Understanding pain and mental illness Impact on management principles

Transcription

1 Understanding pain and mental illness Impact on management principles Chris Alderman Consultant Psychopharmacologist

2 Pain and mental illness - context PAIN MENTAL ILLNESS OTHER FACTORS (personality, history. context)

3 Aspects of Pain and Mental Illness: Both can take many forms More than one manifestation of either or both can be present at the same time Both can be acute or chronic Significant interplay between the two

4 Pain and Mental Illness: A complicated relationship Often comorbid One may precede the other, or both arise at once Treatment for one can complicate the other Treatments for either can interact Adversely Beneficially

5 Pain some basics What is pain? An unpleasant sensory and emotional experience associated with actual or potential tissue damage Pain is whatever the experiencing person says it is. May not be directly proportional tissue injury Highly subjective

6 Describing pain only in terms of its intensity is like describing music only in terms of its loudness

7 PAIN HISTORY Description: severity, quality, location, temporal features, frequency, aggravating & alleviating factors Previous history Context: social, cultural, emotional, spiritual factors Meaning Interventions: what has been tried?

8 Types of Pain Can be classified by physiology: Nociceptive pain (stimuli from somatic and visceral structures) Neuropathic pain (stimuli abnormally processed by the nervous system) Both types can be present simultaneously

9 How does nociceptive pain happen? Nerve endings can differentiate between noxious and innocuous stimulus Stimulus can be: Mechanical (incision or tumor growth) Thermal (burn) Chemical (toxic substance) Tissue damage accompanied by release of various by the damaged tissue movement of pain impulse to the spinal cord.

10 Substances released The substances released from the traumatized tissue include but are not limited to: prostaglandins bradykinin serotonin substance P histamine Create nerve impulse

11 Transmission of pain impulses Impulse à spinal cord à brain à pain processed Neurotransmitters help convey the impulse from the spinal cord to the brain

12 Perception and modulation of pain Pain perception probably occurs in the cortical structures Modulation happens after other impulses from the brainà spinal cord Descending fibers release substances that can reduce transmission of noxious stimuli. Helps explain wide variations of pain among people.

13 Neuropathic Pain Abnormal processing of the impulses either by the peripheral or central nervous system Many underlying causes injury (amputation and subsequent phantom limb pain) scar tissue from surgery nerve entrapment (carpal tunnel) Nerve damage (diabetic neuropathy) Can occur in absence of enduring pathology

14 Pain terminology Acute pain: lasts less than six months, subsides once the healing process is over Chronic pain: Involves complex processes Often associated with altered anatomy and neural pathways Constant and prolonged, lasting longer than six months

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16 Chronic Pain Syndrome Pain can become the primary focus of life Relationships altered Sometimes arise from acute, unrelieved pain e.g. multiple trauma, phantom limb pain after amputation, repeated back surgery Sometimes from neuro-muscular disorders such as fibromyalgia, rheumatoid arthritis, multiple sclerosis

17 Chronic Pain Sometimes unwelcome in the doctor s surgery or emergency departments - very complex, time consuming, no easy answers or quick fixes Behavioral medicine may help - learning different coping mechanisms, biofeedback, non-opioid interventions

18 Mental illness and the complexity of the brain 100 billion neurons in the cerebral cortex alone (more than the stars in the Milky Way) Additional trillion neurons in cerebellum 1,000 10,000 dendrites, spines and synapses per neuron, + feedback loops

19 Consequences of mental illness Enormous suffering Stigma Social isolation and withdrawal Occupational disability Markedly increased health service utilisation Comorbid substance use disorders and sequelae of these

20 Consequences of mental illness Poor physical health Child abuse and neglect Relationship and family difficulties Treatment and hospitalisation costs Medicines expenditure Self-injurious behaviour (SIB) Suicide risk

21 10 Leading Causes of Disability in the World (WHO) Unipolar Depression Iron-deficiency Anemia Falls Alcohol Use COPD Bipolar disorder Congenital anomalies Osteoarthritis Schizophrenia Obsessive-compulsive disorder 10.7%

22 Australian National Survey of Mental Health & Wellbeing of Adults 18% of the survey cohort affected by one of the mental illnesses in preceding 12/12 Higher incidence amongst younger (18-24) 27% Lower incidence amongst older (> 65) 6.1% Anxiety disorders (12 vs 7.1%) and depression (7.4 vs 4.2%) more prevalent for women Substance use disorders more common for men (11 vs 4.5%)

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24 Psychotropic pharmacoepidemiology Australian National health Survey: 26,000 households relating to preceding 2/52 19% of adults reported use of medication (either prescribed medication and/or vitamins, minerals or herbal treatments) for their mental wellbeing Of these 27% reported using antidepressants, 23% used sleeping tablets and 10% said that they had used medications for anxiety or nerves

25 Pain and mental illness - context PAIN MENTAL ILLNESS OTHER FACTORS (personality, history. context)

26 Medications in general All medicines are poisons, it just depends on the dose Not all medicines are prescription medicines Not all medicines have scientific proof to back them All medicines have side effects Most medicines can interact with other medicines

27 Medications in general Medicines influence the person, the person influences the medicine People don t necessarily take medicines as they are intended to be taken Some people become confused about medicines Not all medicines work for everyone who takes them

28 Medications for pain Various different types of analgesia pain killers Medicines used to manage symptoms associated with pain Medicines used to manage the side effects associated with pain medicines Interactions with other medicines used for other purposes

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30 Treatment for pain Non-drug approaches alternative or adjuvants to pharmacotherapy: Heat, cooling Exercise Behavioural approaches Mindfulness and meditation Physiotherapy Therapeutic massage Acupuncture TENS

31 Simple analgesia Topical treatments Counter-irritants Anti-inflammatory products Paracetamol Not entirely harmless Can be hugely beneficial Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) Very commonly used (Nurofen, Celebrex, Voltaren, Mobic) Effective but can cause serious side effects» GI, asthma, kidneys, bleeding risk, drug interactions

32 Step Two: Opioids and Adjuvants Mild-moderate opioids Codeine Buprenorphine Dextropropoxyphene Can be used in combination with simple agents Range of predictable adverse effects Sedation Respiratory suppression Constipation Nausea

33 Adjuvant medicines Antidepressants SSRIs TCAs Others Anticonvulsants Carbamazepine Pregabalin and gabapentin Local anaesthetics Sedatives Others (e.g.? Cannabinoids)

34 Powerful Opioids No longer referred to as narcotics Many examples: Morphine Oxycodone Methadone Tramadol Predictable pattern of adverse effects Additional concerns regarding dependence, tolerance and diversion

35 Mental illness and rehabilitation PAIN Effects on relationships OTHER FACTORS (personality, history. context) Side effects of drugs Comorbid mental illness Existential despair Substance abuse & diversion Disability Coping strategies

36 Mental illness, pain and rehabilitation: The Big Five Affective disorders Depression BPAD Adjustment disorders Somatoform disorders Anxiety disorders PTSD Panic disorder Substance use disorders EtOH Illlicit drugs Prescription drugs Personality disorders

37 Psychotropic drugs Antidepressants SSRIs SNRIs TCAs Others Anticonvulsants Carbamazepine Pregabalin and gabapentin

38 Psychotropic drugs Antipsychotics Anxiolytics Hypnosedatives Mood stabilisers Medications for substance use

39 Psychotropic drugs it s complicated What is a mental illness, what is a personality trait, what is a normal human reaction to pain, suffering and possible ill-treatment by authority figures? Grief and loss Influence of upbringing Belief systems Conventional medicine Alternative medicines Concepts of strength, coping and self-efficacy

40 I didn t see that coming (part one) Immediate side effects of drugs Constipation Nausea Sexual dysfunction Sleep disturbances Latent side effects of drugs Weight gain, metabolic side effects Hormonal changes Anaemia Respiratory depression

41 I didn t see that coming (part two) Effects of drugs on fitness to drive Adverse impact of weight gain upon exercise capability Significant weight gain bones, joints and spine Effects on dentition Cognitive impairment Polypharmacy and drug interactions

42 I didn t see that coming (part three) Effective treatment of pain can have a (very) positive impact upon the course of mental illness Effective treatment of a mental illness can have a (very) positive impact upon pain Medication is not always forever Medication is sometimes forever Either way, functional recovery is possible

43 Thanks for your attention questions?