Lysophosphatidic acid and apolipoprotein A1 predict increased risk of developing World Trade Center-lung injury: a nested case-control study

Abstract

Rationale: Metabolic syndrome, inflammatory and vascular injury markers measured in serum after World Trade Center (WTC) exposures predict abnormal FEV1. We hypothesized that elevated LPA levels predict FEV₁ < LLN.

Methods: Nested case-control study of WTC-exposed firefighters. Cases had FEV₁ < LLN. Controls derived from the baseline cohort. Demographics, pulmonary function, serum lipids, LPA and ApoA1 were measured.

Results: LPA and ApoA1 levels were higher in cases than controls and predictive of case status. LPA increased the odds by 13% while ApoA1 increased the odds by 29% of an FEV₁ < LLN in a multivariable model.

Conclusions: Elevated LPA and ApoA1 are predictive of a significantly increased risk of developing an FEV₁ < LLN.

Figure 1. Study Design/Timeline

Symptomatic subjects in the FDNY medical monitoring exam (MME) presented for subspecialty pulmonary evaluation (SPE). Subjects underwent outlined studies at MME and SPE respectively. Baseline Cohort met the listed inclusion criteria. Cases (N=62) and Controls (N=111) had all final model variables available.

Figure 2. Multi-Analyte Model as 3D Plot

Probability of developing World Trade Center-LI of both LPA and ApoA1 are represented when adjusting for the covariates of exposure, BMI at SPE, pre-9/11 FEV₁ % predicted, dyslipidemia, platelet and PMN count. Plots express probability isopleths for the development of World Trade Center-LI with all other covariates held constant.