RESEARCH - Hippocampal dysfunction may explain fibromyalgia syndrome symptoms

[Guest guest]

Hippocampal Dysfunction May Explain Fibromyalgia Syndrome Symptoms

NEW YORK (Reuters Health) Aug 28 - A paper in the July issue of the

Journal of Rheumatology suggests that hippocampus dysfunction may

explain some symptoms of fibromyalgia syndrome.

Dr. Yasser Emad, of Cairo University, Egypt, and colleagues used

proton magnetic resonance spectroscopy (1H-MRS) to examine hippocampal

function in 15 patients with fibromyalgia syndrome and 10 healthy

age-matched controls.

Using 1H-MRS, the researchers calculated hippocampal levels of

N-acetyl aspartate (NAA), choline, creatine and their ratios and

compared the findings between groups. All study participants also

underwent assessments of sleep patterns, cognitive function, and

symptoms of depression. The number of tender points was assessed in

all patients, and a visual analog scale was used to measure pain.

Patient age averaged 35.7 years, and mean disease duration was 18.1

months. All patients had cognitive functional impairment on the Mini

Mental State Examination, eight (35.5%) were depressed on the basis of

the Hamilton Depression Scale, and nine (60%) had sleep disturbances.

None of the control subjects had cognitive impairment, depression, or

sleep disturbance.

" NAA levels of the right and left hippocampi were lower in the

patients compared to controls (p = 0.05 and p < 0.003, respectively), "

Dr. Emad's team explains. " Another statistically significant

difference was observed in choline levels in the right hippocampus,

which were higher in the patient group. " Patients also had

significantly lower NAA/choline and NAA/creatine ratios compared to

controls.

There were no differences between groups in other measured metabolites

or in the choline/creatine ratio.

In the patient group, language scores were significantly correlated

with choline and creatine levels (p = 0.041 and p = 0.006,

respectively), but there was no significant correlation between

metabolites or their ratios and numbers of tender points, Fibromyalgia

Impact Questionnaire score, or pain as assessed by the visual analog

scores.

" The hippocampus was dysfunctional in patients with fibromyalgia, as

shown by lower NAA levels..., representing neuronal or axonal

metabolic dysfunction, " the investigators conclude. " As the

hippocampus plays crucial roles in maintenance of cognitive functions,

sleep regulation, and pain perception, we suggest that metabolic

dysfunction of hippocampus may be implicated in the appearance of

these symptoms associated with this puzzling syndrome.

J Rheumatol 2008;35:1371-1377.

http://www.medscape.com/viewarticle/579783

--

Not an MD