Chronic Pain Definition and Management

Introduction to Chronic Pain

The International Association for the Study of Pain defines chronic pain as pain persisting for 3 months or longer beyond normal tissue healing time, a definition endorsed by multiple major guideline societies, including the American Heart Association and the American College of Physicians 1, 2, 3, 4, 5
The 3-month threshold is the most widely accepted standard across guidelines from the American Heart Association, HIVMA/IDSA, American College of Physicians, and International Association for the Study of Pain 1, 2, 3, 4
The American Geriatrics Society notes that "persistent pain" is the preferred terminology over "chronic pain" to avoid negative stereotypes, though both terms are used interchangeably in medical literature 6

Chronic pain persists beyond the expected period of tissue injury and repair, representing either ongoing injury or upregulation of the sensory system independent of active tissue damage 2, 4
Chronic pain is characterized by functional and structural changes (neuroplasticity) in the central nervous system at every level, distinguishing it from acute pain 2, 4
Chronic pain negatively affects an individual's wellbeing and is multifactorial in nature, involving biological, psychological, and social components 1

Management requires identifying the pain mechanism (nociceptive, neuropathic, or centralized/mixed) and matching treatment to the specific pathophysiology, while simultaneously addressing psychosocial factors through a biopsychosocial approach 2, 4, 7
The American College of Physicians recommends first-line pharmacotherapy for nociceptive pain, including NSAIDs and acetaminophen 8, 7
The American College of Physicians recommends first-line pharmacotherapy for neuropathic pain, including duloxetine, venlafaxine, gabapentin, pregabalin, or topical lidocaine 8, 7
The FDA-approved first-line treatments for centralized pain/central sensitization include pregabalin, duloxetine, or milnacipran 8, 7

Cognitive behavioral therapy (CBT) is essential to address pain catastrophizing, develop coping strategies, and manage comorbid depression/anxiety 7
Regular physical activity tailored to patient capabilities improves pain through multiple mechanisms, including reduced inflammation, improved cardiovascular fitness, angiogenesis, and mitochondrial function 1, 7
Exercise therapy for conditions like peripheral artery disease shows that only 5-30% of pain improvement correlates with hemodynamic changes, indicating systemic adaptation mechanisms 1

Screen for and treat comorbid depression, anxiety, sleep disturbance, and fatigue, which commonly accompany chronic pain and influence treatment outcomes 2, 7

Do not focus solely on pharmacological management, as this approach fails to address physical function and psychological factors critical to outcomes 7
Do not assume pain intensity alone guides treatment, as functional status, quality of life, and psychosocial factors are equally important outcomes 1