Introduction

• Chronic pain: unpleasant sensory and emotional experience associated with actual or potential tissue damage

  • It is the main reason why people seek medical care

  • Higher prevalence rates for women, people from low socioeconomic background, military veterans, and people residing in rural areas

    • Racial + ethnic minorities: due to enhanced physiological pain sensitivity, cultural differences, and reduced access to care

• The economic costs of chronic pain are substantial

Chronic pain as a disease model

• Acute pain: in response to tissue trauma, has a survival value and plays a role in healing

• Pain becomes pathological when it persists beyond the expected healing period (3 months)

• Chronic pain = disease

  • Alterations in the PNS and CNS + quality of life decrements

• Factors promoting resiliency can promote healing and reduce pain chronification

Biopsychosocial model and consequences of chronic pain

• Biopsychosocial model: pain and disability are multi-dimensional. They are dynamic interactions among biological, psychological, and social factors that reciprocally influence each other

• Chronic pain effects

  • Interferes with someone’s ability to work and can lead to financial ramifications, including homelessness

  • Affects relationships and self-esteem

  • Reduces life expectancy

  • Deleterious pathophysiological and anatomical changes

  • Suppression of cell-mediated immunity and humoral immunity

  • Alterations in gene expression

  • Decreases in grey brain matter

• Pain might affect the survival rate of patients with cancer

Classification of pain and its importance

• Pain is always subjective

  • A patient’s report of pain should be accepted at face value in absence of evidence to the contrary

• 3 main categories of chronic pain:

  • Nociceptive

    • Results from activity in neural pathways

    • Most common

  • Neuropathic

    • Caused by damage or disease affecting the somatosensory nervous system

    • It is maladaptive

    • Associated with greater decrements in quality of life

  • Nociplastic

    • Arises from the abnormal processing of pain signals without any clear evidence of tissue damage of discrete pathology involving the somatosensory system

    • Augmented sensory processing + diminished inhibitory pathways

Mixed pain and pain classification as a continuum

• Many pain conditions have a mixed pain phenotype

• Types of pain occupy different points on a continuum

• There is no reason cancer and non-cancer patients should be treated differently

  • In patients who have recovered from cancer and have chronic pain, treatments should be similar to other patients, tailored to unique consideration

Pain management

Best practices

• Mechanism-based pain treatment = optimal but difficult

• Treatment is typically symptom-based or disease-based

• Goals of therapy: tailored towards an improved quality of life

• Interdisciplinary treatment: uses a personalized approach and a shared-decision model

• Multimodal approach: includes self-care, a healthy lifestyle, and ergonomic modifications

Exercise and psychotherapy

• Exercise: excellent self-management strategy

• CBT