Abstract
BackgroundInterstitial lung disease (ILD) patients often have comorbid chronic ischemic heart disease (CIHD), which may worsen prognosis. Large-scale studies on long-term CIHD mortality trends in ILD patients are lacking. This study analyzes CIHD-related mortality trends in US adults with ILD from 1999 to 2023.MethodsCIHD-related mortality data were extracted from the CDC WONDER database for ILD patients aged ≥25 years. International Classification of Diseases, 10th Revision (ICD-10) codes J84.1, J84.8, J84.9 identified ILD, and code I25 identified CIHD. Age-adjusted mortality rates (AAMR), annual percentage change (APC), and average annual percentage change (AAPC) per 100,000 were calculated using Joinpoint regression.ResultsBetween 1999 and 2023, there were 92,779 CIHD-related deaths among U.S. decedents with interstitial lung disease (ILD, listed as an underlying or contributing cause of death in death certificates); this accounted for a substantial proportion of cardiovascular-related deaths in this decedent population. The overall AAMR showed a slight upward trend (AAPC=0.51%), but with significant nonlinearity: a decrease from 2003-2018 (APC=-1.29%), increased sharply from 2018 to 2021 (APC = 9.75%), with the increase concentrated during the COVID-19 pandemic years. The age-adjusted mortality rate rose modestly from 1.54 per 100,000 in 2018 to 1.60 in 2019 (+3.9%), then surged to 1.73 in 2020 (+8.1%) and peaked at 1.98 in 2021 (+14.5% from 2020). After 2021, mortality declined to 1.88 in 2023. Mortality was higher in men, non-Hispanic Whites, adults >85 years, and in southern and nonmetropolitan areas. Each subgroup showed a significant increase in mortality during 2020-2021, coinciding with the pandemic, while pre-pandemic trends were more gradual.ConclusionsCIHD-related mortality in ILD patients showed a fluctuating upward trend over 25 years, with a significant jump during the COVID-19 pandemic. This underscores the systemic impact of public health emergencies on cardiovascular health in vulnerable populations. Cardiovascular risk assessment and management should be integrated into routine ILD care, with tailored strategies for high-risk groups and regions.