Prognostic implications of differences in forced vital capacity in black and white US adults: Findings from NHANES III with long-term mortality follow-up.
EClinicalMedicine
; 39: 101073, 2021 Sep.
Article
in En
| MEDLINE
| ID: mdl-34458707
ABSTRACT
BACKGROUND:
Because Forced Vital Capacity (FVC) is reduced in Black relative to White Americans of the same age, sex, and height, standard lung function prediction equations assign a lower "normal" range for Black patients. The prognostic implications of this race correction are uncertain.METHODS:
We analyzed 5,294 White and 3,743 Black participants age 20-80 in NHANES III, a nationally-representative US survey conducted 1988-94, which we linked to the National Death Index to assess mortality through December 31, 2015. We calculated the FVC-percent predicted among Black and White participants, first applying NHANES III White prediction equations to all persons, and then using standard race-specific prediction equations. We used Cox proportional hazard models to calculate the association between race and all-cause mortality without and with adjustment for FVC (using each FVC metric), smoking, socioeconomic factors, and comorbidities.FINDINGS:
Black participants' age- and sex-adjusted mortality was greater than White participants (HR 1.46; 95%CI1.29, 1.65). With adjustment for FVC in liters (mean 3.7 L for Black participants, 4.3 L for White participants) or FVC percent-predicted using White equations for everyone, Black race was no longer independently predictive of higher mortality (HRâ¼1.0). When FVC-percent predicted was "corrected" for race, Black individuals again showed increased mortality hazard. Deaths attributed to chronic respiratory disease were infrequent for both Black and White individuals.INTERPRETATION:
Lower FVC in Black people is associated with elevated risk of all-cause mortality, challenging the standard assumption about race-based normal limits. Black-White disparities in FVC may reflect deleterious social/environmental exposures, not innate differences.FUNDING:
No funding.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Type of study:
Diagnostic_studies
/
Prognostic_studies
Language:
En
Journal:
EClinicalMedicine
Year:
2021
Type:
Article
Affiliation country:
United States