Perception of pain The message is received by the brain and pain is perceived because of the way, the brain works in individuals. Perception of Pain
Suffering Negative and emotional reactions caused by pain depression fear anxiety stress etc Suffering
Pain behaviours Saying” Ouch!!” Grimacing Limping Lying down Recourse to health care Refusing work Pain behaviours
The purpose of our research The clarification of the process from pain perception to suffering through researching patients with schizophrenia and chronic pain.
Why patients with schizophrenia? They are less sensitive to pain ruptured appendix perforated bowels peritonitis painless myocardial infarction Chronic pain is rare. ? ? ?
Why are they less sensitive? Cognitive impairment Affective impairment Attention deficiency
Why patients with schizophrenia? Pain Suffering Pain Behaviour Patients with chronic painPatients with schizophrenia
Degree of pain suffering Strong Weak Schizophrenia Normal Chronic pain Schizophrenia is a human model considered to be the opposite of that with chronic pain.
Methods Chieko Takamura Chieko was an artist who created many works of art after suffering with schizophrenia.
Participants Patients with schizophrenia: - Diagnosed using DSM-IV criteria - Exclusion criteria 1) cannot understand the test 2) cannot answer the questionnaire accurately Healthy control: - Not diagnosed with any psychiatric illnesses
Clinical assessments of patients Symptoms of schizophrenia - Positive and Negative Syndrome Scale (PANSS) Medication - Chlorpromazine equivalents History patient’s age on diagnosis diabetes self injury etc.
The phenotype Patients Control The data showed potential phenotype groups in schizophrenia.
Analgesic effect of antipsychotics? Dopamine D2 antagonist (traditional Antipsychotics) and opioids Neuroleptic analgesia Less sensitivity to pain due to antipsychotics’ analgesic effects? Not dosage dependent
Severe schizophrenia? Less sensitivity to pain due to the symptoms of schizophrenia? No correlation between symptoms and pain sensitivity No correlation between symptoms and pain sensitivity shown in PANSS (schizophrenia syndrome scale) data.
Schizophrenia Normal HPT and pain suffering Strong Weak Schizophrenia Normal Chronic pain Degree of pain suffering Heat pain threshold High Low Patients with normal heat pain thresholds have a normal degree of suffering? ?
Patient 1: Confident against pain!! History of spinal contusion injury(SCI) No pain No analgesics HighLow Heat pain threshold
Patient 2: Always feels knee pain Feels pain due to osteoarthritis in the knee. Receives general therapy for knee pain HighLow Heat pain threshold
Patient 3: Feels pain but ・・・・ ・ History of SCI with paralysis She feel pain. She looks free from pain HighLow Heat pain threshold
Schizophrenia Normal HPT and pain suffering Strong Weak Schizophrenia Normal Chronic pain Degree of pain suffering Heat pain threshold High Low
Why don’t need analgesics? The last patient felt pain. She didn’t want her pain treated. Pain is an unpleasant sensory and emotional experience Her pain probably was not so unpleasant to require treatment.
Schizophrenia less sensitive to pain 1. Sensory insensitivity 2. Less suffering due to the noxious stimuli ? ?? ? ?
Future plans (1, 2, 3 ・・・・ ) John Forbes Nash, Jr. is an American mathematician who received a Novel Prize for his works in game theory. Nash is the subject of the Hollywood movie “A Beautiful Mind”. The film focuses on Nash's mathematical genius and his struggle with schizophrenia.
2. fMRI study Participants Patients with schizophrenia not suffering from pain and Controls Pain task 15˚C, 45˚C, 50˚C stimulation lasting 20s Analyzing the areas which contribute to suffering
3. Other possible imaging studies Dopamine Glutamate
Significance : Area detection Area detection Evaluation of degree and treatment Molecular mechanism Direct stimulation therapy
Significance : Genes Target gene Molecular mechanism New analgesic and anesthetic Progress in schizophrenia research
Acknowledgements Department of Psychiatry Ryota Hashimoto and his colleagues Nihon Koden Cooporation Syogo Maeda & Tomoko Oku Department of Pain Medicine Masahiko Shibata Graduate School of Dentistry Syoichi Ishigaki Department of Anesthesiology All my colleagues