Overview
Interoception refers to the process of perceiving and interpreting internal physiological signals and plays a central role in symptom perception. In conditions with a high symptom burden such as chronic obstructive pulmonary disease (COPD), clinical features including dyspnea perception, depression, and sleep quality may be influenced not only by disease severity but also by the interpretation of internal bodily signals.
Recent evidence suggests that respiratory-related internal signals are transmitted to the central nervous system through multiple afferent pathways and integrated within cortical and subcortical networks, contributing to subjective experiences such as dyspnea. In this context, dyspnea perception may arise from the interaction between disease severity and interoceptive processes.
Depressive symptoms and impaired sleep quality are also closely associated with interoceptive processes and may contribute to the perception of respiratory symptoms. However, studies simultaneously examining interoception, disease severity, dyspnea perception, depression, and sleep quality in hospitalized patients with acute COPD exacerbation are limited.
This prospective, observational, cross-sectional study will include 50 individuals aged 40 years and older who are hospitalized with acute COPD exacerbation in a Chest Diseases clinic. Data will be collected at a single time point when patients are clinically stable, without interfering with routine clinical care. Participants will be recruited using a consecutive sampling method.
Sociodemographic and clinical data will be obtained from patient records and a structured data collection form. Disease severity will be assessed using oxygen requirement, respiratory rate, oxygen saturation, and arterial blood gas values when available. Interoception will be evaluated using the Multidimensional Assessment of Interoceptive Awareness (MAIA-2). Symptom burden will be assessed with the COPD Assessment Test (CAT), dyspnea with the Modified Medical Research Council (mMRC) scale, sleep quality with the Richards-Campbell Sleep Questionnaire (RCSQ), and depressive symptoms with the Hospital Anxiety and Depression Scale - Depression subscale (HADS-D).
Statistical analyses will be performed using IBM SPSS Statistics software. Relationships between variables will be analyzed using Pearson or Spearman correlation depending on data distribution, with a significance level of p\<0.05.
Description
Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) represent critical events characterized by a sudden worsening of respiratory symptoms, including dyspnea, cough, and sputum production, often leading to increased healthcare utilization, hospitalization, and mortality. Despite advances in pharmacological and supportive management, considerable heterogeneity exists in how patients perceive and report symptoms during exacerbations. This variability cannot be fully explained by physiological impairment alone and suggests an important role for altered interoceptive processing.
Interoception refers to the sensing, interpretation, and integration of internal bodily signals, including respiratory sensations such as dyspnea, air hunger, and breathing effort. In COPD, especially during acute exacerbations, structural and functional changes in the respiratory system (e.g., airflow limitation, dynamic hyperinflation, and gas exchange abnormalities) interact with central perceptual and cognitive-emotional processes. Consequently, symptom perception is not solely determined by objective physiological parameters but is shaped by interoceptive accuracy, interoceptive sensibility, and interoceptive awareness.
Emerging evidence suggests that patients with COPD may exhibit altered interoceptive processing, leading to either heightened sensitivity (over-perception) or blunted awareness (under-perception) of respiratory symptoms. Under-perception may delay care-seeking behavior and increase the risk of severe exacerbations and adverse outcomes, whereas over-perception may contribute to anxiety, increased symptom burden, and unnecessary healthcare use. However, the mechanisms underlying these differences remain insufficiently understood, particularly in the acute exacerbation setting.
This study aims to investigate the relationship between interoception and symptom perception in patients experiencing AECOPD. Specifically, the study will evaluate how different dimensions of interoception-such as interoceptive accuracy (objective performance in detecting internal signals), interoceptive sensibility (self-reported perception), and metacognitive awareness-are associated with the intensity and variability of respiratory symptoms during exacerbation.
Participants diagnosed with AECOPD will be recruited in a hospital setting. Following eligibility screening and informed consent, participants will undergo a comprehensive assessment protocol. Demographic and clinical data, including age, sex, smoking history, disease severity, comorbidities, and prior exacerbation frequency, will be collected. Clinical status during exacerbation will be documented using standard measures such as symptom scores, vital signs, and, where available, pulmonary function parameters.
Interoceptive processing will be assessed using a multimodal approach. Behavioral tasks designed to quantify interoceptive accuracy (e.g., respiratory-related perception tasks or adapted detection paradigms) will be administered. In parallel, validated self-report instruments will be used to evaluate interoceptive sensibility and awareness, including multidimensional questionnaires capturing attention to bodily sensations, emotional appraisal, and regulatory aspects of interoception. Symptom perception will be quantified using standardized dyspnea scales and patient-reported outcome measures specific to COPD.
The study will also explore the influence of psychological factors, such as severity of symptoms, sleep, anxiety and depression, on the relationship between interoception and symptom perception.
Eligibility
Inclusion Criteria:
- Physician-confirmed diagnosis of acute exacerbation of COPD with hospitalization
- Age 40 years or older
- Conscious and able to communicate
- Willing to participate and provide written informed consent
Exclusion Criteria:
- Presence of delirium or severe cognitive impairment
- Requirement for invasive mechanical ventilation
- Clinical instability preventing safe administration of assessment tools
- History of severe neurological or psychiatric disorders
- Any history of malignancy
- Presence of pneumonia
- History of stroke
