Burn Pit Exposure and Earlier Sleep Apnea Diagnosis in Vets

TOPLINE:

Among 17,064 US veterans (mean age, 40.2 years; 89.6% male; 58.3% with posttraumatic stress disorder [PTSD]), those with the highest burn pit smoke exposure (BPSE) (≥ 245 days) were diagnosed with sleep apnea (SA) about 2.5 years earlier than those with the lowest exposure, with median time to diagnosis of 8.8 years vs 11.1 years, respectively. Although BPSE was not associated with SA prevalence after adjustment (adjusted odds ratio [AOR]: 1.10, P = .058), the highest exposure quartile showed an adjusted hazard ratio (AHR) of 1.16 (95% CI, 1.10-1.22) for earlier SA diagnosis.

METHODOLOGY:

• Retrospective cohort study of 17,064 US veterans enrolled in the Airborne Hazards and Open Burn Pit Registry (AHOBPR) who had sleep study data recorded in the Veterans Health Administration electronic medical record.
• Cumulative BPSE was calculated via self-reported data from deployments after October 7, 2001, and categorized into quartiles: Q0 (zero exposure), Q1 (0-46 days), Q2 (46-118 days), Q3 (118-245 days), and Q4 (> 245 days).
• Sleep apnea severity was measured using the Apnea-Hypopnea Index (AHI) extracted from polysomnography (PSG) and home sleep apnea test (HSAT) reports using a validated natural language processing (NLP) algorithm with 92% sensitivity and 88% specificity.
• Logistic regression models and Cox proportional hazards models were used to evaluate the association between BPSE and SA, adjusting for age, body mass index (BMI), smoking status, PTSD, and Charlson Comorbidity Index.
• Time to SA diagnosis was calculated by subtracting the sleep study date from the last deployment date, with veterans diagnosed with SA before their last deployment day excluded from analysis (n = 153).

TAKEAWAY:

• Veterans in the highest BPSE quartile (> 245 days) demonstrated a dose-dependent association with earlier SA diagnosis, with an unadjusted HR of 1.76 (95% CI, 1.68-1.85) and an AHR of 1.16 (95% CI, 1.10-1.22) after adjusting for confounders.
• Association between the highest BPSE quartile and SA prevalence was not statistically significant after adjusting for confounding factors (AOR, 1.10; 95% CI, 1.00-1.21; P = .058).
• Traditional risk factors for SA, including obesity, male sex, age, and higher comorbidity burden, were associated with higher risk for SA in the adjusted analysis.

IN PRACTICE:

"Our findings suggest that higher BPSE is associated with earlier diagnosis of SA even after adjusting for many clinically relevant variables. However, BPSE was not associated with a higher prevalence of SA overall as measured by AHI from clinical sleep studies. Therefore, this study provides evidence that BPSE may be linked to earlier SA diagnosis in veterans," the study authors wrote.

SOURCE:

The study was led by Ritwick Agrawal, MD, MS, Lung Institute, Department of Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Huntington, New York, and Javad Razjouyan, PhD, Veterans Affairs Health Services Research and Development Center for Innovations in Quality, Effectiveness and Safety, Michael E. DeBakey VA Medical Center, Houston. It was published online in Medical Care.

LIMITATIONS:

The study relied on self-reported exposure data from AHOBPR, which introduces potential for recall bias. Although the NLP algorithm demonstrated high recall and specificity, its overall accuracy was in the range of 86%-87%. The lack of information on specific pollutants or intensity of exposure restricts the ability to identify the most harmful components of BPSE. Although the study adjusted for key confounders such as BMI and smoking status, residual confounding from other factors, such as socioeconomic status or sleep-related behaviors, cannot be ruled out. Because the study population was predominantly male, older, and had higher BMI, generalizability to other populations may be limited. DISCLOSURES: This study received support from seed funding provided by Baylor College of Medicine, Houston, Texas; National Institutes of Health, National Heart, Lung, and Blood Institute K25 funding (#:1K25HL152006-01) awarded to Javad Razjouyan, PhD; Airborne Hazards and Burn Pit Exposures (AHBPCE#FY 2024-002) awarded to Razjouyan; VHA-CSRD-GWI (I01CX002841-01) awarded to Razjouyan and Drew A. Helmer, MD, MS; US Department of Veterans Affairs Clinical Science Research and Development Career Development Award (# IK2CX002363-01A1) awarded to Melissa B. Jones, MD; the Center for Innovations in Quality, Effectiveness and Safety (CIN 13-413); and the Michael E. DeBakey VA Medical Center, Houston, Texas. Jones and Amir Sharafkhaneh, MD, PhD disclosed receiving study drug support for a VA CSR&D investigator-initiated trial (VA Career Development Award # IK2CX002363-01A1) from Acadia Pharmaceuticals. The remaining authors reported no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.