Hemoglobin level as a risk factor for lower respiratory tract infections
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《美国医学杂志》
Department of Pediatrics, Amrita Institute of Medical Sciences and Research Centre, Kochi, Kerala, India
Abstract
Objective. This prospective study was conducted to evaluate the role of hemoglobin level, as a risk factor for Lower Respiratory Tract Infections in children (LRTI). Methods. 100 children who came to the outpatient department for LRTI were included in the study. Age and sex-matched 100children, not having any respiratory illness, were taken as control. They were subjected to complete blood count (CBC) ,C-reactive protein estimation (CRP), Mantoux test, and X-ray chest. Peripheral smear, serum ferritin and serum iron binding capacity were done for all anemic children. Results. Radiological evidence of pneumonia was present in 63 children(63%).Hyper inflated lungs were seen in 27 (27%). Mantoux was positive in 22 children (22%) of study group and none among control group. CRP > 6mg/L was noted in 45 children (45%) of study group and 14 (14%) of control group. Seventy four of study group (74 %) and 33 of control group (33%) had anemia. Of the anemic children, 60(60%) had iron deficiency,10 (10%) chronic inflammation and 4 (4%) had hemolytic anemia. These values were 30(30%), 2(2%) and1(1%)respectively for control group. Low hemoglobin level due to whatever etiology, was a risk factor (p=0.000). Conclusion. Anemic children were 5.75 times more susceptible to LRTI compared to the control group. Prevention of anemia, due to whatever etiology, will reduce the incidence of LRTI
Keywords: Lower respiratory tract infection; Hemoglobin level
Lower respiratory tract infections (LRTI) include all infections of the lungs and the large airways below the larynx.[1] On an average, children below 5 years of age suffer about 5-6 episodes of LRTI per year.[2]
A child was considered anemic, if the hemoglobin (Hb) level was below 11g/dL.[3] Lower respiratory tract infections associated with anemia occur more commonly in children than in adults. But low hemoglobin level due to whatever etiology per se, as a risk factor for developing LRTI has not been fully evaluated. Hence this prospective study was conducted for assessing low hemoglobin level, as a risk factor for developing LRTI in children.
Material and Methods
This prospective study was conducted in 100 children who attended the out patient unit of Department of Pediatrics, Amrita Institute of Medical Sciences and Research Centre Kochi, during the period of one year from March 2003 to February 2004. Pneumonia was diagnosed by symptoms and clinical signs.[4] Children with the following criteria were exempted from this study: (i) Congenital malformations of chest wall; (ii) Having severe systemic illness; (iii) Protein Energy Malnutrition (PEM > Grade III as per Indian Academy of Pediatrics (IAP) classification .[5]
Weight and height were recorded for all children to assess the nutritional status. The following investigations were done in all cases: Complete Blood Count (CBC), C reactive protein estimation (CRP), Mantoux test and X-ray chest. Peripheral smear, serum ferritin and serum iron binding capacity were done in all anemic children.
Mantoux test was taken as positive with an induration of 10 mm or more .X-ray chest was taken by conventional methods and interpreted as described.[6]
Age and sex-matched 100 children, attending the pediatric outpatient department for check-up with complaints of illness other than LRTI were randomly selected as control.
Statistical Analysis
Numerical variables were reported in terms of mean and standard deviation. Categorical variables were reported in terms of numbers and percentages.
Association of each of the categorical variable with response variable was assessed by Chi-square test and the strength of their association was computed by unadjusted odds ratio. Variables showing statistically significant association in univariate analysis with the outcome variable up to p=0.25 were considered as risk factor. Only those variables were subjected to multivariate analysis. Logistic regression technique was used to find the risk factor for LRTI. In multivariate analysis, variables showing p value less than 0.05 was considered to be statistically significant.
Results
Age group of children varied from 9-months to 16 years. CRP was more than 6 mg/L, in 45 children (45%) in the study group 14(14%) in the control group. Mantoux test was positive for 22 (22%) among study group and none in control group. Radiological evidence of pneumonia was present in 63(63%), and hyperinflation of lung fields in 27 (27%) among study group. Despite clinical signs, X-ray chest were normal in 10 cases (10%). In both groups, age was not found as a significant factor affecting the result. (p=0.38, and 0.47 respectively for study group and control) seventy four children (74%)in the study group and 33 (33%)of control were anemic. Among the anemic children in study group,60(60%) had iron deficiency anemia (IDA),10 (10%) had anemia of chronic infection(ACI) and the rest 4(4%) had hemolytic anemia(HA). Thirty three(33%) children in controls were anemic and 30(30%) out of them had IDA and 2(2%) had ACI and the rest one(1%) was suffering from HA. Descriptive data regarding age, sex , mean and standard deviation of hemoglobin, white blood cell count(WBC) absolute neutrophil ( ANC) and eosinophil count(AEC) are shown in table1.
Fifty eight cases (58%) in the study group had a history of wheeze. Forty (40%) gave a positive family history of asthma.
Discussion
Several risk factors for developing LRTI had been reported in different studies. Baskaran et al in a study of 43 children between 3-5 years had found 83 % with pneumonia had hemoglobin less than 11 g/dL. [7]
In another study of iron deficiency anemia and respiratory infection by De-Silva A et al, an over all prevalence of anemia was found in 52.6%.[8] He concluded that iron treatment significantly reduced the morbidity of even children with URTI.
Attending a day care center was reported as the most important risk factor for respiratory tract infections in children aged 2-5 years.[9] In a community based study of 288 children, risk factors for LRTI noted were being a boy, attending a child care center, exposing to passive smoking and sharing a bed room with children aged 0-5 years. [10]
Few reports are available in literature regarding the role of low hemoglobin level per se, as a risk factor for developing LRTI. We have found that reduced hemoglobin level due to whatever etiology was a significant risk factor for developing LRTI. It is feasible to recollect the normal functions of Hb. It facilitates oxygen(O 2 ) and carbon dioxide (CO 2 ) transport. It caries and inactivates nitric oxide (NO) and also play the role of a buffer.[11] Tissue ' oxygen buffer' function is very important one of hemoglobin system. Hemoglobin in the blood is mainly responsible for stabilizing the oxygen pressure in the tissues.[12] Quantitative and/or qualitative reduction in Hb, may adversely affect the normal functions. Probably it may be the reason for low hemoglobin level found to be as a serious risk factor for developing LRTI , 5.75 times more susceptible compared to control.
Acknowledgements
We thank Ms. Sumithra S, Lecturer in bio statistics, for the statistical support provided.
References
1. Thomas P Green, Susanna A. McColley. Disorders of the lungs and lower airways. In Richard E. Behrman, Robert Kleigman, Hal B. Jenson, ed. Nelson Text Book of Pediatrics. 17th ed. Philadelphia; Saunders, 2004: 1401.
2. Wald ER. Recurrent and non resolving pneumonia in children. Sem Resp Infect 1993; 8: 46-58.
3. Suraj Gupte. Common deficiency disorders and their prevention. Recent Advances in Pediatrics . New Delhi; Jaypee Medical Publishers, 1997: 398-400.
4. Theodore C. Sectish, Charles G Prober. Pneumonia. In Richard E. Behrman, Robert Kliegman, Hal B. Jenson, ed. Nelson Text Book of Pediatrics. 17th ed. Philadelphia; Saunders, 2004: 1401.
5. Suraj Gupte. Nutrition, growth and development. Recent Advances in Pediatrics . New Delhi; Jaypee Medical Publishers, 1997: 100-104.
6. Jerald P. Kuhn. Imaging of the thorax. Caffey's Pediatric Diagnostic Imaging . 10th ed. Philadelphia; Mosby, 2004: 768-769.
7. Bhaskaran P, Madhavan Nair K, Balakrishnan N. Serum transferrin receptors in children with respiratory infections. Eur J Nutr 2003; 57: 75-80.
8. De-Silva A, Atukorola S, Weerasinghel. Iron supplementation improves iron status and reduces morbidity in children with or with out URTI. Am J Clin Nutr 2003; 77: 234-241.
9. Forssell G, Hakansson A, Mansson NO. Risk factors for respiratory tract infections in children 2-5 years. Scand Prim Health Care 2001; 19: 122-125.
10. Koch A, Molbak K, Homoe P, Sorensen P, Hjuler T, Olessen ME et al. Risk factors for acute respiratory tract infections in young Greenlandic children. Am J Epidemiol 2003; 158: 374-384.
11. William F Ganong. Gas transport between the lungs and the tissues. Review of Medical Physiology . 22nd ed. New York; Mc Graw-Hill, 2005: 666-669.
12. Guyton & Hall. Effect of hemoglobin to 'Buffer' the tissue PO2. Text Book of Medical Physiology . 11th ed. Philadelphia; Saunders, 2006: 507-508.(Ramakrishnan K, Harish PS)
Abstract
Objective. This prospective study was conducted to evaluate the role of hemoglobin level, as a risk factor for Lower Respiratory Tract Infections in children (LRTI). Methods. 100 children who came to the outpatient department for LRTI were included in the study. Age and sex-matched 100children, not having any respiratory illness, were taken as control. They were subjected to complete blood count (CBC) ,C-reactive protein estimation (CRP), Mantoux test, and X-ray chest. Peripheral smear, serum ferritin and serum iron binding capacity were done for all anemic children. Results. Radiological evidence of pneumonia was present in 63 children(63%).Hyper inflated lungs were seen in 27 (27%). Mantoux was positive in 22 children (22%) of study group and none among control group. CRP > 6mg/L was noted in 45 children (45%) of study group and 14 (14%) of control group. Seventy four of study group (74 %) and 33 of control group (33%) had anemia. Of the anemic children, 60(60%) had iron deficiency,10 (10%) chronic inflammation and 4 (4%) had hemolytic anemia. These values were 30(30%), 2(2%) and1(1%)respectively for control group. Low hemoglobin level due to whatever etiology, was a risk factor (p=0.000). Conclusion. Anemic children were 5.75 times more susceptible to LRTI compared to the control group. Prevention of anemia, due to whatever etiology, will reduce the incidence of LRTI
Keywords: Lower respiratory tract infection; Hemoglobin level
Lower respiratory tract infections (LRTI) include all infections of the lungs and the large airways below the larynx.[1] On an average, children below 5 years of age suffer about 5-6 episodes of LRTI per year.[2]
A child was considered anemic, if the hemoglobin (Hb) level was below 11g/dL.[3] Lower respiratory tract infections associated with anemia occur more commonly in children than in adults. But low hemoglobin level due to whatever etiology per se, as a risk factor for developing LRTI has not been fully evaluated. Hence this prospective study was conducted for assessing low hemoglobin level, as a risk factor for developing LRTI in children.
Material and Methods
This prospective study was conducted in 100 children who attended the out patient unit of Department of Pediatrics, Amrita Institute of Medical Sciences and Research Centre Kochi, during the period of one year from March 2003 to February 2004. Pneumonia was diagnosed by symptoms and clinical signs.[4] Children with the following criteria were exempted from this study: (i) Congenital malformations of chest wall; (ii) Having severe systemic illness; (iii) Protein Energy Malnutrition (PEM > Grade III as per Indian Academy of Pediatrics (IAP) classification .[5]
Weight and height were recorded for all children to assess the nutritional status. The following investigations were done in all cases: Complete Blood Count (CBC), C reactive protein estimation (CRP), Mantoux test and X-ray chest. Peripheral smear, serum ferritin and serum iron binding capacity were done in all anemic children.
Mantoux test was taken as positive with an induration of 10 mm or more .X-ray chest was taken by conventional methods and interpreted as described.[6]
Age and sex-matched 100 children, attending the pediatric outpatient department for check-up with complaints of illness other than LRTI were randomly selected as control.
Statistical Analysis
Numerical variables were reported in terms of mean and standard deviation. Categorical variables were reported in terms of numbers and percentages.
Association of each of the categorical variable with response variable was assessed by Chi-square test and the strength of their association was computed by unadjusted odds ratio. Variables showing statistically significant association in univariate analysis with the outcome variable up to p=0.25 were considered as risk factor. Only those variables were subjected to multivariate analysis. Logistic regression technique was used to find the risk factor for LRTI. In multivariate analysis, variables showing p value less than 0.05 was considered to be statistically significant.
Results
Age group of children varied from 9-months to 16 years. CRP was more than 6 mg/L, in 45 children (45%) in the study group 14(14%) in the control group. Mantoux test was positive for 22 (22%) among study group and none in control group. Radiological evidence of pneumonia was present in 63(63%), and hyperinflation of lung fields in 27 (27%) among study group. Despite clinical signs, X-ray chest were normal in 10 cases (10%). In both groups, age was not found as a significant factor affecting the result. (p=0.38, and 0.47 respectively for study group and control) seventy four children (74%)in the study group and 33 (33%)of control were anemic. Among the anemic children in study group,60(60%) had iron deficiency anemia (IDA),10 (10%) had anemia of chronic infection(ACI) and the rest 4(4%) had hemolytic anemia(HA). Thirty three(33%) children in controls were anemic and 30(30%) out of them had IDA and 2(2%) had ACI and the rest one(1%) was suffering from HA. Descriptive data regarding age, sex , mean and standard deviation of hemoglobin, white blood cell count(WBC) absolute neutrophil ( ANC) and eosinophil count(AEC) are shown in table1.
Fifty eight cases (58%) in the study group had a history of wheeze. Forty (40%) gave a positive family history of asthma.
Discussion
Several risk factors for developing LRTI had been reported in different studies. Baskaran et al in a study of 43 children between 3-5 years had found 83 % with pneumonia had hemoglobin less than 11 g/dL. [7]
In another study of iron deficiency anemia and respiratory infection by De-Silva A et al, an over all prevalence of anemia was found in 52.6%.[8] He concluded that iron treatment significantly reduced the morbidity of even children with URTI.
Attending a day care center was reported as the most important risk factor for respiratory tract infections in children aged 2-5 years.[9] In a community based study of 288 children, risk factors for LRTI noted were being a boy, attending a child care center, exposing to passive smoking and sharing a bed room with children aged 0-5 years. [10]
Few reports are available in literature regarding the role of low hemoglobin level per se, as a risk factor for developing LRTI. We have found that reduced hemoglobin level due to whatever etiology was a significant risk factor for developing LRTI. It is feasible to recollect the normal functions of Hb. It facilitates oxygen(O 2 ) and carbon dioxide (CO 2 ) transport. It caries and inactivates nitric oxide (NO) and also play the role of a buffer.[11] Tissue ' oxygen buffer' function is very important one of hemoglobin system. Hemoglobin in the blood is mainly responsible for stabilizing the oxygen pressure in the tissues.[12] Quantitative and/or qualitative reduction in Hb, may adversely affect the normal functions. Probably it may be the reason for low hemoglobin level found to be as a serious risk factor for developing LRTI , 5.75 times more susceptible compared to control.
Acknowledgements
We thank Ms. Sumithra S, Lecturer in bio statistics, for the statistical support provided.
References
1. Thomas P Green, Susanna A. McColley. Disorders of the lungs and lower airways. In Richard E. Behrman, Robert Kleigman, Hal B. Jenson, ed. Nelson Text Book of Pediatrics. 17th ed. Philadelphia; Saunders, 2004: 1401.
2. Wald ER. Recurrent and non resolving pneumonia in children. Sem Resp Infect 1993; 8: 46-58.
3. Suraj Gupte. Common deficiency disorders and their prevention. Recent Advances in Pediatrics . New Delhi; Jaypee Medical Publishers, 1997: 398-400.
4. Theodore C. Sectish, Charles G Prober. Pneumonia. In Richard E. Behrman, Robert Kliegman, Hal B. Jenson, ed. Nelson Text Book of Pediatrics. 17th ed. Philadelphia; Saunders, 2004: 1401.
5. Suraj Gupte. Nutrition, growth and development. Recent Advances in Pediatrics . New Delhi; Jaypee Medical Publishers, 1997: 100-104.
6. Jerald P. Kuhn. Imaging of the thorax. Caffey's Pediatric Diagnostic Imaging . 10th ed. Philadelphia; Mosby, 2004: 768-769.
7. Bhaskaran P, Madhavan Nair K, Balakrishnan N. Serum transferrin receptors in children with respiratory infections. Eur J Nutr 2003; 57: 75-80.
8. De-Silva A, Atukorola S, Weerasinghel. Iron supplementation improves iron status and reduces morbidity in children with or with out URTI. Am J Clin Nutr 2003; 77: 234-241.
9. Forssell G, Hakansson A, Mansson NO. Risk factors for respiratory tract infections in children 2-5 years. Scand Prim Health Care 2001; 19: 122-125.
10. Koch A, Molbak K, Homoe P, Sorensen P, Hjuler T, Olessen ME et al. Risk factors for acute respiratory tract infections in young Greenlandic children. Am J Epidemiol 2003; 158: 374-384.
11. William F Ganong. Gas transport between the lungs and the tissues. Review of Medical Physiology . 22nd ed. New York; Mc Graw-Hill, 2005: 666-669.
12. Guyton & Hall. Effect of hemoglobin to 'Buffer' the tissue PO2. Text Book of Medical Physiology . 11th ed. Philadelphia; Saunders, 2006: 507-508.(Ramakrishnan K, Harish PS)