The use of estimating height in lung function assessment (1)
Research type
Research Study
Full title
The use of estimating height in lung function assessment: exploring the potential impact of disease related decrease in height on spirometry results – a pilot study.
IRAS ID
183003
Contact name
Sophie Pad
Contact email
Sponsor organisation
Newcastle University
Duration of Study in the UK
0 years, 5 months, 4 days
Research summary
In lung function testing, results are compared against predicted values to assess normality. Predicted values are calculated for each individual depending on age, gender, and height, with spirometry results expressed as percentage of predicted to guide diagnosis and treatment. However, patients seen within the lung function laboratory commonly comment on height loss and are known to be at higher risk of declines in stature. Therefore many patients could have excessive height loss, causing inappropriate underestimation of predicted values. This could correspondingly change percentage of predicted results, leading to misinterpretation.
A method of estimating height, free of excessive height loss, is needed. Arm span closely approximates to height and can be used to estimate height, but current methods do not fully take account of the sources of variance in the arm span to height relationship. However, equations were developed recently based on nearly 14,000 healthy subjects to enable height estimation from arm span taking into account these sources of variance.This provides a tool to explore the potential impact of height loss. Whilst a reduction in measured height relative to estimated height in respiratory patients may be expected, it is unknown whether such differences would in turn have any clinically significant impact on spirometry results.
This pilot study will provide data to enable the design of a future study using this method in patients undergoing spirometry. The study will provide data to calculate an appropriate sample size and assess the feasibility of the approach. Furthermore, it will provide an indication of the impact of using estimated height on spirometry results at this stage. Participants undergoing routine lung function testing in the York hospital pulmonary function laboratory over age 50 years will be recruited to assess the use and effect of estimating height on spirometry results in this population.
REC name
London - Bloomsbury Research Ethics Committee
REC reference
15/LO/1984
Date of REC Opinion
12 Nov 2015
REC opinion
Favourable Opinion