A follow-up study of children hospitalised with community-acquired pneumonia

Pulmonary Function in Pediatric Stem Cell Transplantation

BACKGROUND

Pediatric hematopoietic stem cell transplantation often results in pulmonary complications, yet limited data exist on pulmonary function in Thailand. This study aims to assess pulmonary function, investigating associated complications and identifying clinical factors linked to pre- and post-transplant pulmonary function defects.

METHODS

In this retrospective cohort study, we focused on children aged 6-18 years who underwent hematopoietic stem cell transplantation between 1999 and 2020, ensuring accessible pulmonary function tests results.

RESULTS

Among 48 patients, abnormal pulmonary function pre- and post-transplant (2-8 years) included a diffusion defect in 16.7% and 18.8%, a restrictive defect in 20.8% and 8.3%, and an obstructive defect in 4.2% and 10.4%, respectively. Pulmonary complications occurred in 16 patients (33.3%), including 15 infections and 1 case of bronchiolitis obliterans. While pretransplant pulmonary function defects were not significantly associated with specific characteristics, post-transplant pulmonary complications correlated with post-transplant pulmonary function defects (aOR = 4.11, 95% CI = 1.23-13.64, P = .02). Among the 6 patients with pre- and post-transplant follow-up, those with pulmonary complications showed a discernible decline in pulmonary function over time, while those without pulmonary complications remained stable or improved. However, the differences between these groups did not reach statistical significance (P = .13-.76).

CONCLUSIONS

Prevalent pulmonary function defects and complications in pediatric hematopoietic stem cell transplantation highlight the importance of close pulmonary function monitoring. Post-transplant pulmonary complications are associated with defects, suggesting a potential trend of a subsequent decline in lung function, warranting further prospective validation.

Factors associated with severe pneumonia among children <5 years, Kasese District, Uganda: a case-control study, January-April 2023

BACKGROUND

Pneumonia is one of the leading causes of infant mortality globally, particularly in sub-Saharan Africa. In Uganda, pneumonia was the fourth leading cause of death in children <5 years in 2018. Analysis of 2013-2022 data for children <5 years from the District Health Information System indicated a high incidence of severe pneumonia in Kasese District, Uganda. We investigated to identify factors associated with severe pneumonia among children <5 years in Kasese District to inform prevention and control strategies.

METHODS

We conducted a 1:1 hospital-based case-control study among children aged 2-59 months presenting with pneumonia at five high-volume facilities in Kasese District from January to April 2023. A case was defined as pneumonia with ≥1 of the following danger signs: low oxygen saturation, central cyanosis, severe respiratory distress, feeding difficulties, altered consciousness, and convulsions. Controls were outpatient children aged 2-59 months with a diagnosis of non-severe pneumonia. We reviewed medical records at facilities and used an interviewer-administered questionnaire with caregivers to obtain information on socio-demographic and clinical characteristics. Logistic regression was used to identify factors associated with severe pneumonia.

RESULTS

We enrolled 199 cases and 174 controls. The odds of severe pneumonia were higher among children with diarrhoea only (adjusted odds ratio [aOR] = 2.9, 95%CI: 1.7-4.9), or malaria and diarrhoea (aOR = 3.4, 95%CI: 2.0-5.9), than those without a co-existing illness at the time of pneumonia diagnosis. Not being exclusively breastfed for ≥ 6 months (aOR = 2.0, 95%CI: 1.1-3.3) and exposure to indoor air pollution from cooking combustion sources (aOR = 2.9, 95%CI: 1.8-4.7) increased odds of severe pneumonia.

CONCLUSION

The findings highlight the significance of comorbidities, lack of exclusive breastfeeding, and exposure to indoor air pollution in the development of severe pneumonia. Promoting exclusive breastfeeding for ≥ 6 months and advocating for the use of clean energy sources, could mitigate morbidity attributable to severe pneumonia in the region.

Time to re-set our thinking about airways disease: lessons from history, the resurgence of chronic bronchitis / PBB and modern concepts in microbiology

In contrast to significant declines in deaths due to lung cancer and cardiac disease in Westernised countries, the mortality due to 'chronic obstructive pulmonary disease' (COPD) has minimally changed in recent decades while 'the incidence of bronchiectasis' is on the rise. The current focus on producing guidelines for these two airway 'diseases' has hindered progress in both treatment and prevention. The elephant in the room is that neither COPD nor bronchiectasis is a disease but rather a consequence of progressive untreated airway inflammation. To make this case, it is important to review the evolution of our understanding of airway disease and how a pathological appearance (bronchiectasis) and an arbitrary physiological marker of impaired airways (COPD) came to be labelled as 'diseases'. Valuable insights into the natural history of airway disease can be obtained from the pre-antibiotic era. The dramatic impacts of antibiotics on the prevalence of significant airway disease, especially in childhood and early adult life, have largely been forgotten and will be revisited as will the misinterpretation of trials undertaken in those with chronic (bacterial) bronchitis. In the past decades, paediatricians have observed a progressive increase in what is termed 'persistent bacterial bronchitis' (PBB). This condition shares all the same characteristics as 'chronic bronchitis', which is prevalent in young children during the pre-antibiotic era. Additionally, the radiological appearance of bronchiectasis is once again becoming more common in children and, more recently, in adults. Adult physicians remain sceptical about the existence of PBB; however, in one study aimed at assessing the efficacy of antibiotics in adults with persistent symptoms, researchers discovered that the majority of patients exhibiting symptoms of PBB were already on long-term macrolides. In recent decades, there has been a growing recognition of the importance of the respiratory microbiome and an understanding of the ability of bacteria to persist in potentially hostile environments through strategies such as biofilms, intracellular communities, and persister bacteria. This is a challenging field that will likely require new approaches to diagnosis and treatment; however, it needs to be embraced if real progress is to be made.

Community-acquired pneumonia in infants: Not simply an acute event with complete recovery

BACKGROUND

Pneumonia in infancy has been linked to long-term consequences for the rapidly developing lung. We examined the impact of hospitalized community-acquired pneumonia (CAP) on subsequent respiratory health.

METHODS

We conducted a retrospective matched-cohort study using the Optum® de-identified Electronic Health Record Dataset (2009-2018). Study population comprised healthy infants hospitalized for CAP ("CAP patients"), and matched comparators without pneumonia ("comparison patients"), before age 2 years. Study outcomes included any chronic respiratory disorder, reactive airway disease (asthma, hyperactive airway disease, recurrent wheezing), and CAP hospitalization occurring between age 2-5 years, and were evaluated overall as well as by age and etiology at first CAP hospitalization.

RESULTS

Study population totaled 1,343 CAP patients and 6,715 comparison patients. Rates per 100 patient-years and relative rates (RR) of study outcomes from age 2-5 years for CAP patients versus comparison patients were: any chronic respiratory disorder, 11.6 vs. 4.9 (RR = 2.4 [95% CI: 2.1-2.6]); reactive airway disease, 6.1 vs 1.9 (RR = 3.2 [2.6-3.8]); and CAP hospitalization, 1.0 vs 0.2 (RR = 6.3 [3.6-10.9]). Rates of study outcomes were highest among CAP patients who had their initial hospitalization in the second year of life.

CONCLUSIONS

Infant CAP foreshadows an increased risk of subsequent chronic respiratory disorders, which may be elevated when CAP occurs closer to pre-school age (i.e., age 2-5 years). These findings are most consistent with the hypothesis that inflammation persists beyond the acute stage of pneumonia and plays a role in the development of chronic respiratory sequelae.

Prospective community programme versus parent-driven care to prevent respiratory morbidity in children following hospitalisation with severe bronchiolitis or pneumonia

BACKGROUND

Hospitalisation with severe lower respiratory tract infection (LRTI) in early childhood is associated with ongoing respiratory symptoms and possible later development of bronchiectasis. We aimed to reduce this intermediate respiratory morbidity with a community intervention programme at time of discharge.

METHODS

This randomised, controlled, single-blind trial enrolled children aged <2 years hospitalised for severe LRTI to 'intervention' or 'control'. Intervention was three monthly community clinics treating wet cough with prolonged antibiotics referring non-responders. All other health issues were addressed, and health resilience behaviours were encouraged, with referrals for housing or smoking concerns. Controls followed the usual pathway of parent-initiated healthcare access. After 24 months, all children were assessed by a paediatrician blinded to randomisation for primary outcomes of wet cough, abnormal examination (crackles or clubbing) or chest X-ray Brasfield score ≤22.

FINDINGS

400 children (203 intervention, 197 control) were enrolled in 2011-2012; mean age 6.9 months, 230 boys, 87% Maori/Pasifika ethnicity and 83% from the most deprived quintile. Final assessment of 321/400 (80.3%) showed no differences in presence of wet cough (33.9% intervention, 36.5% controls, relative risk (RR) 0.93, 95% CI 0.69 to 1.25), abnormal examination (21.7% intervention, 23.9% controls, RR 0.92, 95% CI 0.61 to 1.38) or Brasfield score ≤22 (32.4% intervention, 37.9% control, RR 0.85, 95% CI 0.63 to 1.17). Twelve (all intervention) were diagnosed with bronchiectasis within this timeframe.

INTERPRETATION

We have identified children at high risk of ongoing respiratory disease following hospital admission with severe LRTI in whom this intervention programme did not change outcomes over 2 years.

TRIAL REGISTRATION NUMBER

ACTRN12610001095055.

Respiratory sequelae and quality of life in children one-year after being admitted with a lower respiratory tract infection: A prospective cohort study from a developing country

INTRODUCTION

Respiratory tract infections in children can result in respiratory sequelae. We aimed to determine the prevalence of, and factors associated with persistent respiratory sequelae 1 year after admission for a lower respiratory tract infection (LRTI).

METHODOLOGY

This prospective cohort study involved children 1 month to 5-years-old admitted with an LRTI. Children with asthma were excluded. Patients were reviewed at 1-, 6-, and 12-months post-hospital discharge. The parent cough-specific quality of life, the depression, anxiety, and stress scale questionnaire and cough diary for 1 month, were administered. Outcomes reviewed were number of unscheduled healthcare visits, respiratory symptoms and final respiratory diagnosis at 6 and/or 12 month-review by pediatric pulmonologists.

RESULTS

Three hundred patients with a mean ± SD age of 14 ± 15 months old were recruited. After 1 month, 239 (79.7%) returned: 28.5% (n = 68/239) had sought medical advice and 18% (n = 43/239) had cough at clinic review. Children who received antibiotics in hospital had significantly lower total cough scores (P = .005) as per the cough diary. After 1 year, 26% (n = 78/300) had a respiratory problem, predominantly preschool wheezing phenotype (n = 64/78, 82.1%). Three children had bronchiectasis or bronchiolitis obliterans. The parent cough-specific quality of life (PCQOL) was significantly lower in children with respiratory sequelae (P < .01). In logistic regression, the use of antibiotics in hospitals (adjusted odds ratio, 0.46; P = .005) was associated with reduced risk of respiratory sequelae.

CONCLUSION

In children admitted for LRTI, a quarter had respiratory sequelae, of which preschool wheeze was the commonest. The use of antibiotics was associated with a lower risk of respiratory sequelae.

Clinical, functional, and radiological outcome in children with pleural empyema

INTRODUCTION

Few studies have prospectively evaluated recovery process and long-term consequences of pleural space infections.

OBJECTIVE

To evaluate clinical, pulmonary, and diaphragmatic function and radiological outcome in patients hospitalized with pleural empyema.

MATERIAL AND METHODS

Previously healthy patients from 6 to 16 years were enrolled. Demographic, clinical, and treatment data were registered. At hospital discharge, and every 30 days or until normalization, patients underwent a clinical evaluation, diaphragmatic ultrasound, and lung function testing. Chest radiographs were performed at subsequent visits only if abnormalities persisted.

RESULTS

Thirty patients were included. Nineteen (63%) were male, with an age of (mean ± SD) 9.7 ± 3.2 years, and body mass index (mean ± SD) 18.6 ± 3. Twelve patients (40%) were treated with chest tube drainage only, 12 (40%) exclusively with surgery, and 6 (20%) completed treatment with surgery due to an ineffective chest tube drainage. At hospital discharge, 26 (87%) of patients had abnormal breath sounds at the site of infection, 28 (93%) had a spirometric restrictive pattern, 19 (63%) diaphragmatic motion impairment, and 29 (97%) presented radiological involvement of pleural space, mainly pleural thickening. All patients had recovered diaphragmatic motion and were asymptomatic at 90- and 120-day follow-up control, respectively. Then, with a great individual variability, radiological findings, and lung function returned to normal at 60 days (range 30-180) and 90 days (range 30-180) after hospital discharge, respectively.

CONCLUSION

Patients with pleural empyema had a complete and progressive recovery, with initial clinical and diaphragmatic motion normalization followed by radiological and lung function recovery.

Long-term effects of pneumonia in young children

Each year an estimated 120 million episodes of pneumonia occur in children younger than 5 years of age, resulting in one million deaths globally. Within this age group the lungs are still developing by increasing alveoli numbers and airway dimensions. Pneumonia during this critical developmental period may therefore adversely affect the lung's structure and function, with increased risk of subsequent chronic lung disease. However, there are few longitudinal studies of pneumonia in otherwise healthy children that extend into adulthood to help address this important question. Birth cohort, longitudinal, case-control and retrospective studies have reported restrictive and obstructive lung function deficits, asthma, bronchiectasis, and chronic obstructive pulmonary disease. In particular, severe hospitalised pneumonia had the greatest risk for long-term sequelae. Most studies, however, were limited by incomplete follow-up, some reliance upon parental recall, risk of diagnostic misclassification, and potential confounders such as nutrition, social deprivation, and pre-existing small airways or lungs. More long-term studies measuring lung function shortly after birth are needed to help disentangle the complex relationships between pneumonia and later chronic lung disease, while also addressing host responses, types of infection, and potential confounding variables. Meanwhile, parents of young children with pneumonia need to be advised about the importance of symptom resolution, post-pneumonia. In addition, paying attention to factors associated with optimising lung growth such as good nutrition, minimising exposure to air pollution, avoiding cigarette smoke, and decreasing the risk of preventable infections through good hygiene and having their children fully vaccinated should be emphasised. Finally, in the developing world and for disadvantaged communities in developed countries, public health policies leading to good quality housing and heating, hygiene, education, and improving socio-economic status are also essential.

Long-term outcome of parapneumonic effusions in children: Lung function and exercise tolerance

OBJECTIVES

a: To evaluate the long-term outcome of parapneumonic effusions (PPE) in children regarding lung function and exercise tolerance, (b) to investigate the role of bronchial asthma in the outcome of PPE.

METHODS

The design of the study included 51 children with PPE, at least 2 years after the initial infection. They were divided in two groups. Group A (38 children) consisted of children with PPE but without asthma prior initial infection. Group B (13 children) included children with PPE and asthma prior infection. Thirty-six children were taken as healthy controls (group C). All children performed spirometry and a maximal incremental cardiopulmonary exercise test on cycle ergometer.

RESULTS

Children of both groups (A and B) showed statistically significant lower values in FVC%, FEV1%, and FEV1 /FVC compared to controls (group C). Children of group B had also significant lower FEF(25-75%) values compared to controls. Children of group B had significant lower FEV1 /FVC values compared to group A. All children of the three groups showed no differences in maximal exercise capacity (VO2max). Children of group A had higher respiratory equivalent to oxygen (VE/VO2) during exercise compared to healthy subjects.

CONCLUSIONS

There are small effects on lung function and exercise capacity in the long-term, among children with PPE, but of no clinical importance. Pre-existing bronchial asthma doesn't influence the outcome significantly.

Long-term recovery after parapneumonic empyema in children

BACKGROUND

The incidence of parapneumonic empyema in children has increased worldwide, but the long-term anatomical and functional consequences in the lungs after empyema are not known.

METHODS

We investigated the long-term outcome of childhood empyema in 26 patients by physical examination, chest radiograph and magnetic resonance image (MRI) of the lungs, and pulmonary function tests.

RESULTS

At follow-up 3-19 years (mean 8 years) after empyema, all patients had normal findings in the physical examination. Spirometry was normal in 80% of patients, and evidence of obstructive airway disease was detected in 16%. Thirty-six percent of patients had abnormal findings in the chest radiograph and 92% in the MRI of the lungs. In six patients, the MRI revealed significant pleural scarring (extension longer than 1 cm). Thirteen patients (50%) reported persistent respiratory symptoms, such as impaired tolerance of physical activity or prolonged cough after a common cold. During the follow-up four patients suffered a second pneumonia.

CONCLUSIONS

The long-term recovery of children with parapneumonic empyema is good, since most patients subsequently have normal lung function, chest radiograph, and clinical recovery. Half of the patients reported subjective respiratory symptoms and most patients had minor lung abnormalities, mostly pleural scars, detected in the MRI many years after empyema. However, as long-term impairment of lung function was rarely found, the clinical significance of the anatomical residues seen in the lung MRI seems to be minor.

Improving the Diagnosis, Management, and Outcomes of Children with Pneumonia: Where are the Gaps?

Pneumonia is the greatest contributor to childhood mortality and morbidity in resource-poor regions, while in high-income countries it is one of the most common reasons for clinic attendance and hospitalization in this age group. Furthermore, pneumonia in children increases the risk of developing chronic pulmonary disorders in later adult life. While substantial advances in managing childhood pneumonia have been made, many issues remain, some of which are highlighted in this perspective. Multiple studies are required as many factors that influence outcomes, such as etiology, patient characteristics, and prevention strategies can vary between and within countries and regions. Also, outside of vaccine studies, most randomized controlled trials (RCTs) on pneumonia have been based in resource-poor countries where the primary aim is usually prevention of mortality. Few RCTs have focused on medium to long-term outcomes or prevention. We propose different tiers of primary outcomes, where in resource-rich countries medium to long-term sequelae should also be included and not just the length of hospitalization and readmission rates.

Respiratory health outcomes 1 year after admission with severe lower respiratory tract infection

Severe lower respiratory infection (LRI) is believed to be one precursor of protracted bacterial bronchitis, chronic moist cough (CMC), and chronic suppurative lung disease. The aim of this study was to determine and to describe the presence of respiratory morbidity in young children 1 year after being hospitalized with a severe LRI. Children aged less than 2 years admitted from August 1, 2007 to December 23, 2007 already enrolled in a prospective epidemiology study (n = 394) were included in this second study only if they had a diagnosis of severe bronchiolitis or of pneumonia with no co-morbidities (n = 237). Funding allowed 164 to be identified chronologically, 131 were able to be contacted, and 94 agreed to be assessed by a paediatrician 1 year post index admission. Demographic information, medical history and a respiratory questionnaire was recorded, examination, pulse oximetry, and chest X-ray (CXR) were performed. The predetermined primary endpoints were; (i) history of CMC for at least 3 months, (ii) the presence of moist cough and/or crackles on examination in clinic, and (iii) an abnormal CXR when seen at a time of stability. Each CXR was read by two pediatric radiologists blind to the individuals' current health. Results showed 30% had a history of CMC, 32% had a moist cough and/or crackles on examination in clinic, and in 62% of those with a CXR it was abnormal. Of the 81 children with a readable follow-up X-ray, 11% had all three abnormal outcomes, and 74% had one or more abnormal outcomes. Three children had developed bronchiectasis on HRCT. The majority of children with a hospital admission at <2 years of age for severe bronchiolitis or pneumonia continued to have respiratory morbidity 1 year later when seen at a time of stability, with a small number already having sustained significant lung disease.

Long term sequelae from childhood pneumonia; systematic review and meta-analysis

Background

The risks of long term sequelae from childhood pneumonia have not been systematically assessed. The aims of this study were to: (i) estimate the risks of respiratory sequelae after pneumonia in children under five years; (ii) estimate the distribution of the different types of respiratory sequelae; and (iii) compare sequelae risk by hospitalisation status and pathogen.

Methods

We systematically reviewed published papers from 1970 to 2011. Standard global burden of disease categories (restrictive lung disease, obstructive lung disease, bronchiectasis) were labelled as major sequelae. ‘Minor’ sequelae (chronic bronchitis, asthma, other abnormal pulmonary function, other respiratory disease), and multiple impairments were also included. Thirteen papers were selected for inclusion. Synthesis was by random effects meta-analysis and meta-regression.

Results

Risk of at least one major sequelae was 5.5% (95% confidence interval [95% CI] 2.8–8.3%) in non hospitalised children and 13.6% [6.2–21.1%]) in hospitalised children. Adenovirus pneumonia was associated with the highest sequelae risk (54.8% [39.2–70.5%]) but children hospitalised with no pathogen isolated also had high risk (17.6% [10.9–24.3%]). The most common type of major sequela was restrictive lung disease (5.4% [2.5–10.2%]) . Potential confounders such as loss to follow up and median age at infection were not associated with sequelae risk in the final models.

Conclusions

All children with pneumonia diagnosed by a health professional should be considered at risk of long term sequelae. Evaluation of childhood pneumonia interventions should include potential impact on long term respiratory sequelae.

Does a parent-reported history of pneumonia increase the likelihood of respiratory symptoms needing therapy in asthmatic children and adolescents?

BACKGROUND

Asthmatic children and adolescents attending outpatient clinics often have a history of pneumonia. Whether respiratory symptoms, lung function, and airway inflammation differ in asthmatic patients with and without a history of pneumonia remains controversial.

AIMS

To compare clinical, lung functional, and inflammatory variables in asthmatic outpatients with and without a history of pneumonia. Methods. In 190 asthmatic outpatients, aged 6-18 years, we assessed respiratory symptoms, lung function (flows, volumes, and pulmonary diffusion capacity, DLCO/VA), and atopic-airway inflammation as measured by the fractional concentration of exhaled nitric oxide (FE(NO)). A previous medical and radiological diagnosis of pneumonia was defined as "recurrent pneumonia" if subjects had at least three pneumonia episodes or two episodes within a year.

RESULTS

Of the 190 outpatients studied, 38 (20%) had a history of pneumonia. These patients had more frequent upper-respiratory symptoms, nighttime awakenings in the past 4 weeks, daily use of inhaled corticosteroids, and lower FE(NO) than the 152 asthmatic children without previous pneumonia (FE(NO): 20.6 ppb, 95% CI: 15.2-28.0 vs. 31.1 ppb, 95% CI: 27.0-35.8; p < .05). Of the 38 patients with previous pneumonia, 14 had recurrent pneumonia. Despite comparable lung volumes and flows, they also had lower DLCO/VA than asthmatic children with no recurrent pneumonia and asthmatic children without previous pneumonia (DLCO/VA%: 91.2 ± 11.3 vs. 108.5 ± 14.7 vs. 97.9 ± 18.6, p < .05).

CONCLUSION

Respiratory assessment in asthmatic children and adolescents with a history of pneumonia, especially recurrent pneumonia, often discloses symptoms needing corticosteroid therapy, and despite normal lung volumes and flows, mild reductions in the variables reflecting gas diffusion and atopic-airway inflammation (DLCO/VA and FE(NO)). Whether these respiratory abnormalities persist in adulthood remains an open question.

Pneumonia in the developed world

In this paper, we review the literature on the management of pneumonia in the developed world setting. Pneumonia is usually diagnosed on the basis of a cough, respiratory distress, a fever, and chest X-ray changes. Pneumonia affects all paediatric age groups, though the highest incidence is in the under 5s. There is a significant burden of primary and secondary care illness, although mortality is low. Inpatient admission rates for pneumonia may have increased in recent years in some regions. Pneumonia is unlikely if a child presents with solely wheeze. In routine clinical practice, a microbiological diagnosis is often not made, because current tests are insensitive. Aetiology varies with geographical location, but approximately half of cases are viral. The mainstay of management of moderate pneumonia (the commonest group presenting to secondary care) is careful assessment, and oral antibiotics, followed by early discharge when the patient shows signs of improvement. We summarise the available clinical trial data from the developed world; most of these trials are not adequately powered. Patients with moderately severe pneumonia do not require invasive investigation, but clinical judgement should be used to identify and investigate more complex cases. We discuss several pathogens that have gained importance as causal agents, including non-vaccinated strains of S. pneumoniae, Panton Valentine leucocidin S. aureus, H1N1 Influenza A and Human Bocavirus. The importance of antimicrobial resistance is considered, and we review recent data on long term effects of pneumonia in childhood. By reviewing the available literature, we demonstrate that there are clear evidence gaps, and we suggest future areas for clinical research.

Childhood respiratory illness and lung function at ages 14 and 50 years: childhood respiratory illness and lung function

BACKGROUND

Although childhood respiratory tract infections and low birth weight have both been associated with reduced adult lung function, little is known about the timing of these associations during life. We used data from the Newcastle Thousand Families Study to examine how these and other factors influenced FEV(1) at age 14 years and between 14 and 49 to 51 years.

METHODS

Detailed information was collected prospectively during childhood. At age 14 years, 252 members of the cohort were recruited into a case-control study of respiratory health, which included measurement of FEV(1). One hundred twenty-two of these were measured again at age 49 to 51 years. Linear regression models were used to examine cross-sectional and longitudinal influences on FEV(1).

RESULTS

Lower height (P < .001), lower BMI (P < .001), being breast fed for less than 4 weeks (P = .028), childhood history of severe respiratory illness (P = .014), childhood history of asthma (P = .004), childhood history of TB (P = .023), and birth into a lower social class (P = .049) were all significant independent predictors of lower FEV(1) at 14 years of age. Correspondingly, being a women (P < .001), and having a higher FEV(1) at age 14 years (P < .001), a lower standardized birth weight (P = .025), a greater lifetime number of cigarettes smoked (P = .007), and a childhood history of severe respiratory illness (P = .047) were all independently associated with a greater decline (or a smaller increase) in FEV(1) between age 14 and 49 to 51 years.

CONCLUSIONS

This study suggests that the change in FEV(1) between youth and middle age depends on several factors acting throughout life, including FEV(1) in adolescence, sex, cigarette smoking, birth weight, and childhood respiratory health.