Nutritional status of adolescents undergoing tuberculosis treatment in urban Bangladesh: prevalence and determinants of malnutrition

Introduction

Tuberculosis (TB) is one of the top 10 causes of death worldwide and one of three lethal infectious diseases globally. Despite major global health efforts, TB continues to disproportionately affect low- and middle-income countries (LMICs) [1], 2]. In 2023, an estimated 10.8 million people infected with TB worldwide, including 6.0 million men, 3.6 million women and 1.3 million children [3]. Adolescents (10–19 years), as defined by the World Health Organization (WHO), are often overlooked in TB control programs, despite their increased vulnerability due to biological, social, and systemic factors [2], 3].

Bangladesh ranks among the top 10 countries with the highest TB burden, with an incidence rate of 221 per 100,000 population, thus adolescent face compounded risk [4]. Malnutrition is a known risk factor for poor consequence of TB, weakens immune function, increases susceptibility to infection, delays recovery and increases the risk of treatment failure [5], 6]. Research indicates that malnutrition accounts for around 25 % of all tuberculosis cases, and those with insufficient nutrition experience poorer treatment outcomes with increased mortality rates [7], 8].

Adolescence is a critical period of growth, requiring increased intake of energy, protein, and micronutrients [3]. In resource-limited settings like Bangladesh, food insecurity and poverty frequently lead to undernutrition, especially among adolescents from low-income families [9]. TB in adolescents further complicates this situation, with elevated nutritional demands and reduced intake make situation complex [10], 11]. Nutritional supplementation has demonstrated efficacy in enhancing clinical outcomes in tuberculosis patients, facilitating bacterial clearance, weight gain, and improved health condition [11], 12]. Dhaka is one of the most prevalent TB hub in the world with unplanned urbanization, socio-economic inequalities, and limited access to specialized care. Addressing malnutrition in adolescent tuberculosis patients is crucial for enhancing treatment results, decreasing mortality, and preventing treatment failures [7]. Moreover, around 30 % of adolescents in Bangladesh suffer from malnutrition with poverty, poor access to food, vitamins and minerals, and inadequate healthcare access made situation more challenging [9], 13].

Despite this clear link between TB and poor nutritional outcomes, data on the nutritional status of adolescents with TB in Bangladesh are scarce. Existing studies rarely focused on this age group or use validated clinical assessment tools. The Patient-Generated Subjective Global Assessment (PG-SGA) is a validated tool for evaluating malnutrition in clinical settings, combining patient-reported symptoms with clinician assessments [14]. However, its use in adolescent TB populations in Bangladesh has not been documented. Complementing PG-SGA with WHO recommended BMI-for-age and height-for-age z-scores offers a robust assessment of nutritional status.

This study aims to fill this gap by evaluating the nutritional status of adolescents undergoing TB treatment in Dhaka using PG-SGA and Z scores. The identification of key predictors of malnutrition will also help in integrated, adolescent-responsive TB care strategies.

Methodology

Data collection

Sociodemographic and Clinical Data: Data were collected from 339 adolescent TB patients using a pre-tested, semi-structured questionnaire administered through face-to-face interviews. Information was gathered on sociodemographic characteristics, clinical history, dietary habits, meal frequency, functional status, and access to nutrition-related counseling during TB treatment. Additional information, including TB type and comorbidities, was extracted from medical records for verification [17].

Anthropometric Assessment: Anthropometric measurements were taken following the WHO recommended procedures. Height was measured to the nearest 0.1 cm using a height meter, with participants standing barefoot and maintaining appropriate posture [5], 18]. Weight was recorded to the nearest 0.1 kg using a calibrated digital scale, with participants wearing minimal clothing for accuracy [10], 19]. Body Mass Index (BMI) was calculated using the standard formula: weight (kg) divided by height (m²). To assess malnutrition, BMI-for-age and height-for-age z-scores (HAZ) were calculated using WHO growth standards for adolescents [5], 15], 20]. Based on WHO classification, BMI-for-age z-scores were categorized as follows: < −3 (severe malnutrition), −3 to −2 (moderate malnutrition), −2 to +1 (normal), +1 to +2 (overweight), and > +2 (obese). Height-for-age z-scores were classified to reflect chronic nutritional deficiency: < −3 (severe stunting), −3 to −2 (moderate stunting), −2 to −1 (mild stunting), and ≥ −1 (normal growth) [5], 10], 21].

Patient-Generated Section (PG-SGA Part I): The PG-SGA tool was used as the primary method for nutritional assessment, as it integrates patient-reported symptoms and clinician-observed physical signs [22]. The patient-reported section included information on recent unintentional weight changes, appetite disturbances, current food intake, and the presence of symptoms affecting food consumption, such as nausea, vomiting, or oral ulcers. Respondents also reported their daily functional capabilities and frequency of meals.

Clinician-Assessed Section (PG-SGA Part II): This included evaluation of physical signs of malnutrition such as muscle wasting, subcutaneous fat loss, presence of edema, and assessment of the patient’s overall clinical condition. Clinicians also considered disease-related metabolic stress, including fever, infection severity, and presence of other major illnesses. The cumulative PG-SGA score was then used to categorize nutritional status as well-nourished, moderately malnourished, or severely malnourished, and to determine the need and urgency for nutritional intervention [22].

Data analysis

Data were checked for completeness, consistency and entered into IBM SPSS Statistics version 23 for analysis [4]. Descriptive statistics were used to summarize the sociodemographic and other characteristics of the participants. The nutritional status of participants was assessed using both PG-SGA and z-scores, allowing for cross-validation of results. Chi-square tests were performed to identify associations between categorical variables and malnutrition status. Factors that showed significant associations in bivariate analyses were included in logistic regression model to identify independent predictors of malnutrition. Adjusted odds ratios (OR) with 95 % confidence intervals (CI) were calculated to assess the strength of associations, and a p-value of less than 0.05 was considered statistically significant.

Ethical considerations

Ethical approval for this study was obtained from the Institutional Review Board (IRB) of the National Institute of Preventive and Social Medicine (NIPSOM) [Memo No: NIPSOM/IRB/2023/06(a), dated 22 October 2023]. Informed consent was obtained from the parents or legal guardians of all adolescent participants. In addition, assent was obtained from the adolescents themselves to ensure voluntary and informed participation.

Results

This study included 339 adolescents aged 10–19 years (mean age: 15.71 ± 2.72), with nearly half (49.9 %) in the 17–19 age group. Females comprised 58.1 % of the sample, and 99.4 % of respondents identified as Muslim. Most participants resided in urban areas (63.4 %), were unmarried (88.2 %), and lived in nuclear families (88.2 %). Regarding education, 62.8 % had attained secondary education, and 74 % were currently enrolled in school. Fathers primarily had no formal (29.5 %) or secondary (28 %) education, while 32.2 % of mothers had completed secondary education. Most fathers were involved in business (35.7 %), and the majority of mothers were homemakers (84.7 %). The average monthly household income was BDT 25,772.86 ± 18,031.16, with 30.7 % earning between BDT 20,001 and 30,000. While 37.5 % of families reported having a smoker, only 2.9 % of respondents personally used tobacco (Table 1).

Eating difficulties during treatment were reported by 45.4 % of participants, with appetite loss being the most common (23.0 %), followed by nausea (5.9 %) and mouth ulcers (3.5 %). Some adolescents experienced multiple symptoms simultaneously, such as nausea with appetite loss (8.3 %) or a combination of nausea, ulcers, and appetite loss (1.8 %). Although 52.8 % received nutrition-related information during treatment, only 1.8 % reported receiving comprehensive nutritional care, indicating a major service gap. Most participants (94.1 %) maintained normal functional status, while 4.7 % required mobility assistance and 1.2 % were bedridden (Table 2).

The mean BMI was 17.89 ± 3.68. Based on BMI, 59.3 % of adolescents were underweight, 37.8 % had normal weight, and 2.9 % were overweight. According to PG-SGA scores, 14 % were severely malnourished, which was consistent with BMI-for-age z-scores identifying 14.2 % with severe malnutrition and 21.2 % with moderate malnutrition. Height-for-age z-scores (HAZ) revealed 6.5 % were severely stunted, 19.5 % moderately stunted, and 37.8 % mildly stunted (Figure 1).

Figure 1:

Status of nutritional status indicators: (a) PG-SGA category, (b) BMI (height/m²), (c) BMI-for-age: z-score (nutrition), (d) height-for-age: z-score (stunting).

We have identified a significant association between acquisition of nutritional information and good nutritional status, with a p-value of 0.001. Likewise, daily functional status significantly influenced nutritional outcomes (p-value=0.001). The daily meal consumption was another significant factor, exhibiting a p-value of 0.007. We identified a substantial correlation (p-value=0.000) between eating disorders and malnutrition, such as appetite loss or related concerns (Table 3). Table 4 presents the results of logistic regression analysis, where nutritional counseling demonstrated a protective trend against malnutrition (AOR=0.620, p=0.063), while not statistically significant. Males had a lower likelihood of malnutrition than females (AOR=0.514, p=0.009). Moreover, those who consumed three meals daily exhibited a significantly elevated risk of malnutrition compared to those who consumed four meals (AOR=2.692, p=0.009). Significant comorbidities (AOR=3.675, p=0.014) and eating disorders (AOR=3.409, p<0.001) were robust predictors of malnutrition. Individuals diagnosed with Type I tuberculosis demonstrated a markedly elevated risk of malnutrition (AOR=2.574, p<0.001), underscoring the necessity for focused nutritional interventions.

Discussion

This study provides an assessment of the nutritional status of adolescents undergoing TB treatment in urban Bangladesh, revealing a high burden of malnutrition despite relatively favorable educational and urban living conditions. Using both the PG-SGA and z-scores, we observed close to similar findings, found about 14 % adolescents were severely malnourished and another 40 % were moderately malnourished according to PG-SGA. This high malnutrition prevalence highlighting risk on adolescents’ physical growth, immune function, and recovery of TB [23]. This is expected because, the previous studies in Bangladesh also showed a high prevalence of malnutrition among general people in Bangladesh [24]. Our result is particularly concerning, as the participants are mostly urban with relatively high rates of school enrollment and access to healthcare facilities, which indicating the limitation of current services to prevent undernutrition during TB care. Height-for-age z-scores (HAZ) revealed a high prevalence of stunting, with 6.5 % severely stunted, 19.5 % moderately stunted, and 37.8 % mildly stunted. Only 36.3 % had a normal height-for-age, also indicating widespread undernutrition [25]. These findings align with regional studies that report similar rates of stunting among Bangladeshi adolescents [26]. Stunting is often associated with childhood malnutrition, leading to impaired cognitive development, physical limitations, and long-term health risks [27].

A major concern identified was the gap between receiving nutritional information and accessing actual nutrition services. While over half of the adolescents received some form of dietary counseling, only 1.8 % received comprehensive nutrition support. This indicates a critical disconnect between education and service provision, consistent with findings from other adolescent health studies in Bangladesh, which report limited integration of nutrition into TB care pathways [28], 29]. Many health programs focus on general health education but fail to provide specialized services, such as dietary counseling and follow-up care. Islam et al. emphasize the need to integrate nutrition care into adolescent health services, especially in rural and underserved areas [29]. These indicates that, nutritional program should be effectively implemented in the TB care as there is an overall poor status.

Eating difficulties, especially appetite loss, were prevalent and strongly associated with malnutrition (OR=3.409, p<0.001). These symptoms create problem in nutrient intake during the treatment phase, indicating the need for early identification and management of nutrition-impact symptoms. The number of meals consumed per day was another key predictor, as adolescents consuming fewer than four meals daily had nearly three times the odds of being malnourished. These findings align with regional research emphasizing the protective role of meal frequency in adolescent nutrition [8]. Gender-based disparities in nutritional outcomes were also evident. Females were more likely to be moderately or severely malnourished than males, and logistic regression confirmed that being male was protective (AOR=0.514, p=0.01). This finding may reflect socio-cultural inequalities in intra-household food distribution, care-seeking behavior, and gendered health vulnerabilities documented in South Asian contexts [7], 18]. Comorbidities also identified as a strong determinant of malnutrition (AOR=3.675, p=0.01), as did the severity of TB patients with Type I TB were significantly more likely to be malnourished (OR=2.574, p<0.01). These associations support the understanding that both disease burden and physiological stress contribute to malnutrition, indicating the need for differentiated care models.

Dietary patterns revealed that 79.6 % of adolescents consumed three meals a day, which is typical for South Asia, particularly in urban settings [30]. Rural areas, in particular, tend to have lower meal frequencies due to lower incomes and agricultural work schedules [31]. Cereals were the most frequently consumed food group, with 97.1 % of participants eating them more than three times a week, reflecting the prevalence of rice and wheat-based foods in South Asian diets. These calorie-dense foods may vary in nutritional quality depending on preparation methods [32]. Dairy consumption was lower, with 44.5 % of participants consuming milk and dairy products more than three times a week, which is lower than consumption rates in regions where dairy is a more regular part of adolescent diets [33]. These highlights a significant gap in the provision of comprehensive nutrition services for adolescents, an issue that has been widely discussed in studies on adolescent healthcare in Bangladesh and South Asia [28].

Most adolescents (94.1 %) in this study maintained an active daily functional status, with only 4.7 % requiring mobility assistance and 1.2 % being bedridden. These results suggest that the majority of participants were in relatively good overall health, despite facing some nutritional challenges. The BMI distribution is concerning, with 59.3 % of adolescents categorized as underweight, 37.8 % normal weight, and only 2.9 % overweight or obese. In terms of education, 62.8 % of participants had attained secondary education, and 74 % were currently enrolled in school, aligning with national trends that show significant progress in adolescent education in Bangladesh. Secondary school enrollment rates have steadily increased in recent years, with 86 % of girls and 85 % of boys enrolled in urban areas [26]. Despite this progress, 29.5 % of participants reported that their fathers had no formal education, consistent with studies on rural and low-income urban families [27].

Limitations: This study has several limitations and first one is the study design. The cross-sectional nature of the study restricts causal inference. While significant associations between malnutrition and factors such as gender, comorbidities, meal frequency, and eating difficulties were identified, temporal relationships cannot be established. Second, the study was conducted only in urban tertiary hospitals in Dhaka, which may limit the generalizability of the findings to adolescents living in rural or hard-to-reach areas, where nutritional and healthcare access patterns is different. Although the use of the PG-SGA is a validated tool, it is partially reliant on self-reported measures, including weight change, dietary intake, and symptom recall, which are subject to recall bias and social desirability bias, particularly in adolescent populations. The use of convenience sampling introduces potential selection bias. Adolescents who were more health-conscious or who had caregivers available to accompany them to the hospital may have been more likely to participate. Despite these limitations, this study adds valuable evidence to the adolescent nutrition in the context of tuberculosis in LMICs and highlights gaps in service delivery, warrant urgent attention.

Conclusions

This study reveals a high burden of malnutrition among adolescents undergoing tuberculosis treatment, with over half classified as moderately or severely malnourished. The consistent findings from both PG-SGA and anthropometric assessments indicates the reliability of our findings. Service gaps were evident, particularly the low provision of comprehensive nutritional care despite widespread need. These findings highlight the urgent necessity of integrating routine nutritional screening and support into adolescent TB programs. Early identification of nutritional risk combined with dietary counseling, symptom management, and meal support, could substantially improve treatment outcomes. Special attention should also be directed toward TB patients with comorbid conditions. Strengthening multisectoral collaboration between TB, nutrition, and adolescent health services is essential for addressing the dual burden of disease and undernutrition in this high-risk population.