What is the best management approach for a patient with intermittent back and hip stiffness that improves with activity, on aspirin, statin, and amlodipine, with elevated tryptase levels?

Inflammatory Back Pain: Likely Axial Spondyloarthritis

This presentation of morning stiffness in the back and hips that improves with activity is classic for inflammatory back pain, most likely axial spondyloarthritis (axSpA), and the elevated tryptase is a separate finding that requires monitoring but should not alter your primary rheumatologic management approach.

Primary Diagnosis and Initial Management

The pattern of stiffness resolving with activity is pathognomonic for inflammatory rather than mechanical back pain 1. You should initiate continuous NSAIDs as first-line therapy immediately 1. The ASAS/EULAR guidelines strongly recommend NSAIDs as first-line treatment for patients with inflammatory back pain, with continuous treatment preferred over on-demand dosing for persistently active disease 1.

NSAID Selection Considerations

• Start with a continuous NSAID regimen rather than as-needed dosing, as continuous therapy is superior for symptom control in inflammatory conditions 1
• Consider cardiovascular, gastrointestinal, and renal risks when selecting the specific NSAID, particularly given this patient is already on aspirin and amlodipine 1
• Monitor for drug interactions between NSAIDs and the existing cardiovascular medications 1

Exercise Therapy: Essential Component

Strongly recommend enrollment in a structured exercise program immediately 1. This is not optional—exercise therapy is a Class I recommendation for inflammatory back and hip conditions 1.

Specific Exercise Prescription

• Cardiovascular and resistance land-based exercise should be the foundation 1
• Aquatic exercise can be added based on patient preference and access 1
• Minimum frequency: 3 sessions per week, 30 minutes per session, for at least 12 weeks 1
• The exercise should be supervised initially, with transition to a home program with structured monitoring 1

Addressing the Elevated Tryptase

The elevated tryptase is likely incidental but requires consideration:

• Obtain baseline creatine kinase (CK) levels immediately to distinguish potential statin-induced myopathy from the inflammatory condition 2
• Check thyroid-stimulating hormone (TSH), as hypothyroidism can cause both muscle symptoms and exacerbate statin-related issues 2
• Measure baseline ALT/AST given the patient is on atorvastatin 2

Statin Management in This Context

Continue the statin unless CK is >10 times upper limit of normal with muscle symptoms 2. The American College of Cardiology recommends:

• If CK is 3-10 times ULN with symptoms: monitor weekly and follow symptoms closely 2
• If CK >10 times ULN with symptoms: discontinue immediately 2
• Normal or minimally elevated CK does not rule out statin-related symptoms and should not dismiss the patient's complaints 2

Cardiovascular Medication Optimization

Given the patient is on aspirin, statin, and amlodipine:

• Continue high-dose statin therapy as indicated for cardiovascular risk reduction (Class IA recommendation) 1
• The aspirin should be continued for cardiovascular protection 1
• Ensure blood pressure is adequately controlled with the amlodipine 1

Critical Pitfalls to Avoid

Do not treat this as mechanical back pain or osteoarthritis—the improvement with activity distinguishes inflammatory from degenerative conditions 1. Key errors to avoid:

• Never recommend spinal manipulation with high-velocity thrusts if there is any evidence of spinal fusion or advanced osteoporosis, as this carries risk of fracture and spinal cord injury 1
• Do not delay NSAID therapy while waiting for imaging or specialist referral 1
• Do not prescribe exercise "as tolerated"—specific frequency and duration parameters improve outcomes 1

Monitoring and Follow-up

• Reassess at 2,4,8, and 16 weeks after initiating therapy 3
• Monitor CK if any new muscle symptoms develop 2
• Repeat spinal imaging should not occur more frequently than every 2 years unless clinically indicated 1
• Track patient-reported outcomes including pain intensity, disability level, and quality of life 1

When to Escalate Therapy

If symptoms persist after 3 months of optimal medical therapy (continuous NSAIDs) and structured exercise:

• Assess disease-specific quality of life to determine if biologic therapy is warranted 1
• Consider referral to rheumatology for potential TNF inhibitor therapy if NSAIDs and exercise fail 1
• The elevated tryptase should not preclude biologic therapy if otherwise indicated 1