Relationship Between Air Pollution and Symptom-Diagnosis Based Visits in Primary Care
Introduction:Air pollution is associated with adverse health outcomes, but most evidence comes from hospital data. Primary care records may capture earlier and milder presentations. This study aimed to evaluate the association between monthly changes in air pollutants and primary health care visits, stratified by symptoms and diagnosis, particularly respiratory infections and non-specific complaints such as headache and fatigue.Materials and Methods:This retrospective observational study analyzed monthly visit counts from four family health centers located closest to an official air-quality monitoring station in Karatay, Konya, Türkiye, between April 2024 and April 2025. Outcomes were defined using ICD-10 codes for upper respiratory tract infections (URTI), lower respiratory tract infections (LRTI), headache, and malaise/fatigue. Monthly mean concentrations of PM2.5, PM10, O3, NO2, SO2, and CO were obtained from public monitoring data.Results:Respiratory visits increased during December 2024–January 2025, when pollutant levels peaked. Same-month analyses showed the strongest respiratory associations with SO2(URTI: p=0.005; LRTI: p<0.001) and CO (URTI: p=0.027, LRTI: p<0.001), while particulate matter was more consistently linked to LRTI (PM2.5: p=0.018, PM10: p=0.036). Headache visits were inversely associated with O3(p=0.039).Conclusion:Poorer air quality—particularly elevated SO2and CO—was associated with increased respiratory visits in primary care, while headache presentations showed an ozone-related pattern. Primary care data may support local service planning during pollution peaks.