Fibromyalgia

Introduction

Fibromyalgia is a chronic, complex disorder characterized by widespread musculoskeletal pain, heightened pain sensitivity, fatigue, cognitive disturbances, and a range of somatic symptoms. It is recognized as a central sensitization syndrome, meaning that the nervous system amplifies pain signals. The condition affects people of all ages but is more prevalent in women, particularly between the ages of 30 and 50. Although the exact cause is unknown, research points to a combination of genetic predisposition, environmental triggers, and neurochemical imbalances.

---

Epidemiology

• Prevalence: Estimated to affect 2–4% of the population globally.

• Gender: Women are more frequently diagnosed than men, with a ratio of approximately 3:1 to 9:1 depending on the population studied.

• Onset: Can occur at any age but is most often diagnosed in middle adulthood.

• Comorbidities: Frequently associated with irritable bowel syndrome (IBS), chronic fatigue syndrome (CFS), temporomandibular joint disorder (TMJD), migraines, depression, and anxiety.

---

Etiology and Pathophysiology

The etiology is multifactorial, involving:

1. Central Sensitization – An exaggerated response of the central nervous system to normal sensory input.

2. Neurotransmitter Imbalances – Alterations in serotonin, norepinephrine, and dopamine affecting pain perception.

3. Hypothalamic–Pituitary–Adrenal (HPA) Axis Dysregulation – Abnormal stress response impacting sleep, mood, and pain.

4. Autonomic Nervous System Dysfunction – Leading to symptoms such as dizziness, orthostatic intolerance, and temperature dysregulation.

5. Genetic Susceptibility – Family clustering suggests a hereditary component.

6. Environmental Triggers – Physical trauma, infections, or significant emotional stress can precede onset.

---

Risk Factors

• Family history of fibromyalgia or chronic pain disorders

• Autoimmune diseases such as rheumatoid arthritis or lupus

• Physical or emotional trauma

• Chronic stress

• Female gender

• Sleep disturbances

---

Clinical Features

Primary Symptoms

1. Widespread Musculoskeletal Pain – Persistent and diffuse, affecting both sides of the body and above and below the waist.

2. Fatigue – Often profound and disproportionate to activity levels.

3. Sleep Disturbances – Non-restorative sleep, frequent awakenings, and disorders like restless legs syndrome.

4. Cognitive Dysfunction (“Fibro Fog”) – Difficulty with memory, attention, and multitasking.

Associated Symptoms

• Headaches or migraines

• Irritable bowel symptoms

• Depression and anxiety

• Numbness or tingling in extremities

• Temporomandibular joint pain

• Sensitivity to temperature, noise, and light

• Urinary frequency or urgency

---

Diagnostic Criteria

The 2016 Revised American College of Rheumatology (ACR) Criteria include:

1. Widespread Pain Index (WPI) ≥ 7 and Symptom Severity Scale (SSS) score ≥ 5
   or WPI 4–6 and SSS score ≥ 9.

2. Symptoms present at a similar level for at least 3 months.

3. Absence of another disorder that would otherwise explain the pain.

---

Differential Diagnosis

• Rheumatoid arthritis

• Systemic lupus erythematosus

• Polymyalgia rheumatica

• Hypothyroidism

• Multiple sclerosis

• Myopathies

• Chronic fatigue syndrome

---

Management

Fibromyalgia requires a multimodal approach that integrates pharmacological, non-pharmacological, and lifestyle interventions. The goal is symptom control and functional improvement rather than cure.

---

Pharmacological Treatment

While no single drug cures fibromyalgia, certain medications target specific symptoms.

1. Neuromodulators (First-line)

• Duloxetine – An SNRI that modulates pain pathways and improves mood.

  • Dose: Start at 30 mg once daily, increase to 60 mg once daily as tolerated.

• Milnacipran – Another SNRI approved in some countries for fibromyalgia.

  • Dose: Start at 12.5 mg once daily, titrate to 50 mg twice daily.

• Pregabalin – Alpha-2-delta ligand that reduces neuronal excitability.

  • Dose: Start at 75 mg twice daily, may increase to 300–450 mg/day.

2. Tricyclic Antidepressants (TCAs)

• Amitriptyline – Improves sleep quality and pain.

  • Dose: 10–25 mg at bedtime; may increase to 50 mg as needed.

• Nortriptyline – Alternative with fewer anticholinergic effects.

  • Dose: 10–25 mg at bedtime.

3. Muscle Relaxants

• Cyclobenzaprine – Structurally related to TCAs, promotes restorative sleep.

  • Dose: 5–10 mg at bedtime.

4. Analgesics

• Acetaminophen – For mild pain relief.

  • Dose: 500–1000 mg every 4–6 hours, max 3–4 g/day.

• Tramadol – Weak opioid with serotonin–norepinephrine reuptake inhibition.

  • Dose: 50–100 mg every 4–6 hours as needed, max 400 mg/day.

• NSAIDs have limited benefit for widespread pain but may be used for comorbid inflammatory conditions.

5. Other Agents

• Gabapentin – Similar to pregabalin, useful for neuropathic pain.

  • Dose: 300 mg at bedtime, titrate to 900–2400 mg/day.

---

Non-Pharmacological Treatment

Equally important as medications, these strategies aim to address physical conditioning, psychological resilience, and lifestyle balance.

Exercise Therapy

• Low-impact aerobic activities: walking, swimming, cycling.

• Start slow, gradually increasing duration and intensity.

• Stretching and flexibility training to reduce stiffness.

Cognitive Behavioral Therapy (CBT)

• Helps modify negative thought patterns and coping strategies.

• Reduces anxiety and depression associated with chronic pain.

Sleep Hygiene

• Regular sleep–wake schedule.

• Avoid caffeine and electronics before bedtime.

• Create a dark, quiet sleep environment.

Physical Therapies

• Hydrotherapy, massage, and gentle stretching.

• Posture correction and ergonomic advice.

Mind–Body Approaches

• Yoga, tai chi, and mindfulness meditation.

• Deep-breathing exercises to reduce sympathetic overactivity.

---

Prognosis

Fibromyalgia is chronic but non-degenerative. With comprehensive treatment, many patients experience symptom reduction and improved function. However, relapses may occur with stress, illness, or lifestyle disruption.

---

Complications

• Reduced quality of life

• Increased absenteeism from work

• Risk of depression or anxiety disorders

• Social withdrawal and isolation

---

Patient Education and Self-Management

• Understanding that fibromyalgia is a real, neurobiological condition.

• Setting realistic goals for activity and pain control.

• Engaging in regular physical activity despite discomfort.

• Recognizing triggers and developing strategies to manage flare-ups.