Spirometry reference values for healthy elderly blacks. The Cardiovascular Health Study Research Group

Area of Science:

• Pulmonary Medicine
• Geriatric Health
• Clinical Physiology

Background:

• Spirometry is crucial for assessing pulmonary function in the elderly.
• Existing reference values for spirometry are often based on middle-aged white populations.
• The accuracy of applying these values to diverse elderly populations, particularly Black individuals, is questionable.

Purpose of the Study:

• To establish accurate spirometry reference equations for elderly Black individuals.
• To compare pulmonary function measurements between healthy elderly Black and white participants.
• To evaluate the validity of current race correction factors used in spirometry.

Main Methods:

• Spirometry was performed on 497 Black and 2,980 white participants in the Cardiovascular Health Study.
• A healthy subgroup (age ≥65) was defined by excluding smokers, those with respiratory conditions, heart failure, and poor spirometry quality.
• Reference equations for FEV1, FVC, and FEV1/FVC ratio were derived from the healthy Black subgroup.

Main Results:

• Healthy elderly Black participants exhibited a forced vital capacity (FVC) approximately 6% lower than healthy elderly white participants.
• This difference persisted even after adjusting for standing height, sitting height, and age.
• Current spirometry reference values, using a 12% race correction for Black patients, likely overestimate predicted lung function.

Conclusions:

• Established reference equations for elderly Black individuals indicate lower FVC compared to elderly white individuals.
• The standard 12% race correction factor may lead to overestimation of predicted spirometry values in Black populations.
• Revised spirometry reference values are needed for accurate pulmonary function assessment in elderly Black men and women.