OBJECTIVES: There is now some evidence that alterations in fatty acids may play a role in the pathophysiology of autism. The aim of the present study was to examine whether autism is accompanied by abnormalities in the composition of the polyunsaturated fatty acids (PUFAs) in plasma phospholipids.
METHODS: The plasma phospholipid omega-3 (3) and omega-6 (6) PUFA fractions and the 3/6 ratio were measured in 16 high-functioning male youngsters with autism (age 12-18) and 22 healthy volunteers. Group mean differences were assessed by means of analysis of variance (ANOVA).
RESULTS: In autism there was a significant increase in the fraction of C22:6-3 (docosahexaenoic acid, DHA) and an increase in the total 3/6 ratio.
DISCUSSION: The results of this study suggest that an increase of the plasma phospholipid 3 PUFAs, in particular DHA, and of the total 3/6 ratio may take part in the pathophysiology of autism. One hypothesis is that an increase of 3 PUFAs may cause alterations in the serotonergic turnover and the immune response system, both known to be associated with autism. Caution must be exercised against highly concentrated 3 PUFAs supplementation.