ORIGINAL ARTICLE |
https://doi.org/10.5005/jp-journals-11010-1144 |
Prevalence of Dysfunctional Breathing in Subjects Undergoing Maintenance Dialysis: A Cross-sectional Study
1Department of Physiotherapy, MGM Institute of Physiotherapy, Chhatrapati Sambhaji Nagar, Maharashtra, India
2,4Department of Cardiovascular and Respiratory Physiotherapy, MGM Institute of Physiotherapy, Chhatrapati Sambhaji Nagar, Maharashtra, India
3Department of Neurophysiotherapy, MGM Institute of Physiotherapy, Chhatrapati Sambhaji Nagar, Maharashtra, India
Corresponding Author: Abhishek S Mishra, Department of Cardiovascular and Respiratory Physiotherapy, MGM Institute of Physiotherapy, Chhatrapati Sambhaji Nagar, Maharashtra, India, Phone: +91 8296367355, e-mail: abhishekmishra@mgmiop.edu.in
Received: 03 June 2024; Accepted: 27 December 2024; Published on: 17 February 2025
ABSTRACT
Aim: To determine the prevalence of dysfunctional breathing (DB) in subjects undergoing maintenance dialysis.
Background: DB involves abnormal breathing patterns either without organic disease or secondary to cardiopulmonary/neurological conditions like asthma or heart failure. Indicators include asynchronous thoracic and abdominal movements, upper thoracic breathing, frequent sighs, mouth breathing, and excessive use of accessory respiratory muscles. DB can be assessed using the Nijmegen Questionnaire (NQ) and the Self-evaluation of Breathing Questionnaire (SEBQ). The NQ, with a sensitivity of 91% and specificity of 95%, considers a score above 23 indicative of DB. The SEBQ, with an intraclass correlation coefficient of 0.89, uses a cutoff score of 11 for DB. Additionally, the Manual Assessment of Respiratory Motion (MARM) helps assess DB through physical examination.
Materials and methods: The study enrolled 69 participants aged 18–60 who had undergone more than three dialysis cycles. Exclusions included chronic respiratory disease, recent abdominal surgeries, and smoking. Participants completed the NQ and SEBQ, followed by an MARM physical assessment.
Results: The average age of participants was 41.8 ± 10.9 years. Of the 69 subjects, 21 scored above 23 on the NQ, indicating DB in 30.43% of the sample. On the SEBQ, 66 subjects scored above 11, indicating DB in 95.65%. MARM helped identify abnormal breathing patterns and asymmetry.
Conclusion: Using the NQ and SEBQ, the prevalence of DB in subjects undergoing dialysis was found to be 30.43 and 95.65%, respectively.
Keywords: Dialysis, Dysfunctional breathing, Manual assessment of respiratory motion, Nijmegen Questionnaire, Self-evaluation of breathing questionnaire
How to cite this article: Bora ND, Mishra AS, Ganachari PS, et al. Prevalence of Dysfunctional Breathing in Subjects Undergoing Maintenance Dialysis: A Cross-sectional Study. Indian J Respir Care 2024;13(4):238–242.
Source of support: Nil
Conflict of interest: None
HIGHLIGHT
This study found that dysfunctional breathing (DB) is highly prevalent among dialysis patients, with 30.43 and 95.65% showing DB based on the Nijmegen Questionnaire and Self-evaluation of Breathing Questionnaire, respectively. These findings highlight the need for regular DB assessments in this population.
INTRODUCTION
Chronic kidney disease (CKD) stands as one of the most pervasive health challenges globally, presenting a significant burden on healthcare systems and affecting millions worldwide.1 Characterized by renal injury or diminished kidney function persisting for 3 months or longer, CKD progresses gradually, leading to irreversible loss of kidney function, ultimately culminating in end-stage renal disease.2 Data from the Screening and Early Evaluation of Kidney Disease (SEEK) initiative reveals a concerning prevalence, with 17.2% of cases identified, with 6% classified as stage 3 CKD.3 Notably, patients admitted to intensive care units often face the compounding challenge of multiple organ failure, necessitating interventions such as dialysis and ventilator support.4 In regions like India, where healthcare infrastructure faces escalating demands, the prevalence of CKD is starkly evident, with over 55,000 individuals estimated to require dialysis, a number that continues to rise annually by 10–20%.5
The intricate interplay between CKD, dialysis treatment, and individual predispositions, particularly in the context of preexisting lung conditions, underscores the potential compromise of respiratory function in renal failure.6,7 Among hemodialysis patients, connection to the dialysis pump frequently leads to the development of hypoxemia. Studies have demonstrated a rapid decline in PaO2 levels shortly after the initiation of hemodialysis, often by 10–15 mm Hg or more within 30–60 minutes, followed by a subsequent return to predialysis levels upon completion of the procedure.8 However, routine dialysis therapy may also introduce various thoracic complications due to factors such as inadequate fluid management, suboptimal catheter placement, malfunctioning vascular catheters, and complications arising from central venous catheterization.9
Collectively, these respiratory variables can significantly impact an individual’s breathing patterns, manifesting in symptoms such as dyspnea, mouth breathing, and increased utilization of accessory muscles for respiration. At times, these symptoms may signal an underlying respiratory ailment. DB represents one among several respiratory conditions that are often either undiagnosed or misdiagnosed. Typically characterized by aberrant breathing patterns,10,11 DB can be categorized as primary, occurring in the absence of organic diseases and attributed to psychogenic factors like anxiety,12,13 secondary, arising due to organic or physiological causes such as asthma or heart failure, or a combination of both.14,15
Given the intricate and multifaceted nature of DB, a comprehensive multidimensional assessment is imperative for accurately diagnosing this respiratory ailment. Three pivotal domains—biochemical factors, biomechanical aspects, and respiratory symptoms16—require thorough investigation to enhance our understanding of DB. Current research suggests that techniques such as Manual Assessment of Respiratory Motion (MARM) have predominantly been utilized to evaluate respiratory muscle activity, particularly in individuals with conditions like Down syndrome, to detect thoracic or paradoxical breathing patterns.17,18 MARM aims to delineate breathing patterns and assess the distribution of breathing motion across the upper and lower rib cages and the abdomen. Given DB’s multifaceted nature, employing a combination of subjective and objective parameters is preferable during assessment. The Nijmegen Questionnaire (NQ), for instance, employs a 5-point scale to evaluate 16 signs and symptoms of irregular breathing, with a total symptom score exceeding 23 demonstrating high sensitivity (91%) and specificity (95%) in screening for hyperventilation syndrome.19 Similarly, the Self-Evaluation of Breathing Questionnaire (SEBQ), comprising 25 items, exhibits strong reliability (intraclass correlation coefficient of 0.89) and can be utilized to gauge the severity of breathing-related complaints,16 with a score exceeding 11 indicating potential breathing difficulties associated with DB. Our objective is to ascertain the prevalence of DB and enhance healthcare practitioners’ understanding of this condition in patients undergoing dialysis, utilizing the aforementioned tools. A comprehensive comprehension of DB complexities can facilitate the development of tailored medical interventions to address the needs of dialysis patients and mitigate associated consequences effectively.
MATERIALS AND METHODS
Study Design
A cross-sectional study was conducted to evaluate the prevalence of DB in subjects undergoing maintenance dialysis.
Setting and Participant Recruitment
The study took place at a tertiary care hospital in Aurangabad, Maharashtra, India, spanning the recruitment period from December 2021 to May 2022. Inclusion criteria involved subjects aged 18–60 years, regardless of gender, diagnosed with CKD and having undergone at least 3 cycles of maintenance dialysis. Exclusion criteria comprised individuals with (1) chronic respiratory diseases, (2) recent thoracic or abdominal surgery, (3) a history of neurological or psychiatric disorders, (4) chronic smokers, and (5) acute systemic illness.
Ethical Consideration
The study received approval from the Institutional Ethics Committee (MGM/IOP/IEC/UG/2021/04).
Outcome Measures
The Nijmegen Questionnaire (NQ) and Self-Evaluation of Breathing Questionnaire (SEBQ) are two tools used to assess DB. The NQ, with a sensitivity of 91% and a specificity of 95%, consists of 16 complaints, with a cutoff value of >23 indicating the presence of DB. The SEBQ has an intraclass correlation coefficient of 0.89, with a cutoff of >11, which suggests DB. Along with the NQ and SEBQ, a physical assessment method called MARM was also used to assess DB.16,19
RESULTS
A total of 118 participants underwent screening for inclusion in the study. Among them, 69 participants (52 men and 17 women) were enrolled. The remaining 49 individuals were excluded for various reasons: 22 did not provide consent, 8 were smokers, 3 had recent abdominal surgery, 8 had acute systemic illness, and 8 had previously diagnosed chronic respiratory diseases. Demographic data, encompassing age, sex, medical history, and current disease status, were collected from all participants. Those meeting the inclusion criteria and consenting to participate completed a consent form. Subsequently, participants filled out the Nijmegen Questionnaire and Self-Evaluation of Breathing Questionnaire prior to their dialysis cycle. Following questionnaire completion, participants underwent assessment using the MARM procedure, a palpation-based technique where the examiner interprets and estimates motion perceived at the posterior and lateral lower rib cage. The MARM procedure involves evaluation in eight different positions, focusing on four aspects: area, average, balance, and percentage of rib cage movement.20
Table 1 provides a comprehensive summary of demographic and clinical characteristics of the 69 participants enrolled in the study. The mean age of participants was 41.8 years (SD = 10.9), indicating a diverse age distribution ranging from 21 to 65 years. Participants had an average height of 5.41 feet (SD = 0.38) and weight of 53.7 kg (SD = 11.4), resulting in a mean body mass index (BMI) of 19.9 kg/m2 (SD = 4.9). Notably, the duration of dialysis treatment varied widely among participants, with a median duration of 9 months [interquartile range (IQR) = 5–24 months], highlighting considerable heterogeneity in the duration of dialysis therapy among individuals.
| Characteristics | Mean ± SD/median (IQR) |
|---|---|
| Age | 41.8 ± 10.9 |
| Height | 5.41 ± 0.38 |
| Weight | 53.7 ± 11.4 |
| BMI | 19.9 ± 4.9 |
| Dialysis duration | 9 (5 – 24) |
IQR, interquartile range; SD, standard deviation; age, years; height, feet; weight, kg; BMI, kg/m2; dialysis duration in months
Table 2 shows the distribution of participants exhibiting DB, identified by Nijmegen Questionnaire (NQ) scores exceeding 23 and Self-Evaluation of Breathing Questionnaire (SEBQ) scores surpassing 11. These threshold scores indicate the presence of DB symptoms. The analysis reveals that 30.43% of participants met the criteria for DB based on NQ scores, while a notably higher prevalence of 95.65% was observed using SEBQ criteria. Additionally, the table presents the mean NQ score of 20.71 with a standard deviation of 4.60, and the mean SEBQ score of 19.71 with a standard deviation of 6.06, indicating the average severity of DB symptoms among participants. Confidence intervals (CI) for NQ and SEBQ scores are also provided, with the CI for NQ scores ranging from 19.62 to 21.78, and the CI for SEBQ scores ranging from 18.28 to 21.14. These confidence intervals offer insights into the precision and reliability of the mean scores, further elucidating the distribution and severity of DB within the study population.
| Results | No. of patients | Mean scores ± SD (95% CI) | Percentage |
|---|---|---|---|
| NQ score >23 | 21 | 20.71 ± 4.60 (19.62, 21.78) | 30.43% |
| SEBQ score >11 | 66 | 19.71 ± 6.06 (18.28, 21.14) | 95.65% |
NQ cutoff >23; NQ, Nijmegen Questionnaire; SEBQ cutoff >11; SEBQ, Self-Evaluation of Breathing Questionnaire
Figure 1 illustrates the distribution of participants based on Nijmegen Questionnaire (NQ) scores and Self-Evaluation of Breathing Questionnaire (SEBQ) scores, categorized into score ranges. The blue bars represent the percentage of participants corresponding to NQ scores, while the red bars represent SEBQ scores. For NQ scores, the majority of participants (59.4%) fell within the score range of 20–30, followed by 36.2% in the range of 10–20. A smaller percentage of participants were distributed across other score ranges, with 4.3% in the 30–40 range and no participants in the 0–10 and 40–50 ranges. In contrast, for SEBQ scores, the highest percentage of participants (52.1%) were observed in the 20–30 score range, followed by 40.5% in the 10–20 score range. Notably, 4.3% of the participants were in the 0–10 range for SEBQ scores, and only a minimal percentage were in the 30–40 and 40–50 score ranges (1.44%).
Fig. 1: Percentage distribution
Table 3 displays the mean and standard deviation (SD) of Motion Amplitude Respiratory Motion (MARM) at eight different steps, analyzed across four dimensions: area, average, balance, and percentage of ribcage movement. These dimensions were assessed bilaterally, indicating measurements for both the right and left sides of ribcage movement. Under the “Area” dimension, the mean and SD values for the right side are reported as follows: normal (101.7 ± 5.88), slumped (102.9 ± 6.83), upright (107.9 ± 8.26), abdominal (91.3 ± 10.62), thoracic (111.1 ± 6.92), large volume (112.9 ± 6.39), small volume (97.31 ± 4.38), and normal (100.8 ± 5.31). Similarly, values for the left side are given for each step. For the “Average” dimension, mean and SD values for the right and left sides are presented similarly for each step. Under “Balance,” the mean and SD values for both sides are shown for each step, while under “% Ribcage Movement,” values for both sides are also provided for each step.
| Aspect | Step | Right side (mean ± SD) | Left side (mean ± SD) |
|---|---|---|---|
| Area | Normal | 101.7 ± 5.88 | 101.1 ± 6.26 |
| Slumped | 102.9 ± 6.83 | 102.0 ± 6.93 | |
| Upright | 107.9 ± 8.26 | 106.6 ± 8.10 | |
| Abdominal | 91.3 ± 10.62 | 91.1 ± 9.50 | |
| Thoracic | 111.1 ± 6.92 | 110.0 ± 8.07 | |
| Large volume | 112.9 ± 6.39 | 112.3 ± 6.62 | |
| Small volume | 97.31 ± 4.38 | 96.3 ± 4.78 | |
| Normal | 100.8 ± 5.31 | 99.7 ± 6.13 | |
| Average | Normal | 67.46 ± 5.55 | 66.88 ± 5.96 |
| Slumped | 65.5 ± 6.08 | 64.63 ± 6.27 | |
| Upright | 70.28 ± 7.93 | 70.29 ± 7.60 | |
| Abdominal | 73.4 ± 8.94 | 72.46 ± 9.38 | |
| Thoracic | 76.81 ± 9.72 | 75.65 ± 10.5 | |
| Large volume | 81.66 ± 10.3 | 80.94 ± 10.87 | |
| Small volume | 59.89 ± 4.0 | 59.23 ± 4.06 | |
| Normal | 65.65 ± 5.24 | 65.07 ± 5.86 | |
| Balance | Normal | 73.47 ± 5.05 | 73.76 ± 5.41 |
| Slumped | 75.94 ± 4.91 | 76.37 ± 5.09 | |
| Upright | 73.04 ± 6.21 | 73.04 ± 6.43 | |
| Abdominal | 61.59 ± 9.2 | 62.46 ± 9.23 | |
| Thoracic | 68.11 ± 6.86 | 68.84 ± 7.52 | |
| Large volume | 63.47 ± 8.65 | 63.91 ± 9.04 | |
| Small volume | 78.76 ± 3.44 | 78.91 ± 3.28 | |
| Normal | 74.78 ± 5.27 | 74.78 ± 5.27 | |
| % ribcage movement | Normal | 29.72 ± 5.78 | 28.69 ± 6.87 |
| Slumped | 28.21 ± 6.69 | 26.62 ± 7.26 | |
| Upright | 33.76 ± 7.54 | 33.02 ± 7.99 | |
| Abdominal | 33.01 ± 9.16 | 31.73 ± 9.67 | |
| Thoracic | 40.02 ± 6.81 | 38.06 ± 8.91 | |
| Large volume | 44.33 ± 7.77 | 43.88 ± 8.21 | |
| Small volume | 22.04 ± 6.3 | 20.34 ± 7.01 | |
| Normal | 28.1 ± 4.38 | 26.58 ± 6.76 |
%, percentage
DISCUSSION
The purpose of the study was to estimate the prevalence of DB in maintenance dialysis patients, as these patients may exhibit breathing problems due to changes in their respiratory biomechanics. Patients on maintenance dialysis for CKD were evaluated for disordered breathing using the Nijmegen Questionnaire, the Self-Evaluation of Breathing Questionnaire, and the MARM. The mean and SD of the utility ratings for disordered breathing in patients receiving continuing dialysis therapy were reported to be 20.71 ± 4.60. According to the SEBQ, the utility scores had a mean and SD of 19.71 ± 6.06 each. For individuals who may not consistently exhibit breathing dysfunction in the biomechanical or biochemical dimensions, the SEBQ assesses respiratory symptoms and breathing behaviors that have been documented to be linked with DB.16
Patients with asthma receiving care at the PHC at the University of Leicester reported a prevalence of DB of 29%.21 Using the NQ, studies on asthma patients in Spain found a prevalence of 36% overall, with 47% of females and 19.6% of men.22 In Scotland, a high frequency of 64% was found.23 These studies largely concentrated on asthmatics, but when considering the variables that affect dialysis patients and the paucity of literature on DB in these individuals, it became crucial to determine the prevalence rate in them. When employing the SEBQ instead of the NQ, the prevalence of DB in persons receiving maintenance dialysis was reported to be 95.65%, as opposed to 30.43% when using the NQ. The majority of participants, it is estimated, have breathing problems, which occasionally go undiagnosed or underdiagnosed. Many individuals had scores that were near to the cutoff, meaning that if adequate action is not taken at this time, they are more likely to acquire DB. Women were also more likely than men to develop DB. All of these estimates can assist us in creating a fresh strategy for treating DB patients with specific maneuvers.
This study also revealed that there is greater asymmetry in the motions at the upper ribcage, as people were found to breathe more thoracic-style. Few individuals were able to commence abdominal breathing, making it difficult to practice. In contrast to the predominantly thoracic breathing pattern in an upright position, the breathing pattern while slouched was significantly decreased. The participants noted that when the cycle duration was extended by more than one day, they experienced more difficulty. We also discovered that the participants had become accustomed to their respiratory issues. They began to think of those issues as being related to their renal condition, and as a result, they appeared to be ignoring them. DB is greatly influenced by the illness itself, ongoing dialysis cycles, and medications.8 Hence, the respiratory condition was adversely affected.
The patients in this research were also shown to be less conscious of their respiratory problems. The questionnaires were a bit challenging to fill out since the individuals weren’t as aware of the associated symptoms. They showed little concern for their symptoms and did not engage in any exercises or activities that would have helped them deal with their breathing problems. This study improved knowledge of DB in those on maintenance dialysis and managing CKD. Participants were encouraged to examine their own breathing issues carefully, pay close attention to their symptoms, and seek appropriate treatment.
The strength of the study was the use of both subjective and objective tools to assess DB. The study fostered a sense of awareness among the individuals toward the breathing abnormalities. It focused on bringing DB, the underdiagnosed and misdiagnosed topic, into consideration. Not only were the breathing symptoms assessed, but also the symmetry of ribcage and abdominal movements.
CONCLUSION
Our study reveals a notable prevalence of DB among CKD patients undergoing maintenance dialysis. These findings emphasize the critical need for thorough respiratory assessments in this patient population, which can guide the development of personalized interventions to address DB and improve overall patient care.
Limitations
One limitation of the study is its small sample size, which may affect the generalizability of the findings to a broader population of CKD patients undergoing maintenance dialysis. Furthermore, the notable difference in prevalence rates of DB as measured by the Self-Evaluated Breathing Questionnaire (SEBQ) and the Nijmegen Questionnaire presents another limitation to consider.
ORCID
Neha D Bora https://orcid.org/0009-0007-4348-1798
Abhishek S Mishra https://orcid.org/0000-0002-4097-5342
Preeti S Ganachari https://orcid.org/0000-0002-7323-0216
Santosh P Dobhal https://orcid.org/0000-0003-4895-9141
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