Investigation of Lungfunction Normal Values in Children and Adolescent in Germany

Synopsis: LUNOKID-Study

Investigation of Lung function Normal Values in Children and Adolescent in Germany

For the diagnostic work-up of childhood airway diseases lungfunction measurements play an important role. As childhood represents a period of continuous development and growth, not only is body size and weight increasing and body composition changing with age, but also is the lung developing both in size and airway differentiation. Results from lung function measurements in children and adolescents have thus to be related to lung function data which have been determined in a normal healthy age-matched childhood population. The quality of the reference values is therefore crucial for the interpretation of lung function results.

The reference values for children that are used today have been created between around the 1970th or 1980th, although the development and body size of children in the last decades has considerably changed and accelerated.

The aim of the LUNOKID study is to create new reference values for lung function measures in healthy children aged 4 to 18 years. Measurements will be performed in schools and "kindergartens" in 3 regions of Germany (Wesel, Düsseldorf, Hannover).

A modified ISAAC questionnaire will be distributed to the parents to get information on the family´s and child´s health history with regard to atopy, airway diseases or other diseases that could influence the lung function results. A clinical examination on the day of lung function performance should exclude acute infections or other diseases. Parents will have to give informed consent to the study.

Study personal, especially trained in the lung function unit of the University Hannover, is going to do all examination and lung function measures during the normal school hours at the sites of the schools and kindergartens.

The following measurements will be performed according to the respective SOPs:

• Body weight and hight
• Exhaled NO, using the NIOX -MINO in children from the age of 5 years onwards, in 4 years old children using the off-line method (both Aerocrine)
• Spirometry including Flow volume curves (Parameter FEV1, FEV0.5, FEV 0.75, PEF, FVC, MEF 25, MEF 50, MEF 75) using a Spirometer by the company ndd Medizintechnik AG, Zürich
• Ultrasonic pneumography (UPG) (tidal breathing), ndd Medizintechnik AG, Zürich

It is planned to have 50 valid measurements per gender and age group. Considering that about 50 % of the children (and 50-75% of the 4 years´old) have to be excluded for the "normal reference analysis" either for health reasons or because the lung function measurement cannot be correctly performed. The investigators therefore calculate to included in the study around 3300 children.

All data will be gathered and managed in a central database in the IUF in Düsseldorf. The statical analysis will include regression analyses to calculate the reference values.

It is planned to have the new reference values included in the guidelines for diagnostic and management of asthma in childhood, and in the software of lung function equipment. By now, the study is approved by the Ethical Committee responsible for the PI in Wesel.