European Journal of Cardiovascular Medicine

Hyponatraemia, an electrolyte imbalance, affects both community residents and hospitalized patients. Growing older is linked to a higher risk of hyponatraemia, which is a significant risk factor for the condition on its own..[1] Elderly people are more likely to experience acute hyponatraemia symptoms such nausea, vomiting, headaches, stupor, coma, and seizures. Conversely, the signs of chronic hyponatraemia are more subtle and include cognitive decline, abnormalities in gait, falls, poor bone quality (such as osteoporosis), and fractures..[2] Relevant studies have demonstrated an independent relationship between hyponatraemia and an increased risk of mortality, which is connected to an unfavorable prognosis for aged patients.

Because of the aging population, the elderly's increased susceptibility to electrolyte abnormalities, and the higher morbidity associated with hyponatremia in this group, hyponatremia is becoming increasingly significant.

The causes of hyponatremia can be categorized based on the extracellular fluid's volume condition. As previously mentioned, the main component of extracellular fluid (ECF) is salt. Depending on the ECF volume, a patient can be classified as hypovolemic, euvolemic, or hypervolemic..[3]

Increased fluid intake in conjunction with physiological signals that cause the production of vasopressin can result in hyponatremia. Increased vasopressin release may indicate adrenal insufficiency or hypothyroidism. There are two physiological triggers for the release of vasopressin: a reduction in intravascular volume (hypovolemic hyponatremia) or an increase in effective intravascular volume (hypervolemic hyponatremia).

The most prevalent electrolyte imbalance, hyponatremia affects between twenty and thirty-five percent of hospitalized patients.

Hyponatremia is more common in patients recuperating from surgery and in the intensive care unit (ICU).This is particularly common in the elderly due to many variables such multiple chronic conditions, different medicines, and restricted food and drink availability.7. According to a number of studies, hospitalized patients experience hyponatremia at a rate of 12–14% on average, and 1%–2% of them experience severe symptoms. [4]

The research took place at Katihar Medical College and Hospital from July 2022 to December 2023, spanning duration of 1.5 years.

This study comprised 80 patients hospitalized to the medicine ward of the Department of Medicine at Katihar Medical College and Hospital in Katihar, Bihar, who were 60 years old or older and had serum sodium levels below 135 meq/litre.

Study Design: Prospective study

Sample Size: 80 Cases

Duration of Study: One year

Before beginning the inquiry, patients were apprised of the study and given the opportunity to provide their informed permission.

Inclusion Criteria

• Subject age >60 years
• Subject serum sodium <135 meq/litre

Exclusion Criteria

• Subject age <60 years
• Subject serum sodium >135 meq/litre
• Overcorrected hyponatremia
• Patients not willing to participate in the study were excluded from study.

History:-

• History of age and sex
• History of duration of symptoms if present
• Detailed history of drugs used like diuretics.
• History of any coxmorbidities likexhypertension, diabetes,heartxfailure, chronicxliver disease, thyroidxdisorder or chronicxkidney disease.
•  

Data Collection: On the data collecting sheet, we recorded all the usual study information, such as demographics, clinical characteristics, etiology, management, final diagnosis, and clinical details. The next step was to import the data into an Excel spreadsheet.

Statistical Analysis:

For statistical analysis, data were initially entered into a Microsoft Excel spreadsheet and then analyzed using SPSS (version 27.0; SPSS Inc., Chicago, IL, USA) and GraphPad Prism (version 5). Numerical variables were summarized using means and standard deviations, while categorical variables were described with counts and percentages. Two-sample t-tests, which compare the means of independent or unpaired samples, were used to assess differences between groups. Paired t-tests, which account for the correlation between paired observations, offer greater power than unpaired tests. Chi-square tests (χ² tests) were employed to evaluate hypotheses where the sampling distribution of the test statistic follows a chi-squared distribution under the null hypothesis; Pearson's chi-squared test is often referred to simply as the chi-squared test. For comparisons of unpaired proportions, either the chi-square test or Fisher’s exact test was used, depending on the context. To perform t-tests, the relevant formulae for test statistics, which either exactly follow or closely approximate a t-distribution under the null hypothesis, were applied, with specific degrees of freedom indicated for each test. P-values were determined from Student's t-distribution tables. A p-value ≤ 0.05 was considered statistically significant, leading to the rejection of the null hypothesis in favour of the alternative hypothesis.

Table 1: Symptomatology of hyponatremia

Table 2: Severity of hyponatremia

Table 3:Pre-existing illness (n=80)

Figure 1: Etiology of hyponatremia

Figure 2: Pre-existing illness

In the research population, hyponatremia manifests as apathy in 55.0% of cases and lethargy in 30.0%. Thirteen percent of cases show abnormal behavior, and eight percent suffer postural dizziness. In 5.0 percent of cases, seizures are present. although there have been no reports of coma.

Sodium levels below 125 mmol/litre were considered severe in 62.5% of the cases of hyponatremia in the study group. In 21.2% of instances, the sodium level is 130-135 mmol/litre, indicating mild hyponatremia. In 16.3% of cases, the sodium level is 125-129 mmol/litre, indicating moderate hyponatremia.

Among the 80 patients who participated in the study, 36.2% had congestive heart failure, 33.7% had diabetes mellitus, and 30.0% had hypertension, according to the table of pre-existing disorders. Hypothyroidism affects 3.7% of patients, chronic renal disease affects 2.5%, and chronic liver disease affects 5.0%.

Hyponatremia in patients can have several causes, but the most common one is inadequate intake (37.5%), followed by congestive heart failure (35.0%). About a quarter of cases involve vomiting, while about a third have SIADH, or syndrome of inappropriate antidiuretic hormone secretion. Hyperglycemia and diarrhea occur in 6.2% of cases. Hypothyroidism affects 5% of cases and chronic liver disease 2.5% of instances, dehydration 3.7% of cases, and idiopathic 5.0% of cases round out the total.

This study was conducted to determine why older people with hyponatremia are more likely to experience electrolyte problems, as they are all at an elevated risk. This results from the changes that aging brings about in the kidneys as well as the tendency for numerous comorbidities to worsen with age.

In my study, there were 80 patients; 62.5% of them were men and 37.5% were women. The average age was 60.48 participants—59% male and 41% female—participated in a study conducted by xBabaliche et al. In the Jain and Nandyx study, 49% of the sample is made up of men and 49% of women.

Almost all My xinvestigation found that 62.5% of the cases were between the ages of 60 and 70, 20% were between the ages of 71 and 80, 15% were between the ages of 81 and 90, and 2.5% were older than 90.The majority of patients in the Bajaj et al. 53 study were in the age bracket of 60-70 (59.8%), followed by 35.7% in the age group of 70-80 (35.7%).Of the patients studied by Injain and Nandy et al.49, 26 were in the 60–70 age bracket, 50 were in the 71–80 age bracket, and 24 were in the 81–90 age bracket..

Of the 50 male inventors included in my study, 33 (41.3%) fell into the 60-70 age bracket, while 9 (11.2%) belonged to the 71-80 age frame. On the other hand, 21.3% (17 women) were in the 60-70 age bracket, while 8.7% (7) were in the 71-80 age bracket.

In my study, 44 out of 55 instances were asymptomatic when they were first diagnosed. Among the symptoms, 30% (24 cases) exhibit lethargy, 31.3% (25 cases) display abnormal conduct, 8.7% (7) cases exhibit postural dizziness, and 5% (4) patients have seizures.Our patients were not in a coma.Other investigations were also carried out to determine the common clinical aspects, such as,Lethargy, drowsiness, and aberrant behavior were prevalent in the study conducted by Rao et al.[5], and 4% of the patients experienced seizures.While 2.9% of patients exhibited seizures, the most prevalent symptoms reported by mahavir et al.55 were disorientation, headache, tiredness, and nausea. Less than 20% of cases showed any signs of illness.

Out of the 50 cases that were evaluated, 62.5% hadxsevere hyponatremia, 16.3% hadxmoderate hyponatremia, and 21.2% had mild hyponatremia. The results of similar research showed that mild hyponatremia affected 36.5% of the cases (88 out of 105), moderate hyponatremia affected 43.5% of the cases (105 out of 105), and severe hyponatremia affected 20% of the cases (48 out of 105).

Seventeen of the forty-four asymptomatic patients in my studyxhad mild hyponatremia, thirteenxhad moderatexhyponatremia, and fourteenxhad severe hyponatremia.Severexhyponatremia was discovered in all symptomatic patients.

The following conditions were found in my study: hypertension(30%), diabetes(33.7%), congestive heart failure(36.2%), chronic liver disease(5%), hypothyroidism(3.7%), and chronic kidney disease (2.5%).Hypertension and diabetes were prevalent in the Rao et al.[5] investigation, which was similar to others that sought to identify co-morbidities.Note that the most common comorbidities related with maximal studies were hypertension and diabetes.

Thirty percent (24 patients) had normal blood volume, thirty-five Percent (37.5%) were too high, and thirty-two percent (32.5% of the total) were too low, creating hypovolemic hyponatremia. Consequently, hypervolemic hypoosmolar hyponatremia is the most prevalent kind.There were 61% euvolemic, 23% hypervolemic, and 16% hypovolemic cases ofxhyponatremia inxthe research by Rao et al. Babaliche et al.[6] found that 50% of participants were euvolemic, 31% werexhypervolemic, and 17% werexhypovolemic due to hyponatremia.

Twelve patients had hypervolemic hyponatremia, two had hypovolemic hyponatremia, and two had euvolemic hyponatremia out of seventeen instances of moderate hyponatremia in my study. Two instances of euvolemic hyponatremia, nine instances of hypervolemic hyponatremia, and two instances of hypovolemic hyponatremia were among the thirteen cases of mild hyponatremia. Six individuals exhibited hypervolemic hyponatremia, twentyeight patients showed hypovolemic hyponatremia, and sixteen patients exhibited euvolemic hyponatremia out of fiftyxcases of xseverex hyponatremia.

Of the 80 patients analyzed, 50% had low intake, 32.5 percent experienced vomiting, 18.5 percent used diuretics, 14.1 percent had a central nervous system illness, 8.7 percent had diarrhea, and 4.5 percent had pulmonary disease.Poor intake and vomiting were major predisposing factors in similar studies undertaken by Injain and Nandy et al. [7].

In my study, the most common cause was poor intake, accounting for 37.5 % (30) of the cases. Next came heart failure, which accounted for 35% (28) of the cases. Vomiting was observed in 25% (20) of the cases. SIADH was experienced by 18.7 % (15) of the patients. Diarrhea affected 6.2% (5) of the patients. Hypothyroidism was linked to 5%(4) of the cases, dehydration by 3 cases, and chronic liver disease by 2 cases.In order to determine the cause, numerous additional investigations were carried out, such as, The most common causes of renal and gastrointestinal (GI) damage were SIADH (30%), druginduced (24%), renal failure (13%), and other causes. While gastrointestinal issues and renal failure were the subsequent most prevalent causes, inadequate intake accounted for 82.9% of cases in the study by Mahavir et al.

Out of 80 instances, 40 (or 50%) required 3% sodium chloride, 33 (41.2%) were treated with fluid restriction, 30 (37.5%) with diuretics, 10 (8% of the cases) needed normal saline, and 7 (or 10% of the cases) needed potassium supplementation. In a research by Mahavir et al. [8], for example, 34 patients needed 3% NaCl, 39 patients received normal saline, and 28 patients (or 40%) had hydration restriction. The study conducted by Injain and Nandy et al.[9] found that 41% of patients were given 3% NaCl, 26% were given diuretics, and 71% of cases required it. Fluid restriction was enforced in 37% of instances and 9% of patients with sodium chloride excess.

In my investigation, I determined that normalizing sodium takes 1-3 days for 25 instances and 4-7 days for 33 cases. As a result of 4 patients' early deaths (5% of the total), 13 patients were discharged against medical recommendation, and 5 cases were not evaluated. In a study that sought to determine the results of treating hyponatremia, Babaliche et al.[6] found a death rate of 7%.Cases 8 and 53 in Bajaj et al.[10] demonstrate death.

According to the findings of my prospective study, elderly hospitalized patients frequently have hyponatremia, a common electrolyte imbalance.It affects all sexes, albeit males are more prone to suffer it. Those with symptoms had critically low salt levels, even though the majority of patients did not exhibit any. The most often reported symptoms were postural dizziness, abnormal behavior, and lethargy. Patients with co-morbidities of diabetes and hypertension were more likely to experience hyponatremia. Hyponatremia can be caused by a number of things, the most common being insufficient intake; other possible reasons include congestive heart failure, vomiting, and SIADH. My prospective investigation's findings indicate that elderly hospitalized patients frequently have hyponatremia, a common electrolyte imbalance.It happens to both sexes, albeit it seems to affect males more frequently. The majority of patients did not exhibit any symptoms, but those who did had dangerously low salt levels. Postural dizziness, abnormal behavior, and lethargy were the most often reported symptoms. Patients with diabetes and hypertension as co-morbidities were more likely to have hyponatremia. Hyponatremia can result from a number of sources, the most common of which is insufficient intake; other potential causes include congestive heart failure, vomiting, and SIADH.

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