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| ORIGINAL ARTICLE |
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| Year : 2020 | Volume
: 64
| Issue : 4 | Page : 368-373 |
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Risk factors for pneumonia mortality in under-five children in a tertiary care hospital of Darjeeling district of West Bengal: A prospective case–control study
Sumanta Chakraborty1, Abhijit Mukherjee2, Sharmistha Bhattacherjee2, Rahul Majumdar3, Mridula Chatterjee4, Samir Dasgupta5
1 Demonstrator, Department of Community Medicine, Bankura Sammilani Medical College, Bankura, West Bengal, India
2 Assistant Professor, Department of Community Medicine, North Bengal Medical College, Darjeeling, West Bengal, India
3 Assistant Professor, Department of Paediatrics, North Bengal Medical College, Darjeeling, West Bengal, India
4 Ex-Professor, Department of Paediatrics, North Bengal Medical College, Darjeeling, West Bengal, India
5 Professor, Department of Community Medicine, North Bengal Medical College, Darjeeling, West Bengal, India
| Date of Submission | 17-Feb-2019 |
| Date of Decision | 11-May-2019 |
| Date of Acceptance | 24-Jul-2020 |
| Date of Web Publication | 11-Dec-2020 |
Correspondence Address:
Abhijit Mukherjee
Department of Community Medicine, North Bengal Medical College, Sushrutanagar, Darjeeling - 734 012, West Bengal
India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/ijph.IJPH_79_19
 Abstract | | |
Background: Among children admitted with pneumonia, several modifiable predictors have been identified for deaths in children in hospitals. Despite the presence of a several national programs designed to address most of the risk factors directly or indirectly it is surprising that they continue to be common in children with pneumonia. Objectives: The objective is to determine the risk factors for pneumonia mortality in under-five children in a tertiary care hospital of Darjeeling district of West Bengal. Methods: An analytical study with case–control design was conducted between May 2016 and October 2017. Children aged 2–59 months admitted with the diagnosis of pneumonia were followed up after admission and who died were recruited as cases and two consecutive age- and sex-matched controls were recruited among children who were declared cured and discharged. A total of 95 cases and 190 controls were studied and the risk factors were compared in the pair matched groups by the conditional logistic regression. Results: Factors influencing childhood pneumonia mortality were severely underweight (adjusted odds ratio [AOR]: 3.66 [1.28,10.46]) unimmunized child (AOR 4.18 [1.53, 11.41]), lack of exclusive breast feeding (AOR: 3.12 [1.23, 7.91]), past history of diarrhea or acute respiratory infection in the last 3 months (AOR: 7.27 [3.68, 14.36]), hypoxemia on admission (AOR: 2.53 [1.14, 5.61]), sub-center as the first contact health facility (AOR: 6.49 [2.15, 19.67]), and antibiotic not received at first contact (AOR: 3.18 [1.36, 7.43]). Conclusions: Most of the risk factors for death in children between 6 and 59 months of age are directly or indirectly related to health service delivery and can be ameliorated through proper structural and administrative measures.
Keywords: Pneumonia, prospective case–control study, risk factors, under-five children
How to cite this article:
Chakraborty S, Mukherjee A, Bhattacherjee S, Majumdar R, Chatterjee M, Dasgupta S. Risk factors for pneumonia mortality in under-five children in a tertiary care hospital of Darjeeling district of West Bengal: A prospective case–control study. Indian J Public Health 2020;64:368-73 |
How to cite this URL:
Chakraborty S, Mukherjee A, Bhattacherjee S, Majumdar R, Chatterjee M, Dasgupta S. Risk factors for pneumonia mortality in under-five children in a tertiary care hospital of Darjeeling district of West Bengal: A prospective case–control study. Indian J Public Health [serial online] 2020 [cited 2023 Mar 22];64:368-73. Available from: https://www.ijph.in/text.asp?2020/64/4/368/303107 |
| Introduction | |  |
Pneumonia is a major public health concern because of its impact on under-five morbidity and mortality. Pneumonia along with diarrhea are estimated to cause 1.7 million deaths each year. It kills more children than any other illnesses, more than malaria, measles, and AIDS combined and had contributed to 15% of under-five deaths globally in 2015.[1] In 2008, the Child Health Epidemiology Reference Group predicted that India contributed around 43 million pneumonia cases (23% of the world's total) and estimated an incidence of 0.37 episodes per child-year for clinical pneumonia based on estimates from mathematical models.[2]
An increasing number of these children with pneumonia, nowadays, are being referred to the hospitals for treatment from the community. Despite this, deaths from pneumonia remain unacceptably high even in tertiary care settings. Several predictors such as low birth weight, under-nutrition, the presence of anemia, lack of exclusive breast feeding, and immunization have been identified that are responsible for pneumonia deaths in children in hospitals.[3],[4],[5]
In the presence of a myriad of national programs designed to address most of the risk factors directly or indirectly, it is surprising that these still continue to be common in children with pneumonia. For example, under the Integrated Child Development Services (ICDS) Scheme and Integrated Management of Neonatal and Childhood Illness (IMNCI) both the ICDS workers and the Auxiliary Nurse Midwives (ANMs) should act synergistically to identify low birth weight babies in the general population and arrange supplementary nutrition for them.[6] In addition, nutritional supplementations and Iron therapy in children under the National Iron Plus Initiative should address the issues of anemia in children.[7]
Thereby, the study was conducted with the aim of generating data on risk factors for pneumonia mortality in under-five children in a tertiary care hospital of West Bengal catering to patients from hilly and difficult terrains, tea garden workers, tribal population, and also to the patients from adjoining districts, States of Sikkim, Bihar, Assam as well as from Nepal, Bhutan, and Bangladesh.
| Materials and Methods | | |
Study type and design
The present study was an analytical epidemiological study with prospective case–control design.
Study setting
The study was conducted at the department of Paediatrics, North Bengal Medical College Hospital (NBMCH), Darjeeling, a tertiary care teaching hospital with undergraduate and postgraduate medical courses. The pediatric ward at NBMCH has an attached Sick new-born care unit, a pediatric intensive care unit (PICU) and a neonatal intensive care unit (NICU). The hospital also has a 24-h emergency where patients can be treated or admitted. The pediatric outpatient department caters to an average of 200 children daily.
Study population
Children in the age group of 2–59 months diagnosed as pneumonia, by the attending physician, from the outpatient or emergency department of the hospital, based on clinical features, chest X-ray or laboratory reports, are admitted to the pediatric wards between May 2016 and October 2017, were included in the present study. They were subsequently reclassified by the researchers as no pneumonia, pneumonia, or severe pneumonia as per the IMNCI guidelines.[6] Children having cleft lip and cleft palate and diagnosed as foreign body aspiration pneumonia were excluded from the study.
Selection of cases
The children were identified from their admission records and then their parents or guardians were interviewed and the child was examined. Next, the child was followed up for their outcome, those who died of pneumonia were recruited as cases. In cases where the child had died or were discharged before collection of relevant investigational reports, those were collected by the investigator from the respective departments for research purposes.
Selection of controls
Those children diagnosed with pneumonia, who were discharged as cured by the treating physician, were regarded as control.
Matching
Cases consisted of children 2–59 months of age diagnosed with pneumonia by the treating physician and subsequently died of it. Consecutive age (in completed months) and sex matched control were recruited at the allocation ratio of 1:2 from children admitted to pediatrics ward with pneumonia and declared cured by the treating physician, preferably in the same month or within the next 7 days of admission as the case. Pair matching was done so that each group consists of 1 case and its 2 corresponding age- and sex-matched controls for analysis using the conditional logistic regression.
Measurement of exposure variables
Diagnosis and grading of weight for age, pallor, exclusive breast feeding, IMNCI danger signs, and severity of pneumonia were based on the standard IMNCI guidelines.[6]
The immunization status of the child was described based on the definitions in the national immunization schedule.[8]
Exclusive breast feeding
Only mother's milk and nothing except that till 6 months of age was exclusive breast feeding.
First contacted health facility
The first treatment received from after onset of illness. Primary health center, block primary health center, state general hospitals, district or subdivisional hospitals were grouped as government health-care set-ups and those seeking care from private practitioners, medicine shops, dispensaries, and nursing homes were considered as private health set-ups for the study and those receiving the treatment from the ANM at the nearest subcenter or subhealth post was considered separately.
First dose antibiotic
The child had been diagnosed as pneumonia and received any antibiotic treatment at primary and secondary care level of treatment was noted.
Sample size and sampling techniques
The sample size was estimated using the 2:1 controls per case formula.[9],[10] The anticipated odds ratio (OR) between controls and cases was taken as 3. Of the determinants used in the study, the value of the variable with the lowest prevalence rate (malnutrition as 12.9%) in the control group, obtained from a similar study in Chennai, was used to calculate the sample size.[3] The variable with the lowest prevalence rate in the control group was used so as to obtain the maximum sample size. Considering a power of 80% and a 5% alpha error, the sample size was determined to be 79 cases and 158 controls. However, the final sample included 95 cases and 190 controls, although we achieved our sample size, we preferred to continue the data collection for a full allotted period of 1 year.
Study tools and study techniques
The study tool consisted of a predesigned, pretested schedule for recording sociodemographic data of the participants, the WHO growth charts, relevant records/registers of study participants (birth records, immunization records) and treatment cards/prescriptions. For children treated by nonqualified physicians prior to admission to the hospital, due to the lack of prescriptions, declaration of the parents/caregivers regarding antibiotic use was reported. Clinical examination of the child was done by stethoscope, digital watch, pulse oxymeter, etc., and anthropometric measurement was done by infantometer, weighing scale. Weight for age of the child was plotted in the WHO growth chart to ascertain the nutritional status.
The study techniques included interview of parents/guardian, clinical, and anthropometric examination of the child and reviewing of records. Baseline data of all children were recorded at admission. Following death of a child, the patient was included as a case and age- and sex-matched controls were selected from among the recorded data of the children at admission.
Statistical methods
All data were entered into the IBM Corp. Released 2011. IBM SPSS Statistics for Windows, Version 20.0 (Armonk, NY: IBM Corp.) and checked for accuracy. Inconsistencies were resolved by comparing with the raw data. Conditional univariate and multivariate logistic regression using death due to pneumonia as the outcome variable were done. The association of the risk factors was determined at the individual level and after adjustment using the OR and the 95% confidence intervals (CIs). All hypothesis testing were two tailed and P ≤ 0.05 was considered statistically significant.
Ethical considerations
The study was conducted after the approval of the Institutional Ethics Committee of North Bengal Medical College, Darjeeling vide letter number PCM/2015-16/603I dated 0.12.2015. Informed consent was obtained for all the study participants.
| Results | | |
Recruitment of cases and controls is shown in [Figure 1]. Between May 2016 and April 2017 there were 1896 admissions of children with pneumonia at the Paediatric Inpatient Department (Paediatrics ward/NICU/PICU) of the North Bengal Medical College and Hospitals. Of them, 95 were recruited as cases and 190 were recruited as controls. The mean and standard deviation of age was 15.64 ± 16.2 months in cases and 15.23 ± 15.8 months in controls. Statistical analysis does not show a significant difference between the means in the two groups. There were 34.7% females among both cases and controls. | Figure 1: Flow chart showing recruitment of cases and controls. *Patients refused admission, nonavailability of beds. #Patients with diagnoses of asthma, foreign body aspiration, bronchiolitis, cough and cold, tuberculosis, etc.
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The maximum number of pneumonia deaths in under-five children were in the age group of 2 months to 6 months of age, i.e., 36.8%, followed by those children between 24 months and 59 months, i.e., 25.3% [Table 1].
Risk factors of pneumonia mortality
On bivariate analysis, following factors were found to be significantly associated with childhood pneumonia mortality as shown in [Table 2]: severely underweight child (OR: 4.71; 95% CI: 2.56, 8.65), child with severe pallor (OR: 5.72; 95% CI: 2.82, 11.61) unimmunized child (OR: 6.32; 95% CI: 2.75, 14.55), lack of exclusive breast feeding (OR: 2.55; 95% CI: 1.33, 4.87), history of diarrhea, or acute respiratory infection (ARI) in the past 3 months (OR: 8.89; 95% CI: 4.64, 17.03), hypoxemia on admission (OR: 2.96; 95% CI: 1.69, 5.19), subcenter as the first contact health facility (OR: 7.99; 95% CI: 3.47, 18.46), and antibiotic not received at first contact (OR: 3.09; 95% CI: 1.76, 5.42).
After adjustment by multivariable analysis, the following factors were seen to be significantly associated with mortality, severely underweight child (adjusted OR [AOR]: 3.66; 95% CI: 1.28, 10.46), unimmunized child (AOR: 4.18; 95% CI: 1.53, 11.41), lack of exclusive breast feeding (AOR: 3.12; 95% CI: 1.23, 7.91), past history of diarrhea or ARI in the last 3 months (AOR: 7.27; 95% CI: 3.68, 14.36), hypoxemia on admission (AOR: 2.53; 95% CI: 1.14, 5.61), subcenter as the first contact health facility (AOR: 6.49; 95% CI: 2.15, 19.67), and antibiotic not received at first contact (AOR: 3.18; 95% CI: 1.36, 7.43).
After controlling for the predictors, the model explained between 3.34% (Cox and Snell R2) and 5.4% (Nagelkerke R2) of the variance of pneumonia mortality in the study subjects. It can be inferred that the model fitted well from nonsignificant (P = 0.738) Hosmer and Lemeshow statistic.
| Discussion | | |
The present study identifies several risk factors such as malnutrition, nonimmunization, lack of exclusive breast feeding, history of diarrhea or ARI in the preceding 3 months, hypoxemia on admission, type of first contact health facility and institution of antibiotic at first contact and time to initiation of treatment as predictors of mortality in children admitted to the North Bengal Medical College pediatric unit with a diagnosis of community acquired pneumonia.
Malnutrition has consistently been seen to be an important predictor of pneumonia mortality in children contributing to a third of all childhood deaths.[11],[12],[13] It decreases the ventilatory drive, depress respiratory muscle function, cause alterations of lung parenchyma and depress lung defense mechanism, all of which can singly or in combination lead to pneumonia. In addition, malnutrition can lead to the development of other predictors like anemia which has been seen to be a significant predictor of childhood pneumonia mortality even after adjustments for other factors. Chronic malnutrition damages the immune system in children leading to increased vulnerability and severity of the pneumonia. Malnutrition can proximally be linked to other significant predictors of mortality like the of lack of exclusive breast feeding or a history of ARI/diarrhea in the preceding months.[5]
The protective effects of breastfeeding against pneumonia incidence, prevalence, hospitalizations, and mortality have confirmed the importance of breastfeeding.[5] It is a key life intervention during the first 23 months of life in reducing pneumonia morbidity and mortality, even after adjusting for confounders like socioeconomic class which tends to increase the duration of breast feeding. The absence of exclusive breast feeding has been seen to increase pneumonia mortality in hospital-based studies on risk factors for pneumonia in under 5 children from India.[5],[14]
Immunization has long been regarded as an important predictor of pneumonia mortality.[15],[16] Immunization against Haemophilus influenza type b (Hib) and Streptococcus pneumonia (pneumococcus), two of the most common pathogens of childhood pneumonia, is directly responsible for a decrease in childhood deaths by decreasing the total number of cases of pneumonias caused by the organisms. Hib, although currently included in the national immunization schedule, was not included in it at the time of the study, while the pneumococcal vaccine is yet to be included under the schedule. Thereby, the reasons for the significant decrease in childhood pneumonia deaths among vaccinated children compared to the nonvaccinated ones need further research. Pneumonia is the most common complication of both pertussis and measles. The frequency of pneumonia among patients with measles is about 2%–27% in the community and 16%–77% in hospital settings.[17] Immunization against DPT and measles, should, at least theoretically, decrease the total number of deaths due to pneumonia secondary to pertussis and measles.[18] However, in their study on rural preschool children, Srivastava et al. failed to find any significant association with pneumonia.[19]
Availability of vaccines at the peripheral levels is indicative of the availability of health-care services at these levels; hence, the higher levels of immunization can be attributed to higher accessibility of health-care services in the area facilitating prompt treatment and referral. Mothers utilizing immunization services will be better aware of health care facilities and will probably seek early consultations for illness in their children, decreasing the chances of the development of serious disease.[12]
Hypoxemia has been reported to be a common and potentially lethal complication of acute lower respiratory infection with 3–4 times increased risk of death in children.[20],[21],[22],[23] The risk of hypoxemia varies with the severity of the disease,[24] which, in turn, depends to a large extent on the time taken between the first appearance of symptoms and care seeking.[25] The situation becomes a little more complex with the type of care seeking facility attended by the patient because of the differences in facilities and un-standardized nature of treatment of cases. Facilities for detecting arterial oxygen saturation, one of the major factors linked to pneumonia outcome, are not available at the subcenters and precious time may be lost in the institution of supplemental oxygen, which has been shown to be effective in preventing pneumonia deaths in these children.[22] Early goal directed oxygen supplementation may prevent deaths from sepsis which is also a fatal outcome of childhood pneumonia.[26] Floyd et al.'s in their large simulation, study estimated that systematic pulse oximetry could prevent about 150,000 deaths from pneumonia globally annually.[23] There is a therefore an urgent need to increase the availability of pulse oximeters for easy and early diagnosis of hypoxia and immediate institution of supplemental oxygen in primary care health facilities in developing countries like India.
Lack of awareness about the signs and symptoms of community acquired pneumonia and its danger signs cause patient/caregiver related delays in seeking qualified care. To add to this, health system delays in diagnosis, treatment initiation, or referral in appropriate cases results in delayed referral of complicated cases.[27] Prereferral antibiotic use has been seen to be associated with significant decreases in childhood mortality[28] and has been included in the IMNCI recommendations in India. The trained ANM at the subcenter, usually the first contact health-care provider, is entrusted with the task of administering the first dose of antibiotic to the child before referral. Despite the recommendations, the present study did not find any child that had received (injectable) antibiotic injections at the subcenter. Since, prereferral antibiotic administration, from other sources, is seen in the present study to increase the chances of survival from pneumonia, a more concerted effort to stick to the guidelines rigorously would decrease large number of childhood pneumonia deaths.
The admission protocol for pneumonia affected children was not well defined in the institute, so subjective bias by admitting physician could not be ruled out. In addition, chance of recall bias of care givers cannot be eliminated. Attempts were made to review records, especially regarding immunization wherever possible to take care of this issue. The authors also regret their inability to provide the readers with data regarding follow-up of the children after discharge.
| Conclusion | | |
Most of these risk factors found in the present study can be seen to be directly related to health service delivery issues and can be ameliorated through proper structural and administrative measures. Children at risk of acquiring pneumonia and at risk of death from pneumonia can be easily identified and the risk factors addressed through the current national programs.
Financial support and sponsorship
This study was funded by ICMR for MD thesis grant for Dr. Sumanta Chakraborty vide letter number 3/2/March – 2016/PG- Thesis HRD (5) dated 29.03.2016.
Conflicts of interest
There are no conflicts of interest.
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[Figure 1]
[Table 1], [Table 2]
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