Past Pain Experience and Perception of Experimental Pain
Condition: Schizophrenia; Major Depression
MeSH terms: Depression; Schizophrenia; Depressive Disorder, Major
Study type: Observational

Summary: 
      Differences in pain perception between subjects with and without psychiatric illness may be
      influenced by the individual experience, and not primarily by the pathology, although the
      pathological frame may amplify it.The aim of this study is to establish if the
      characteristics of experimental pain feeling are influenced by the past pain experience,
      anxiety and emotion, independently from the diagnosis. The pain experience will be evaluated
      by an inventory of the potentially painful situations that one can come across through the
      life, to determine the following points : Number of painful events in the past, number of
      painful points during the last 6 months, number of painful events lasting more than 6 months,
      sum of pain intensities (graduated with Visual Analogic Scale VAS from 0 to 10), sum of
      gravity (evaluated from 0 to 5), the category of pain experience qualification (mostly
      affective, mostly sensorial, or both).

      Schizophrenic, depressed and control participants will be recruited, and their pain
      experience throughout life will be put it in relation to experimental pain tests results
      (pressure application, ischemia induction), anxiety and emotion (Hospital Anxiety and
      Depression scale HAD), catastrophizing (Pain Catastrophizing Scale PCS), Heart Rate (HR)
      variation, Blood Pressure (BP) variation.
    

Detailed description: 
      The perception of moderated experimental pain (about 3 out of ten with visual analogue scale
      VAS) in subjects with schizophrenia (Girard et coll., 2011), major depression (ED) (bipolar
      or isolated/recurrent episode) (to be published) in comparison with controls without
      psychiatric pathologies show that exploration of pain in situation like medical examination
      to identify painful points should be done in the same conditions for persons with psychiatric
      troubles and persons without mental disease. But the risk is that the expression of pain,
      either in experimental conditions nor in the daily life, is not in relation with the feeling
      or perception of pain. Numerous factors may interfere in the pain message modulation, like
      the past pain experience, stress and anxiety, which are not or partially explored in
      experimental studies. The individual experience of pain is constructed throughout the whole
      life, from several influences (biological, psychological, and sociocultural). The symptoms
      interfaces of the different psychiatric troubles seem to be widely involved in the pain
      process, and its progressive construction. This study aims to better understand the
      relationships between all those variables.

      Procedures applied :

      Anterior pain experience evaluation (questionnaire); Pain tests : 160 kPa pressure
      application to determine corresponding pain with VAS), and ischemia induction to determine
      the time necessary to obtain a pain equivalent to 3 out of 10; anxiety and emotional
      evaluation (Hospital Anxiety and Depression scale), catastrophizing evaluation (Pain
      Catastrophizing Scale), HR variation and BP variation (vegetative measures linked to anxiety)
      collection of diagnosis, and therapeutic treatment
    

Intervention name(s): experimental pain tests
Intervention type(s): Other
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Subjects hospitalized in the Esquirol Hospital center with schizophrenia or major
        depression according to the DSM-IV-TR criteria.

        Subjects without without known psychiatric history. Recruited persons will be matched
        according to age classes.
      
Keywords: Schizophrenia; Major depression; Pain; Past pain experience