Residential Environmental Composition and Risk of Acute Cellular Rejection After Heart Transplantation: A Multi-Scale...

Area of Science:

• Environmental Epidemiology
• Transplant Immunology
• Geographic Information Systems (GIS)

Background:

• Acute cellular rejection (ACR) post-heart transplantation is not fully understood, despite standard immunosuppression.
• Environmental exposures, particularly residential land-use composition, may influence immune activation and rejection risk.
• Previous research has predominantly focused on air pollution, neglecting the impact of local land-use patterns.

Purpose of the Study:

• To investigate the association between residential environmental composition and ACR risk in heart transplant recipients.
• To determine if these associations are dependent on the scale (buffer size) and specific land-use domains.
• To explore the role of localized environmental factors in transplant outcomes.

Main Methods:

• Retrospective single-center cohort study involving 30 heart transplant recipients and 267 biopsy observations.
• Quantification of residential land-use composition (trees, green space, roads, water, industrial land) within 300m, 500m, 700m, and 1000m buffers.
• Statistical analysis using clustered logistic regression, adjusting for time since transplantation and controlling for False Discovery Rate (FDR).

Main Results:

• Statistically robust associations with ACR were confined to the 300m buffer zone.
• Tree-dominant (OR 1.42) and industrial land exposure (OR 1.50) within 300m were independently associated with increased ACR odds.
• Associations were scale-dependent, with no significant findings beyond the 700m buffer; some nominal associations at 500m did not survive FDR correction.

Conclusions:

• Residential environmental composition is associated with ACR in a scale-dependent manner, primarily within the immediate surroundings (300m buffer).
• Localized exposures to tree-dominant and industrial land use may contribute to rejection risk after heart transplantation.
• Findings are exploratory and hypothesis-generating, highlighting the need for further research into environmental influences on transplant outcomes.