Changes in Gray Matter Density in Fibromyalgia Correlate with Changes in Dopamine Metabolism

An article has been e-published ahead of print in the Journal of Pain linking Fibromyalgia Syndrome with changes in the brain and suggesting that alterations in dopamine metabolism may contribute to these changes.

The work was carried out by a team of researchers at Louisiana State University Health Sciences Center, including Dr Patrick Wood, a member of FibroAction's Professional Advisory Board and the originator of the Dopamine Theory of Fibromyalgia.

The article notes that Fibromyalgia Syndrome has been associated with alterations in brain morphometry (i.e. changes in the brain) and abnormal dopaminergic neurotransmission. Also, evidence from preclinical models has demonstrated that dopamine plays a role in promoting neuronal integrity. The team of researchers sought to confirm previous findings of reduced gray matter density in subjects with Fibromyalgia Syndrome and to determine whether variations in dopamine metabolism might affect gray matter density.

Voxel-based morphometry was used to evaluate anatomical magnetic resonance imaging data from 30 female FM subjects in comparison with 20 age- and gender-matched healthy control subjects.

In addition, data from a subset of subjects from both groups who had previously participated in a positron emission tomography study using radiolabeled DOPA (n = 14; 6 Fibromyalgia Syndrome subjects and 8 control subjects) was used to determine whether correlation might exist between gray matter density and dopamine metabolism.

The researchers found a significant reduction in gray matter density within certain areas of the brain: the bilateral parahippocampal gyri, right posterior cingulate cortex, and left anterior cingulate cortex. In addition, a positive correlation was demonstrated between an index of dopamine metabolism from the ventral tegmental area wherein cell bodies of corticolimbic projection neurons originate and gray matter density, specifically in the bilateral parahippocampal gyri and left pregenual cortex.

The article notes that:

"The current results confirm our previous findings that [Fibromyalgia Syndrome] is associated with altered brain morphometry. Alterations in dopamine metabolism might contribute to the associated changes in gray matter density."

Perspective

Fibromyalgia is associated with reductions in gray matter density within brain regions ostensibly involved in phenomena related to the disorder, including enhanced pain perception, cognitive dysfunction, and abnormal stress reactivity. Given mounting evidence of abnormal dopaminergic neurotransmission associated with the disorder, the strong correlation between dopamine metabolism and gray matter density provides insight as to the pathophysiology that might contribute to these changes.

Dr Wood features on the DVD'Fibromyalgia: Show Me Where It Hurts' discussing the Dopamine Theory of Fibromyalgia. This DVD will shortly be available through FibroAction. Please check back soon if you are interested in seeing this.

To read the full article, please click here.

References:

1. Wood PB, Glabus MF, Simpson R, Patterson JC 2nd. Changes in Gray Matter Density in Fibromyalgia: Correlation With Dopamine Metabolism. J Pain. 2009 Apr 22. [Epub ahead of print]