Lower FEV1 spirometry grades (D/F vs A) were associated with an increased risk of mortality in multivariable analysis (HR 1.41; 95% CI 1.05-1.89; p=0.02).
Observational (n=14,173)
Yes
Are lower spirometry quality grades associated with increased mortality in a community-dwelling population?
Lower spirometry quality grades for FEV1 are independently associated with an increased risk of mortality in a community-dwelling population, suggesting they may provide prognostic value.
Effect estimate: HR 1.41 (95% CI 1.05-1.89)
p-value: p=0.02
Abstract Rationale Spirometry quality grades for forced expiratory volume in 1 second (FEV1) were established based on expert opinion of expected technical thresholds. These grades aid in pulmonary function test interpretation by categorizing the reliability of the values. Whether spirometry grades are associated with clinical outcomes is unknown. Methods We performed a retrospective secondary analysis of the National Health and Nutrition Examination Survey (NHANES). Cohorts between 2007-2011 were included. After exclusions, 14,173 subjects were included in the final analysis. Spirometry was performed according to ATS standards with rigorous training of spirometry technicians. A subject’s best FEV1 attempt was given a quality grade of A, B, C and D/F based on the usability of acceptability of the attempt. Subjects with grades D and F were combined due to sample size limitations. The NHANES dataset was linked to the National Death Index to adjudicate mortality. Time-to-event analysis using Cox Proportional Hazards was used to measure the association between spirometry grades and mortality. Univariable and multivariable analysis were performed, with covariates of age and FEV1 raw value in the multivariable model. Results Of the 14,173 subjects included, 9965 (70.3%) achieved grade A, 3029 (21.4%) achieved grade B, 845 (6.0%) achieved grade C, and 334 (2.4%) achieved grades D or F. The mean age for those achieving grade A was 44.0 (standard deviation (SD): 31.0-59.0) and for those receiving grades D/F was 52.0 year (SD: 35.0-65.0). The mean FEV1 in liters was 3.08 (SD: 0.90) for Grade A, 3.18 (SD: 0.92) for Grade B, 3.00 (SD: 0.97) for Grade C and 2.54 (0.89) for Grade D/F. In univariable time-to-event survival analysis, with Grade A FEV1 as comparator, subjects with Grade B had HR 1.15 (CI: 0.99-1.32, p = 0.07), Grade C had HR 1.54 (CI: 1.24-1.92, p = 0.001), and Grade D/F had HR 2.10 (CI: 1.57-2.81, p 0.0001). In multivariable analysis, Grade B had HR 1.19 (CI: 1.03-1.38, p = 0.02), Grade C had HR 1.30 (CI: 1.04-1.62, p = 0.02), and Grade D/F had HR 1.41 (CI: 1.05-1.89, p = 0.02). Conclusions In a community dwelling population, spirometry grades A or B are achieved in most subjects. Lower FEV1 spirometry grades are associated with increased risk of mortality and may provide prognostic value. This abstract is funded by: None
Russell et al. (Fri,) conducted a observational in Community dwelling population (n=14,173). Lower spirometry quality grades (B, C, D/F) vs. Grade A spirometry was evaluated on Mortality (HR 1.41, 95% CI 1.05-1.89, p=0.02). Lower FEV1 spirometry grades (D/F vs A) were associated with an increased risk of mortality in multivariable analysis (HR 1.41; 95% CI 1.05-1.89; p=0.02).