Jm. Parker et al., IMPACT OF USING STATED INSTEAD OF MEASURED HEIGHT UPON SCREENING SPIROMETRY, American journal of respiratory and critical care medicine, 150(6), 1994, pp. 1705-1708
Citations number
14
Categorie Soggetti
Emergency Medicine & Critical Care","Respiratory System
This study examined the impact of using stated height instead of measu
red height on predicted normal values and clinical interpretation of s
creening spirometry in an outpatient referral population. In a prospec
tive fashion, we evaluated 210 patients, 20 to 89 yr of age, referred
for spirometry to our pulmonary function laboratory by obtaining both
stated height (HTs) and measured height (HTm). The mean difference bet
ween stated and measured height progressively increased with age, from
0.80 cm (20 to 29 yr; p = 0.01) to 5.70 cm (80 to 89 yr; p < 0.001).
For men and women, use of HTs instead of HTm produced a mean differenc
e for all ages in computing predicted FEV(1), and FVC values of 3.9 an
d 4.3%, respectively. This effect was more prominent in the older age
groups (80 to 89 yr, n = 30); mean differences were 11.0% (211 ml) and
11.7% (303 ml), respectively. Use of HTs instead of HTm altered the d
etection of restriction by reduced FVC in 17 patients and the detectio
n of obstruction by reduced FEV(1)/FVC ratio in four patients. Use of
HTs altered the clinical assessment of severity by FEV(1) in 15 of 108
(13.9%) obstructed patients and altered the assessment of severity by
FVC in 11 of 32 (34.4%) restricted patients, with older patients more
frequently affected than younger patients. We conclude that the use o
f stated height instead of measured height in the performance of scree
ning spirometry can have significant impact on the calculation of pred
icted normal values. These discrepancies can potentially influence the
clinical interpretation of screening spirometry, affecting the detect
ion of abnormality and the assessment of severity of disease, particul
arly among older patients.