European Journal of Cardiovascular Medicine

Dyspnoea, coughing, and increased production and purulence of sputum are symptoms of chronic obstructive pulmonary disease (COPD), which can sometimes deteriorate rapidly. Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) describes this extreme worsening of symptoms all at once. Chronic obstructive pulmonary disease (COPD) exacerbations are common and can have serious consequences for people's health and well-being. They can lead to a decline in quality of life, impaired lung function and exercise capacity, hospitalisation, and even death.[1-2] Prospective studies have shown that patients who have already had an exacerbation are far more likely to have another one in the future.[3] An increased likelihood of exacerbations is associated with a history of chronic bronchitis, more severe symptoms, radiographic evidence of emphysema, and inadequate baseline lung function.[4]

Clinicians and researchers in the last 20 years have started to recognize the significance of maintenance treatment for stable chronic obstructive pulmonary disease (COPD) in preventing or reducing the occurrence of exacerbations, expanding the therapeutic aims for COPD beyond just restoring lung function and symptoms. The effectiveness ofxchronic obstructive pulmonary disease (COPD) treatments is now being evaluated in a large number of randomized clinical trials by looking at AECOPD incident rates.[7,6] Exacerbations of chronic obstructive pulmonary disease (COPD) must be precisely characterized and easily quantified in clinical practice and research investigations due to the growing clinical, economic, and scientific significance of AECOPD.

Essential for regular breathing, electrolytes in the blood include Sodium, potassium, calcium, and chloride. Patients with AECOPD may find their conditions worsened when disturbances in these electrolytes cause serious clinical effects such arrhythmias, respiratory failure, and weak muscles. Hyponatremia, hypokalemia, and hypocalcemia have been identified as prevalent electrolyte imbalances in chronic obstructive pulmonary disease (COPD) patients during exacerbations, according to some previous research.

Acute respiratory acidosis or worsening of pre-existing chronic respiratory acidosis is caused by the abrupt decrease in breathing that happens during COPD exacerbations, which is also known as hypercapnia. In critically sick and elderly patients, in particular, combined acid-base and hydro-electrolyte disorders are on the rise due to the high prevalence of comorbidities[7] and the related multi-drug treatments.[8]

Limited healthcare resources, poor access to specialized care, and environmental exposures that may worsen the condition are some of the particular obstacles in managing chronic obstructive pulmonary disease (COPD) in the Koshi region, a mostly rural area. Improving the care and outcomes of AECOPD patients requires understanding the pattern of serum electrolyte abnormalities in this specific geographic environment.

Patients in the Koshi area who arrive with AECOPD will have their serum electrolyte levels checked. Reducing the severity of exacerbations and improving patient outcomes can be achieved by identifying frequent electrolyte abnormalities in this population and then tailoring therapy techniques to address these issues.

Study Setting and Design: This prospective hospital-based study was conducted at Katihar Medical College and Hospital in Bihar, India, from July 2022 to December 2023, spanning 18 months. The primary aim was to assess the clinical and biochemical profiles of COPD patients experiencing acute exacerbations.

Source of Study: Primary data was collected from COPD patients admitted with acute exacerbations in the medical ward of Katihar Medical College and Hospital.

Period of study: July 2022 to December 2023, spanning 18 months

Inclusion Criteria –

• COPD patients presenting to the outpatient emergency department with acute exacerbations.

Exclusion Criteria –

• COPD patients admitted for reasons other than exacerbations.
• Patients with pre-existing renal, hepatic, endocrinal, or cardiac illnesses.
• Pregnant women.

Methodology

Data were collected prospectively from patients diagnosed with COPD admitted for acute exacerbations at Katihar Medical College and Hospital. Each patient underwent a series of standardized evaluations at admission and discharge to track the progression and response to treatment. Clinical history, mMRC dyspnea scale scores, and routine physical examinations were recorded. Diagnostic imaging and pulmonary function tests were performed to confirm the severity of COPD and the nature of the exacerbation.

Statistical Analysis

Data were analyzed using SPSS software (version 26.0). Descriptive statistics such as means, standard deviations, and percentages were used to summarize the demographic and clinical characteristics of the study population. Inferential statistics, including chi-square tests for categorical variables and t-tests for continuous variables, were employed to explore the relationships between COPD severity, treatment outcomes, and serum electrolyte levels. A p-value of less than 0.05 was considered statistically significant, indicating a meaningful difference or relationship.

Table: Distribution of Symptoms among study Population

Table: SPo2 Level among study Population

Table: Dyspnea Severity Based on mMRC Scale in AE COPD Participants

Table: Serum Sodium Levels in AE COPD Participants

Table: Serum Potassium Levels in AE COPD Participants

Table: Association between COPD GOLD Staging with Serum Sodium and Serum Potassium Levels

In our study, 63 (63%) patients had Fever, 100 (100%) patients had Cough, 73 (73%) patients had Crepitations and 90 (90%) patients had Wheeze. In our study, 77 (77 %) patients had 94-85 SPO2 Level, 22 (22 %) patients had 84-75 SPO2 Level, 1 (1 %) patient had <75 SPO2 Level. In our study, 25 (25 %) patients had 1 mMRC Scale, 35 (35 %) patients had 2 mMRC Scale, 25 (25 %) patients had 3 mMRC Scale and 15 (15 %) patients had 4 mMRC Scale. In our study, 44 (44%) patients had <135 (Hyponatremia) and 56 (56%) patients had 135-145 (Normal). In our study, 49 (49.0%) patients had <3.5 (Hypokalemia) and 51 (51.0%) patients had 3.5-5.0 (Normal).

In Sodium <135 mEq/L (n=43), 5 patients had Stage 1 COPD GOLD Staging, 15 patients had Stage 2 COPD GOLD Staging,14 patients had Stage 3 COPD GOLD Staging,10 patients had Stage 4 COPD GOLD Staging. In Sodium 135-145 mEq/L (n=57), 15 patients had Stage 1 COPD GOLD Staging, 25 patients had Stage 2 COPD GOLD Staging, 16 patients had Stage 3 COPD GOLD Staging. Association of COPD GOLD Staging with Serum Sodium Levels was statistically significant (p=0.0009). In Potassium <3.5 mEq/L (n=49), 6 patients had Stage 1 COPD GOLD Staging, 17 patients had Stage 2 COPD GOLD Staging, 18 patients had Stage 3 COPD GOLD Staging and 8 patients had Stage 4 COPD GOLD Staging. In Potassium 3.5-5.0 mEq/L (n=51), 14 patients had Stage 1 COPD GOLD Staging, 23 patients had Stage 2 COPD GOLD Staging, 12 patients had Stage 3 COPD GOLD Staging and 2 patients had Stage 4 COPD GOLD Staging. Association of COPD GOLD Staging with Serum Potassium Levels was statistically significant (p=0.031).

Our data on acute exacerbation of chronic obstructive pulmonary disease (COPD) shows that the majority of patients are middle-aged or older, with 56% falling into the 51-70 age bracket. The bulk of chronic obstructive pulmonary disease (COPD) exacerbations were observed in the 50-70 year age range, which aligns with the results reported in a study by Singh et al. (2019) [9]. Our study's 74% male and 26% female participant sex mix is consistent with the historical trend of COPD being more common in men. Possible explanations for the increased occurrence in men include more occupational exposures and higher rates of smoking. Findings from the TORCH trial (Calverley et al., 2007)[10] indicating severe exacerbations were most common in patients with a considerable smoking history and older age are similar with our findings that AE COPD is prevalent among older persons, mainly males. There needs to be targeted intervention in these high-risk populations because the frequency and severity of exacerbations increase with age and smoking history.

The fact that 66% of the people in our study were smokers shows that smoking is still a major contributor to chronic obstructive pulmonary disease (COPD) and its worsening. By Lopez-Campos JL et al. (2016)[11] proven that smoking increases the risk of chronic obstructive pulmonary disease (COPD) exacerbations by inflaming the airways and lung tissue. Whereas environmental contaminants and genetic predispositions can greatly contribute to the development of disease, 34% of the participants in our study did not smoke. Results from studies conducted by Eisner, Anthonisen, Coultas, et al. (2010) corroborate this particular element.[12].

We found that 37% of the people who took part in the study were exposed to biomass, which is another major environmental hazard. In underdeveloped nations where biomass is the main energy source for households, using it for cooking and heating is known to increase the risk of respiratory ailments (Ramírez-Venegas A et al., 2006).[13].

One of the most prevalent symptoms experienced by all individuals in our study was coughing. Research by Smith MC et al. (2014)[14] indicates that persistent airway inflammation and mucus hypersecretion contribute significantly to the development of cough as a symptom. In 90% of instances, wheezing was noted as an indication of airway blockage. The airway narrowing caused by inflammation, mucosal oedema, and bronchoconstriction is consistent with the high incidence of wheezing in individuals with chronic obstructive pulmonary disease (COPD) (Jones PW et al 2009).[15].

Acute exacerbations of chronic obstructive pulmonary disease (COPD) are sometimes complicated by co-occurring diseases, such as pneumonia; 73% of patients reported crepitations and 63% reported fever. These symptoms should be carefully considered since they can help doctors decide whether to provide antibiotics or order additional tests to diagnose infections (Uzun S et al., 2014).[16].

The bulk of the subjects (77%) kept their SpO2 levels between 94 and 85%, 22% kept them between 84% and 75%, and a mere 1% kept them below 75%. The severity of the disease may explain the observed fluctuation in SpO2 levels, with lower values indicating more severe disease. Consistent with previous research, this trend holds (Khor YH, et al., 2024)[17].

A chronic course with likely recurring exacerbations was indicated by the majority of patients (59%), who had a COPD diagnosis for more than 10 years. This time frame is frequently linked to more advanced COPD stages and lends credence to the literature that shows a correlation between longer illness duration and more frequent exacerbations and morbidity (Zatloukal J, et al 2020).[18] These results highlight the importance of a variable oxygen saturation level during exacerbations and the need for a personalised strategy for chronic obstructive pulmonary disease (COPD) management.

A quarter of the patients in the group experience severe dyspnoea, which indicates that they require active management measures to enhance their functional status and quality of life.

In addition, 35% of the participants experience moderate symptoms (level 2 on the mMRC scale), making them the largest portion of the sample. Although dyspnoea hinders these patients' ability to go about their everyday lives, the symptoms may be controllable with the right kind of treatment and therapies, according to the prevalence. It is worth noting that 15% of individuals fall into the most severe category (mMRC scale level 4), suggesting that their symptoms are so severe that they probably struggle to carry out even the most basic of tasks. This population is at a heightened risk for healthcare utilisation and hospitalisations.

The results show that hyponatraemia, defined as serum sodium levels lower than 135 mEq/L, affects 44% of the subjects. Hypoxic respiratory failure is one of the causes of hyponatraemia in chronic obstructive pulmonary disease (COPD) patients. This is because hypoxia can stimulate the release of antidiuretic hormone (ADH), which in turn causes water retention and a decrease in serum sodium levels. An important clinical finding in chronic obstructive pulmonary disease (COPD) patients is hyponatraemia, which has been associated with an increased risk of hospitalisation, a lengthier hospital stay, and even greater fatality rates (Funk GC, et al., 2010).[19].

Hypokalaemia, defined as a potassium level below the normal range, affects nearly half of the individuals (49%) according to the serum potassium analysis. Hypokalaemia can be caused by the commonly used beta-agonists, steroids, and diuretics for the treatment of AE COPD. Monitoring and maintaining potassium levels during exacerbations is crucial, as the effects of hypokalaemia go beyond muscle weakness and include cardiovascular dangers such arrhythmias.[20]

The study cohort had an average Forced Expiratory Volume in one second (FEV1) of 54.50 ±17.93. While this shows that there is a lot of variation across the subjects, on average there is a moderate amount of airflow restriction. The forced expiratory volume in one second (FEV1) is an important metric for the diagnosis and evaluation of chronic obstructive pulmonary disease (COPD). This finding is in line with worldwide statistics showing that FEV1 levels are frequently used to categorise the severity of (COPD) and to forecast the likelihood of future exacerbations and deaths.[21]

There was a standard deviation of 10.68 and a mean Forced Vital Capacity (FEV1/FVC) ratio of 56.87. When this ratio is below 70%, it usually means that there is a lot of airflow restriction, which is indicative of (COPD). Important chronic obstructive pulmonary disease (COPD) pathology was confirmed by the mean ratio of our investigation, which indicates moderate to severe obstruction. These findings are fundamental for the diagnosis and treatment of chronic obstructive pulmonary disease (COPD) since they prove that the participants' lung illness is obstructive. Celli BR et al. (2004) found that this ratio is useful for categorising the severity of COPD and directing treatment decisions since it highlights the progressive and persistent airflow restriction that is characteristic of the condition.[22]

Patients experiencing an Acute Exacerbation (AE) of chronic obstructive pulmonary disease (COPD) can benefit greatly from understanding the correlation between disease severity and electrolyte imbalances through the examination of serum sodium and potassium levels in connection to COPD GOLD staging. The findings presented here show that electrolyte problems become more common as chronic obstructive pulmonary disease (COPD) advances, which has important therapeutic consequences for the way patients are managed and treated.

Our research shows that hyponatraemia tends to get worse as COPD progresses. The fact that low sodium levels are only seen in a small percentage of Stage 1 patients implies that the balance of sodium may be reasonably stable in the early stages of the disease. Nevertheless, a large percentage of patients experience hyponatraemia as the disease advances to Stages 2 and 3. Significantly, hyponatraemia is observed in all Stage 4 patients, indicating a significant imbalance in sodium levels in advanced chronic obstructive pulmonary disease.

Hypokalaemia is more common with more severe chronic obstructive pulmonary disease (COPD), according to the correlation between COPD stage and serum potassium levels. Although some individuals may have normal or low potassium levels in the early stages, by Stage 4, hypokalaemia has set in for the vast majority of patients.

This pattern indicates that changes in potassium levels, caused by variables like beta-agonists and maybe diuretics, become more noticeable as the disease progresses. These findings are statistically relevant, as shown by the significant chi-square value (P = 0.031). They are in line with research concerning the effects of medicine and disease progression on potassium levels in chronic diseases, which was discussed by the COPD Guideline Working Group of the South African Thoracic Society

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