Deep Diaphragmatic Breathing: Neurobiological and Anti-inflammatory Effects

Life's dynamics in modern societies expose the individuals to high level of suffering and stress, which can affect both psychological and physiological well-being. Numerous scientific evidences showed the correlation between stress and immunity system dysregulation. The exposure to acute and\or chronic mental stress conditions can alter the physiological functions of the organism, through the activation of sympathetic nervous system (SNS) and the inhibition of the parasympathetic nervous system (PNS). The activation of peripheral and central immune-inflammatory pathways is indicated by increased levels of proinflammatory cytokines, such as Interleukin-1 β (IL-1β), Interleukin-6 (IL-6), and Tumor necrosis factor-α (TNFα). Furthermore, experiencing high stress levels may lead to a disruption of the Hypothalamic-Pituitary-Adrenal (HPA) axis, with consequent increasing of cortisol's level, low-grade systemic inflammation and oxidative stress. These results correlate with the develop and progression of a wide range of pathological conditions, such as cardiovascular disease, Type II diabetes, arthritis, osteoporosis, Alzheimer's disease, and depression. In addition, inflammation is now considered as a risk factor for most cancers' disease, promoting pathological mechanism such as proliferation, angiogenesis and metastases.

The last 20 years has seen an exponential growth of the mind-body techniques (MBT), an heterogeneous group of exercises and techniques focusing the life-styles, which has demonstrated validity in the reduction of psychological stress and inflammatory states. The techniques adopted by the clinical trials available include Yoga, Mindfulness, Tai Chi Chih, and Qigong; these protocols last usually from 4 to 12 weeks, and have been applied on clinical samples ranging on heterogeneous pathological conditions. However, the techniques used in the majority of these studies are derived from eastern meditative tradition and were not primarily developed to carrying out anti-inflammatory effects. Furthermore, the data concerning the effects of a single session of MBT under controlled experimental conditions are still lacking. In this regard, the Functional Therapy (FT) approach, an integrated body-mind therapy developed around the knowledges of psychoneuroimmunology (PNI), represents a potentially effective and specific methodology to counteract the physiological and psychological effects caused by prolonged exposure to stress conditions.

Given these premises, the aim of this clinical trial is to verify the efficacy of a single Functional Therapy (FT) session to relieve inflammations, decreasing cortisol levels and activating the parasympathetic nervous system in healthy subjects after the administration of an acute stress such as the Trier Social Stress Test (TSST).

Patients will be recruited starting in October 2019, via advertisement posted in university classrooms and premises. Researchers planned to recruit a sample of 40 participants. For the recruitment a structured telephone screening will help the researchers to investigate on some exclusion criteria. Then a consultation with a clinical psychologist and a psychiatrist will be programmed together with the administration of the psychological tests. Psychological assessment includes an ad-hoc sociodemographic questionnaire; a shortened version of Wechsler Adult Intelligence Scale - Revised (WAIS-R); Millon Clinical Multiaxial Inventory-III (MCMI-III); and Stress-related Vulnerability Scale (SVS). All these assessments will take place in the outpatient clinic of the policlinic "P. Giaccone", Palermo. After the assessment, eligible subjects will be randomized in the FT group or in the attention control group (AC), and will be assigned to the next therapist on a time capacity list.

All the sessions will be taking place in the Neo-Functional Psychotherapy Centre of Palermo. During the session, participants will be assessed for anthropometric, psychological, biofeedback and salivary parameters. Anthropometric parameters include height, weight, and BMI; Psychological assessment includes the State-Trait Anxiety Inventory, in both trait and state form; and Subjective Unit of Distress Scale. Biofeedback parameters include hearth rate, skin conductance, and electromyography. Salivary measurements include pro-inflammatory cytokines (IL-6, TNFα, IL1β), anti-inflammatory cytokine (IL-10), and cortisol.

Upon arrival, the anthropometric parameters will be assessed, thus biofeedback sensors will be connected to participants and it will record, for 5 minutes, the physiological parameters that will constitute the baseline; biofeedback sensors will remain online for the whole duration of the clinical trial. During this phase the STAI (trait and state) and SUDS questionnaires will be administered, and the first salivary samples will be taken for cortisol and cytokines.

Then, participants will be submitted to the TSST social stress, a protocol used by researchers to induce stress under controlled condition. TSST is divided in 5 minutes components and the whole procedure lasts approximately 15 minutes; at the end, the second psychological and salivary assessments will be carried out.

Participants will be randomized in FT group or AC group. Five different therapists with a 4-year postgraduate training on functional approach will apply the FT session. The treatment was specifically manualized to reducing stress condition and to relieve inflammatory states. Specifically, the treatment includes a variety of functional techniques such as diaphragmatic breathing, and thoracic and abdominal manipulation, designed to stimulate the neurofunctional interconnection between body, mind and immune system. The FT session will last 30 minutes. The participants assigned to the AC will listen an audiobook lasting for 30 minutes, which will be used as attention placebo control activity. At the end of the session, the third psychological and salivary assessments will be carried out.

Finally, all the participants will be undergoing to a follow-up phase, designed to assess the biofeedback and cytokines slow-responses to stress and relaxation procedures. Thus, subjects will be provided with an additionally 30 minutes session of audiobook listening, used as attention control placebo. At the end of the session, the fourth psychological and salivary assessments will be carried out.