Læknablaðið - 15.10.1992, Blaðsíða 40

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LÆKNABLAÐIÐ
I Minnesota í Bandaríkjunum hefur nýgengi
iktsýki verið áætlað 7,4 til 15,8 ný tilfelli á
ári fyrir hverja 10.000 íbúa eldri en 40 ára
(27). Sé miðað við þessar niðurstöður eru
einstaklingar með hækkun á IgM RF í fjór-
til sjöfalt aukinni áhættu á að fá iktsýki, en
einstaklingar með hækkun á IgG eða IgA RF
í allt að ellefufaldri áhættu. Notuð voru sömu
greiningarskilmerki í bandarísku rannsókninni
og í okkar rannsókn (18).
I hnotskurn benda niðurstöður rannsóknar
okkar til að hækkun á IgA RF og IgG RF hafi
sterkari tengsl við iktsýki og áhættu á að fá
þann sjúkdóm heldur en hækkun á IgM RF.
ÞAKKIR
Starfsfólki Rannsóknarstöðvar Hjartavemdar,
Rannsóknastofu í ónæmisfræði og sýkladeildar
Landspítalans eru færðar þakkir fyrir ýmiss
konar aðstoð við framkvæmd rannsóknarinnar
og mælingar á sýnum. Vísindasjóður styrkti
framkvæmd þessarar rannsóknar.
SUMMARY
The prevalence and incidence of rheumatoid
arthritis (RA) was evaluated in 135 rheumatoid
factor (RF) positive and 194 RF negative
individuals.
It was found that the prevalence of RA was
higher in individuals with elevation of IgG RF
or IgA RF compared with IgM RF. Furthermore,
the prevalence of RA was markedly higher in
individuals with elevation of two or three RF
isotypes compared with RF negative individuals
or subjects with elevation of only one RF isotype.
Symptom free individuals with elevation of IgA RF
or IgG RF showed an increased risk for developing
RA during a mean observation period of 9.3 years.
This was not found for elevation of IgM RF.
It is concluded that the IgA RF and IgG RF
isotypes have a closer association with RA than
IgM RF.
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