Objective: This study aimed to determine the prevalence of asthma and allergic diseases in the province of Giresun and to evaluate their associations with demographic, geographic, and environmental factors using a two-stage population-based epidemiological design.

Materials and Methods: Conducted between March and November 2025, the study employed a two-stage cross-sectional survey based on the European Community Respiratory Health Survey (ECRHS). In Stage 1, 1,322 adults aged 20-44 years completed the ECRHS Stage 1 questionnaire to assess respiratory and allergic symptoms. In Stage 2, a random subsample of 131 participants completed the main ECRHS questionnaire to estimate prevalence. Narrow-definition allergy was defined as the presence of specific allergen-related respiratory or nasal symptoms, whereas broad-definition allergy included any self-reported allergic symptoms irrespective of particular triggers. Asthma and allergy definitions were based on standardized ECRHS criteria. Logistic regression analyses were performed to identify independent predictors of current asthma and allergic disease. Bias was minimized through random sampling, validated instruments, and standardized procedures.

Results: The prevalence of current asthma was 14.5% (95% CI: 8.6-20.4). Narrow-definition allergy was present in 57.3% of participants, and broad-definition allergy in 72.5%. Early childhood respiratory infections, shared-room exposure before age 5, and occupational respiratory symptoms were significantly associated with current asthma in univariate analyses. In multivariable models, pollen-triggered respiratory symptoms remained the only independent predictor of current asthma (OR = 10.22, p = 0.009). For narrow-definition allergy, animal-induced and pollen-induced atopic symptoms were significant predictors. Traditional demographic and lifestyle factors, including age, sex, smoking status, and family history, were not independently associated with asthma or allergy after multivariable adjustment.

Conclusion: Asthma/allergic diseases are highly prevalent in Giresun and appear to be predominantly associated with environmental allergen exposures rather than traditional demographic risk factors. The strong influence of pollen- and animal-related atopic symptoms underscores the role of regional ecological characteristics in shaping respiratory health and highlights the need for environmentally targeted public health strategies in similar settings.