Mediterranean Diet and Disease Activity in Axial Spondyloarthritis Receiving Biologic Therapy

This study aims to evaluate the effect of the Mediterranean diet on disease activity, quality of life, inflammation, pain, and treatment response in patients with axial spondyloarthritis (ankylosing spondylitis) who are receiving stable biologic therapy. Axial spondyloarthritis is a chronic inflammatory disease that affects the spine and sacroiliac joints, often leading to pain, stiffness, and reduced quality of life. While biologic disease-modifying antirheumatic drugs (bDMARDs) are effective in reducing inflammation, lifestyle factors such as diet may also play an important role in disease outcomes. In this randomized controlled trial, a total of 110 patients diagnosed with ankylosing spondylitis will be enrolled. Participants will be randomly assigned to either the Mediterranean diet group or the control group. The Mediterranean diet group will receive a structured diet program supervised by a dietitian, while the control group will continue their standard care with general healthy eating advice. Patients will be monitored for dietary adherence, and assessments will be conducted at baseline and after 3 months. The primary outcome measure is the change in Ankylosing Spondylitis Disease Activity Score with C-reactive protein (ASDAS-CRP). Secondary outcomes include BASDAI, BASFI, BASMI, laboratory markers of inflammation, quality of life (SF-36), fatigue (FACIT-Fatigue), sleep quality (PSQI), anxiety and depression (HADS), medication adherence (MMAS-8), and Mediterranean diet adherence (PREDIMED). The study will provide valuable data on whether a Mediterranean diet can improve clinical outcomes and support the management of axial spondyloarthritis in patients receiving biologic therapy, potentially contributing to future lifestyle-based treatment strategies.