Childhood respiratory infections represent one of the leading causes of morbidity and mortality worldwide, particularly among children below five years of age. Recurrent chest infections contribute significantly to repeated hospital admissions, prolonged antibiotic exposure, nutritional deterioration, and impaired growth[1]. Despite advances in vaccination programs, antimicrobial therapy, and supportive care, respiratory infections continue to remain a substantial public health challenge, especially in developing countries.

Malnutrition is closely associated with increased susceptibility to infections and poor clinical outcomes. The relationship between malnutrition and infection is bidirectional; infection increases nutritional requirements through inflammatory responses, fever, and reduced intake, while malnutrition weakens host defense mechanisms and predisposes children to severe and recurrent infections[2]. Protein-energy malnutrition affects both innate and adaptive immunity, resulting in impaired leukocyte function, reduced antibody production, altered cytokine response, and decreased mucosal defense.

Acute malnutrition is commonly classified according to WHO criteria into moderate acute malnutrition (MAM) and severe acute malnutrition (SAM). Moderate acute malnutrition is characterized by weight-for-height Z-score between -3 and -2 standard deviations, whereas severe acute malnutrition is defined by weight-for-height Z-score below -3 standard deviations, MUAC <11.5 cm, or presence of nutritional edema. Children with SAM have a substantially increased risk of severe infections and mortality compared with adequately nourished children[3-4].

The respiratory system is particularly affected by nutritional deficiency. Malnourished children demonstrate reduced respiratory muscle strength, decreased lung compliance, impaired cough reflex, and diminished ability to clear respiratory secretions. These factors contribute to prolonged infection, increased severity of pneumonia, and higher rates of respiratory complications. Furthermore, malnutrition may alter pharmacokinetics of medications and delay response to standard treatment[5].

Recurrent chest infections are frequently observed among children with poor nutritional status. Repeated episodes of infection further worsen nutritional depletion, creating a vicious cycle of infection and malnutrition. Identification of malnutrition at hospital admission provides an opportunity for early nutritional rehabilitation and targeted supportive management[6-7].

Several studies have demonstrated increased mortality and morbidity among malnourished children with pneumonia; however, limited data exist regarding the comparative effect of moderate and severe acute malnutrition on specific clinical outcomes such as duration of hospitalization, oxygen requirement, antibiotic duration, and complications in children with recurrent chest infections[8].

Therefore, this study was conducted to evaluate the impact of moderate and severe acute malnutrition on clinical outcomes among hospitalized children with recurrent chest infections and to determine whether severity of nutritional impairment predicts adverse clinical outcomes.

Aim

To assess the impact of moderate and severe acute malnutrition on clinical outcomes of hospitalized children with recurrent chest infections.

Objectives

1. To determine the prevalence of moderate and severe acute malnutrition among hospitalized children with recurrent chest infections.
2. To compare clinical outcomes among children with normal nutritional status, moderate acute malnutrition, and severe acute malnutrition.
3. To evaluate the association between nutritional status and duration of hospitalization, oxygen requirement, antibiotic duration, and complications.

To assess whether severity of acute malnutrition predicts delayed recovery and increased morbidity in children with recurrent chest infections

Study Design

This prospective observational study was conducted in the Department of Pediatrics at a tertiary care hospital. The study included children hospitalized with recurrent chest infections and assessed the association between nutritional status and clinical outcomes. The study period was conducted over a predefined duration after obtaining approval from the Institutional Ethics Committee. Written informed consent was obtained from parents or legal guardians of all enrolled children before participation.

A total of 105 children hospitalized with recurrent chest infections were included in the study.

Inclusion Criteria

Children fulfilling the following criteria were included

1. Children aged 6 months to 5 years.
2. Hospitalized with clinical diagnosis of recurrent chest infection.
3. History of recurrent respiratory infections (≥2 significant lower respiratory tract infections within 1 year or ≥3 episodes at any time).
4. Children whose parents/guardians provided informed consent.

Exclusion Criteria

Children were excluded if they had:

1. Congenital heart disease or significant cardiac abnormalities.
2. Known chronic lung disease or cystic fibrosis.
3. Congenital immunodeficiency disorders.
4. Neuromuscular disorders affecting respiration.
5. Chronic renal or hepatic disease.
6. Children who had received immunosuppressive therapy.

Clinical Assessment

At admission, detailed demographic and clinical information was recorded, including age, sex, presenting symptoms, previous history of respiratory infections, immunization status, and duration of illness before admission.

Clinical examination included assessment of:

• Respiratory rate
• Oxygen saturation
• Presence of chest retractions
• Wheezing or crepitations
• Fever
• Signs of respiratory distress

Level of consciousness

Signs of dehydration

Laboratory investigations including complete blood count, C-reactive protein, blood culture when clinically indicated, and chest radiography were performed according to standard hospital protocols.

Assessment of Nutritional Status

Nutritional assessment was performed at admission using WHO child growth standards.

Measurements included

• Weight (kg)
• Height/length (cm)
• Weight-for-height Z-score
• Mid-upper arm circumference (MUAC).

Children were categorized into three groups

Group A: Normal Nutritional Status

• Weight-for-height Z-score ≥ -2 SD

Group B: Moderate Acute Malnutrition (MAM)

• Weight-for-height Z-score between -3 and -2 SD
• MUAC 11.5–12.5 cm

Group C: Severe Acute Malnutrition (SAM)

• Weight-for-height Z-score < -3 SD
• MUAC <11.5 cm
• Presence of bilateral nutritional edema

Assessment of Clinical Outcomes

The following outcome parameters were evaluated:

Duration of hospitalization

Number of days from admission until discharge.

Requirement of oxygen therapy

Need for supplemental oxygen during hospitalization.

Duration of antibiotic therapy

Total duration of intravenous/oral antibiotics.

Development of complications

Respiratory failure

Sepsis

Pleural effusion

Treatment failure requiring escalation of therapy

Clinical recovery

Improvement in respiratory symptoms, fever resolution, and ability to maintain oral intake.

Statistical Analysis

Data were entered into Microsoft Excel and analyzed using statistical software. Continuous variables were expressed as mean ± standard deviation, while categorical variables were presented as frequencies and percentages.

Comparison between groups was performed using:

• Chi-square test for categorical variables.
• One-way ANOVA for continuous variables.
• Post-hoc analysis for intergroup comparison.

A p value <0.05 was considered statistically significant.

Table 1: Baseline Demographic and Nutritional Characteristics of Study Participants (n=105)

A total of 105 children hospitalized with recurrent chest infections were included in the study.

Among the study population, 42 (40.0%) children had normal nutritional status, 38 (36.2%) had moderate acute malnutrition, and 25 (23.8%) had severe acute malnutrition.

The mean age of enrolled children was 29.6 ± 14.8 months. Males constituted 62.9% (n=66) and females 37.1% (n=39).

Table 2: Comparison of Clinical Severity Parameters According to Nutritional Status

Severely malnourished children had significantly lower anthropometric measurements and a higher frequency of recurrent infection episodes compared with other groups.

Table 3: Comparison of Hospital Outcomes According to Nutritional Status

Clinical severity markers including respiratory distress, oxygen requirement, inflammatory markers, and ICU admission were significantly higher among children with SAM.

Table 4: Factors Associated with Poor Clinical Outcome in Children with Recurrent Chest Infections

Children with severe acute malnutrition experienced significantly longer hospitalization, prolonged antibiotic requirement, increased treatment escalation, delayed recovery, and higher mortality compared with children having normal nutritional status or moderate acute malnutrition.

Severe acute malnutrition was independently associated with increased risk of poor clinical outcomes. Children with SAM had more than five times higher odds of developing adverse outcomes compared with adequately nourished children

Recurrent chest infections represent a major cause of hospitalization among young children, particularly in regions where malnutrition remains prevalent. The present study evaluated the influence of moderate and severe acute malnutrition on clinical outcomes among 105 hospitalized children with recurrent chest infections[9]. The findings demonstrate that worsening nutritional status is strongly associated with increased disease severity, prolonged treatment requirements, higher complication rates, and delayed recovery.

In this study, 36.2% of children had moderate acute malnutrition and 23.8% had severe acute malnutrition. The high prevalence of acute malnutrition among hospitalized children highlights the close relationship between nutritional deficiency and respiratory morbidity. Previous studies have also reported increased frequency of malnutrition among children admitted with pneumonia and other lower respiratory tract infections[10].

Malnutrition contributes to impaired immune function through multiple mechanisms. Deficiencies of proteins, micronutrients, and essential fatty acids result in impaired cellular immunity, reduced phagocytic activity, decreased complement function, and altered cytokine responses[11]. These abnormalities compromise host defense mechanisms and increase susceptibility to recurrent and severe respiratory infections.

The present study found that children with SAM had significantly higher respiratory distress and oxygen requirements compared with children without malnutrition. This observation may be explained by reduced respiratory muscle strength, impaired lung development, decreased elastic recoil, and ineffective airway clearance associated with severe nutritional deficiency. Similar associations between malnutrition and severe pneumonia have been documented in previous pediatric studies[12].

Duration of hospitalization was significantly prolonged among malnourished children. Children with SAM required an average hospital stay of 10.6 days compared with 5.2 days among children with normal nutritional status. Severe malnutrition delays recovery due to reduced immune response, slower tissue repair, and increased risk of secondary infections. Prolonged antibiotic therapy was also observed among malnourished children, reflecting delayed clinical improvement[13].

The need for intensive supportive care was significantly higher among SAM children. ICU admission occurred more frequently in severely malnourished children, suggesting that nutritional status at admission can serve as an important predictor of disease severity. Early nutritional screening may therefore help identify children requiring closer monitoring[14].

The study demonstrated significantly increased treatment failure and delayed recovery among children with SAM. Severe acute malnutrition increased the odds of poor clinical outcomes by more than five times. This finding emphasizes that nutritional status should be considered an important prognostic marker in children hospitalized with recurrent chest infections.

Moderate acute malnutrition also showed a negative effect on clinical outcomes, although the association was less pronounced compared with SAM. These findings suggest that early identification and management of MAM may prevent progression to severe nutritional deficiency and reduce future infection-related morbidity.

The mortality observed in this study was higher among severely malnourished children. Although the number of deaths was small, the trend supports previous evidence showing that SAM significantly increases the risk of mortality from infectious diseases. Integration of nutritional rehabilitation with standard infection management may improve survival outcomes[15].

Early nutritional assessment using simple anthropometric measurements such as weight-for-height Z-score and MUAC should be incorporated into routine pediatric admission protocols. Nutritional interventions including therapeutic feeding, micronutrient supplementation, and monitoring of feeding tolerance may improve recovery among high-risk children

Moderate and severe acute malnutrition significantly influence clinical outcomes among hospitalized children with recurrent chest infections. Severe acute malnutrition is associated with increased respiratory distress, higher oxygen requirement, prolonged hospitalization, longer antibiotic duration, increased complications, and delayed recovery.

Routine nutritional assessment at hospital admission should be considered essential in children with recurrent chest infections. Early identification and aggressive nutritional management may reduce morbidity, improve treatment response, and decrease adverse outcomes.

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