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