Increased Psychosocial Stress Abstract

We continue to share research abstracts with our readers from the American College of Rheumatology 2012 Meeting for the next few newsletters.  

A summary of an entire scientific study, an abstract is usually published at the beginning of a peer-reviewed paper in journals or in the case of medical meetings, in abstract books and on large poster boards displayed at a conference.  They are selected in the same way as submitted manuscripts for publication.  A peer-review committee evaluates and grades the submitted research study using an objective scale.  The highest ranking abstracts are selected for poster presentation for the meeting, and in some cases, the author is invited to make a “podium” presentation during the meeting.  While posters are on display at the meeting, the author(s) stands by his/her work to answer questions and educate other professionals about the study findings so as to promote new ways of thinking and new research ideas.

Following is an abstract about psychosocial stress as a component of triggers in the development of fibromyalgia symptoms.

Continue here from February 2013 FM-CP Advocate Newsletter

Increased Psychosocial Stress is a Major Component of Fibromyalgia Triggers
Emma K. Guymer, Kathleen Elford and Geoffery O. Littlejohn

Purpose: The first fibromyalgia symptoms that develop in a fibromyalgia patient are known to occur under conditions unique to each person.  Although both psychological and physical triggers are recognized as fibromyalgia instigators their frequency and contribution to illness is less defined.  The purpose of this Australian study was to examine fibromyalgia triggers and identify clinical features linked to specific triggering situations.

Method: 260 patients seen in a public outpatient clinic were questioned using a standardized interview about the how their symptoms started.  The Widespread Pain Index (WPI ), Symptoms Severity Score (SSS) and the Fibromyalgia Impact Questionnaire (FIQ) were all used to collect data.  The patients were divided into groups based on whether or not they reported a trigger for their fibromyalgia, and if this involved increased levels of psychosocial stress, physical illness or injury.  These groups were then compared for differences regarding clinical and demographic features.

Results: Information collected from the patients broke down to 232 (89.2%) reporting a specific triggering situation corresponding to the onset of their symptoms.  77 (29.7%) described a triggering situation of purely increased psychosocial stress and a further 107 (41.3%) described a purely physical trigger.  Patients with a trigger involving increased psychosocial stress had a higher number of coexisting fibromyalgia-associated conditions (e.g. irritable bowel syndrome, temporomandibular joint disorder, etc) (p<0.0005), higher levels of anxiety (p<0.05) and depression (p<0.05) than those patients who did not.  If patients who had a psychosocial stress component of their trigger were currently regularly exercising, they had significantly lower FIQ scores (p<0.05>, better physical function (p<0.05), less reported pain (p<0.05), less sleep disturbance (p<0.05), fewer positive tender points (p<0.05), and lower WPI (p<0.05) and SSS (p<0.05), than those patients who were not regularly exercising.  Patients without a trigger involving increased psychosocial stress who were regularly exercising had lower FIQ scores (p<0.05) and less anxiety (p<0.05) only.  If patients with psychosocial stress triggers were currently using medications with proven benefit in fibromyalgia (amitriptylne, duloxetine or pregabalin), they had better reported physical function (p<0.05) than those patients not using these medications.  There was no significant clinical difference found between those using pain management psychology and those who were not, in the group of patients who had reported increased psychosocial stress as part of their trigger.

Conclusion: The study revealed that most of the patients reported a specific trigger for their fibromyalgia.  The majority of these involved increased levels of psychosocial stress including those with injury or illness.  Patients with an increased psychosocial stress component to their trigger had less severe clinical features if they regularly exercised.

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Another interesting abstract at the ACR meeting concerned genomics in fatigue in people with FM.  Genomic is the adjective for genome (a full set of chromosomes; all of the inheritable traits of an organism).  It appears there are two different patterns of gene expression in these patients.  Read the full abstract for more information.  

Genomic Categories of Fatigue in Women with Fibromyalgia
Nada Lukkahatai, Brian T. Walitt, Majors Benjamin, et al

Background/Purpose:  FM is the chronic experience of body-wide pain, fatigue cognitive dysfunction, and disordered sleep that occurs in the absence of any clear cause.  Fatigue is a cause of significant morbidity and disability in FM.  Most genomic studies in the FM population focus on pain symptoms.  Only a few studies had investigated the fatigue experience in FM and no genomic studies investigated FM-specific fatigue symptoms.

The purpose of this study is to identify genomic categories of fatigue in fibromyalgia (FM) and describe behavioral characteristics of these fatigue categories.

Methods: Under an active Medstar Research institute protocol, FM participants diagnosed by 2010 diagnostic criteria and pain-free, race, age and gender –matched controls were enrolled in the study.  Participants completed questionnaires.  RNA from peripheral blood samples collected using Paxgene tubes® were analyzed for differential gene expression using microarray technology with Affymetrix GeneChip® human genome U133 Plus 2.0.  Cluster analysis was used to determine genotypic categories.  The differences of symptoms between two clusters were analyzed by the analysis of variance (ANOVA).

Results:  Thirty one Caucasian women diagnosed with FM, experiencing significant fatigue (MFI-general fatigue > 13) and 20 pain and fatigue free, age-, race-, gender-matched controls were enrolled.  Microarray data showed differential upregulated expression of centromere protein K (CENPK) gene after the probesets passed filtering criteria of 1% false discovery rate (FDR) and a slope of >log2 (over 2.0-fold change, p<0.05).

This CENPK gene is related to centromere function.  Cluster analysis was conducted on the xpressed genes from FM subjects which revealed two distinct clusters.  Forty nine genes were differentially expressed over 2-fold change (p = 0.027).  Genes that upregulated in the high pain interference and high depression cluster include genes related to immune response , iron absorption and GABA transport.  Genes related to calcium iron binding were differentially expressed in the other FM cluster with lower pain interference and depression.

Conclusion:  Within FM women with high fatigue, there appear to be two distinct patterns of gene expression. These genomic patterns correspond with differences in behavioral characteristics.  Further investigation of these genomic patterns may provide some insights into the mechanisms behind the relationship of fatigue with other FM behavioral symptoms.