Between Paws and Affections - Impact of Dog-Assisted Therapy in Fibromyalgia Patients

Between Paws and Affections: Impact of Dog Assisted Therapy on Pain, Emotional Symptoms, and Functioning in Fibromyalgia

The purpose of this study is to evaluate the effectiveness and medium-term maintenance of a structured dog-assisted therapy (DAT) protocol, "Entre Patas e Afetos" (Between Paws and Affections), in reducing pain, anxiety and depressive symptoms and in improving functional status and quality of life in Portuguese patients with fibromyalgia (FM) followed at ULS Alto Ave, with systematic outcome assessment in the immediate post intervention phase (T2), 6-month follow-up (T3) and 12-month follow-up (T4).

This is a prospective, non-randomized clinical trial with a control group, conducted at the Day Hospital of the Psychiatry and Mental Health Department of ULS Alto Ave, as an academic research project within a PhD in Medicine at the University of Minho.

The original pilot trial (Ref. 19/2024), including 34 women with FM, showed statistically significant improvements in maximum and average pain intensity, pain interference, total pain catastrophizing and its subscales (helplessness, magnification, rumination), anxiety (HADS) and functional impact (FIQ-P). However, depressive symptoms showed only a non-significant trend for improvement. Critically, analysis of 6-month follow-up data (T3) revealed partial erosion of the initial gains: pain intensity, pain interference, functional impact, and emotional symptoms showed variable maintenance patterns, with particular vulnerability to relapse in depressive symptoms, supporting the need for a prolonged intervention with maintenance sessions to consolidate gains and prevent deterioration over time.

The prolongation protocol comprises: (1) continuation of the initial control group with five monthly relaxation sessions; and (2) inclusion of a new intervention group receiving 10 DAT sessions (4 weekly structured dog-assisted therapy sessions plus 6 monthly guided-relaxation "booster" sessions with dogs) and a new active control group receiving an identical psychoeducational and relaxation program without dogs.

Sessions are group-based (up to 5 patients), last 60 minutes, and are delivered in a dedicated therapy room in the Psychiatry Day Hospital, by a multidisciplinary team (psychiatrist, psychologist, nurse, physiatrist) together with trained therapy dogs (Ari, Maica) and a professional dog handler, with appropriate veterinary follow-up and liability/health insurance.

Eligibility is assessed by a psychiatrist according to predefined inclusion and exclusion criteria; eligible patients provide written informed consent and complete baseline questionnaires (T1) up to four weeks before starting the intervention. Outcome assessments are performed immediately after session 4 (T2), at 6 months after session 4, and before session 10 (T3), and at 12 months after the end of the intervention (T4), in order to monitor the short-term response, the 6-month maintenance or progression of gains, and the 12-month trajectory associated with the monthly booster sessions. All procedures follow the previously approved protocol (Ref. 19/2024) and comply with the requirements of the institutional Ethics Committee and the Data Protection Officer, with no new data categories or processing purposes, and an addendum specifically for the extension of the study has been submitted and approved.

Inclusion Criteria:

• Age 18 years or older
• Confirmed diagnosis of fibromyalgia
• Being followed at ULS Alto Ave by the Multidisciplinary Pain Unit, Internal Medicine (Auto immune diseases), Physical and Rehabilitation Medicine or Neurology
• Ability to read and write Portuguese and to understand the study procedures
• Willingness and ability to participate voluntarily in the 10 session program and all scheduled assessments (T1-T4)
• Provision of written informed consent

Exclusion Criteria:

• Allergy to dogs or marked fear of dogs
• History of aggression towards animals
• History of oncological disease
• Concomitant systemic or rheumatologic disease that may confound pain and functional assessment
• Decompensated psychiatric disorder or severe cognitive impairment that may compromise comprehension of the protocol or adherence to the intervention
• Refusal to participate or withdrawal of consent at any point