Læknablaðið - 15.11.1997, Síða 29

LÆKNABLAÐIÐ 1997; 83
741
hafa tHcy-hækkun vegna fólínsýruskorts eða
erfðagalla.
Bláæðahlið hómósysteinrannsókna hefur
orðið út undan. Samkvæmt forsendum þessara
rannsókna og fyrirliggjandi niðurstöðum er þó
engin ástæða til að ætla annað en hómósystein
stuðli að blóðsegamyndun jafnt í bláæðum og
slagæðum. Fleiri bláæðarannsókna er þörf,
einkum meðferðarrannsókna á sjúklingum
sem fengið hafa endurtekna bláæðasega.
Ekki er enn grundvöllur fyrir almennum
leiðbeiningum varðandi mælingar á tHcy og
túlkun gilda. Það fer þó varla hjá því að menn
velti fyrir sér hvort ekki megi nýta tiltæka
þekkingu í klínískri starfsemi. Varla er umdeil-
anlegt að mæla með nægilegri fólínsýruneyslu
sem telst vera 0,4 mg á dag (135). Höfundur
hefur vanist því að tHcy ungra sjúklinga sé
ntæld í þeim tilfellum þegar ekki er hægt að
skýra fylgikvilla æðakölkunar út frá öðrum
áhættuþáttum og að gildi ofan efri viðmiðunar-
marka séu meðhöndluð með lágum skammti af
fólínsýru. Þegar þetta er ritað er tHcy hvergi
mæld á íslandi.
í stuttu máli bendir flest til að tHcy sé bæði
áhættuþáttur og orsakavaldur æðakölkunar en
ekki er enn vitað hvort tHcy-lækkandi meðferð
dregur úr þróun æðabreytinga.
HEIMILDIR
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