A Randomized, Double-blind Clinical Trial on the Efficacy of a Dietary Formulation Containing Medium-chain Triglycerides (MCT) and Fiber in Patients With Psoriatic Arthritis

Inclusion Criteria:

• Adult patients: aged 18-80 years;

• Clinical diagnosis of PsA meeting the CASPAR classification criteria;

• Low disease activity (4 < DAPSA ≤ 14) at the time of recruitment;

• Under stable pharmacological treatment with disease-modifying antirheumatic drugs (DMARDs) (conventional synthetic, targeted synthetic, or biological);

• Disease duration > 6 months;

• Absence of metabolic diseases.

Exclusion Criteria:

• BMI ≥ 27 kg/m²;

• Current or desired pregnancies (confirmed by pregnancy test);

• Disease activity in remission (DAPSA ≤ 4), moderate (14 < DAPSA ≤ 28), or high (DAPSA > 28) at the time of recruitment;

• Pediatric onset of the disease (< 16 years);

• Patients on a vegan, ketogenic, or MCT-rich diet (containing MCT in supplement formor high amounts of palm or coconut oil);

• Presence of ketoacidosis/metabolic acidosis, decompensated liver cirrhosis, ormedium-chain acyl-CoA dehydrogenase (MCAD) deficiency;

• Type 2 diabetes, cardiovascular diseases, hypertension, ischemic diseases, renalfailure, malignant tumors, respiratory diseases, dyslipidemia, fibromyalgia,metabolic syndrome;

• Major depression;

• Gastritis, esophagitis, reflux syndrome, chronic inflammatory bowel diseases (IBD);

• Lactose intolerance.