Excessive longitudinal FEV1 decline and risks to future health: a case-control study.

BACKGROUND

Accelerated loss of forced expiratory volume in 1 s (FEV(1)) in an individual is considered an indicator of developing lung disease.

METHODS

We investigated longitudinal FEV(1) slopes, calculated by simple linear regression, and adverse health outcomes after 10-30 years, among 1,428 chemical plant workers. Cases were defined by FEV(1) slopes below 5th percentile values for the cohort. Cases were matched with controls (107 pairs) for race, gender, smoking status, year of birth, age, height, and calendar year at first test. Matched pair statistics were used for comparisons.

RESULTS

Cases had a higher proportion, compared to controls, of diagnosis of COPD or emphysema (17.8% vs. 1.9%, P = 0.0002), medication use for respiratory diseases (24.3% vs. 4.7%, P < 0.0001), dyspnea (15% vs. 3.7%, P = 0.0042), and wheezing or rhonchi on examination (10.3% vs. 1.9%, P = 0.0225).

CONCLUSIONS

Chemical plant workers who experienced accelerated FEV(1) declines experienced four to nine times as many adverse health conditions over 10-30 years.