Whole Blood Serotonin Levels and Platelet 5-HT2A Binding in Autism Spectrum Disorder.
Elizabeth Aaron, Alicia Montgomery, Xinguo Ren and 8 others
PMID 30927179WHAT IT FOUND
Whole blood serotonin was higher in 110 people with autism than in 18 controls.
Platelet serotonin receptor binding did not differ between groups, but its relationship with blood serotonin differed by diagnosis.
Key findings
01Mean whole blood serotonin was 253.9 ng/mL in the autism group and 169.0 ng/mL in the control group, and the autism group was significantly higher.
02Mean platelet 5-HT2A specific binding was 24.5 fmoles/mg/protein in the autism group and 26.2 fmoles/mg/protein in controls, and the difference was not significant.
03The relationship between platelet 5-HT2A specific binding and whole blood serotonin differed by diagnosis: binding predicted whole blood serotonin in controls, but not in the autism group.
STILL TO COME
How it was doneWhat they found
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
Only 18 control individuals were analysed, and the authors stated the study had limited power to detect a difference in platelet 5-HT2A binding. The control sample was small and the sample was predominantly Caucasian. The authors said this limits generalisability to other populations. The autism group was younger than the control group on average, so age was included in the regression analyses. Many participants lacked platelet 5-HT2A specific binding values: 100 participants did not have those values. The study measured peripheral blood serotonin and platelet binding but not brain serotonin, so it did not connect the findings to the presumed brain basis of autism symptoms. The paper did not report how the blood measures related to autism symptoms.
The easy way to misread this
Do not treat higher whole blood serotonin as a clinical sign that should change therapy. The study compared group averages, did not test treatment, and did not link the blood measures to symptoms.