Spirometry reference values for American Indian adults: results from the Strong Heart Study

Area of Science:

• Pulmonary Medicine
• Public Health
• Epidemiology

Background:

• Spirometry is crucial for diagnosing lung diseases.
• Existing reference values may not accurately represent diverse populations.
• American Indian adults have unique health profiles.

Purpose of the Study:

• To establish normative spirometry values for American Indian adults.
• To compare these values with existing reference standards for white adults.
• To assess the applicability of current reference equations in this demographic.

Main Methods:

• The Strong Heart Study collected spirometry data from American Indian adults aged 45-74.
• Internal reference equations were derived from a healthy subgroup.
• Data were analyzed using American Thoracic Society guidelines and quality assurance protocols.

Main Results:

• Airway obstruction was identified in 10% of the cohort using internal equations.
• Comparison with NHANES III (white adult) equations showed low misclassification rates (1.3% false-positive, 1.2% false-negative).
• Prevalence of low forced vital capacity (FVC) was 17.6%.

Conclusions:

• NHANES III spirometry reference equations for white adults can be utilized for American Indian men and women aged 45-74.
• These findings support the clinical use of existing equations while acknowledging potential population-specific variations.