik hastalık dönemlerinin olup olmaması, geçirilen hastalık dönemi tip ve sayıları, hastalığın başlangıç yaşı ve hastalık süresi bilişsel kayıpları etkilediği belirlenmiş klinik parametrelerdir. İki uçlu bozuklukların erken başlangıçlı formları, tip II bozukluk, yaşlılık ve komorbidite varlığı durumlarında bilişsel işlevlerin nasıl etkilendiği ile ilgili sınırlı sayıda araştırma bulunmaktadır. Ayrıca ilaçların bilişsel işlevleri kalitatif ve kantitatif olarak nasıl etkilediği ile ilgili yeterli ve tutarlı kanıt bulunmamaktadır. Hastaların birinci derece akrabalarında bilişsel kayıpların görülmesi ve kayıpların ailesel benzerlik göstermesi bilişsel işlevler için kalıtım göstergesi olabilir, bu nedenle araştırmaların desenlenmesinde genetik modellerin dikkate alınması önemli veriler sağlayabilir.

Clinic determinents of cognitive dysfunctions and cognitive endophenotypes in bipolar disorder

Cognitive dysfunctions influence patients with bipolar disorder even when they are clinically remitted. Verbal learning, verbal memory and executive functions foremost, working memory, (sustained) attention and processing speed are substantial cognitive domains in bipolar disorder. Dysfuntions in verbal learning and memory might be observed in first degree relatives as well; and thus seem to be best candidates for the cognitive endophenotype concept. Prior psychotic episodes, numbers and types of episodes, age of illness onset and duration of illness are clinical parameters seem to influence cognitive functions. There are relatively limited numbers of researches about cognitive dysfunctions in early onset forms, old age, type II disorder and comorbidity aspects of bipolar disorders. Results from the researches regarding qualitative and quantitative effects of medications on cognition are inconsistent. Cognitive deficits of first degree relatives and familial resemblance of deficits might be indicators of heritability of cognitive functions, therefore taking genetic models into account in designs of researches may provide considerable data.

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