The detection of factors associated with hospitalizations for asthma attacks should have a great value in the development of intervention strategies. However, these factors are unknown in Turkey. Our aim was to investigate the factors associated with hospital admissions by comparing hospitalized patients with the community control asthma patients and the relationships between serum eosinophilic cationic protein (ECP) levels and the disease severity. Eighty-one subjects hospitalized with asthma (69 women and 12 men) and 300 community control asthma patients (227 women and 73 men) were enrolled in this cross-sectional study. A questionnaire including detailed demographic and clinical data was compiled by all patients. Serum ECP levels were measured in 76, 14, and 9 patients of community control, hospitalized asthma patients, and healthy controls, respectively. Hospitalized patients were older and had longer asthma duration (p < 0.001). The significant risk factors for hospital admission for acute asthma attacks were previous severe asthma (odds ratio [OR], 12.26; 95% confidence interval [CI], 5.17-29.0), aspirin (acetylsalicylic acid) and nonsteroidal anti-inflammatory drug intolerance (OR, 3.63; 95% CI, 1.70-7.74), chronic rhinosinusitis (OR, 2.24; 95% CI, 1.16-4.33), lower educational level (OR, 2.24; 95% CI, 1.33-4.18), and lower atopy ratio (OR, 1.99; 95% CI, 1.13-3.50). These parameters were similar in patients who were hospitalized and in patients who had severe asthma of the community control. ECP levels were significantly higher in hospitalized and severe asthma patients compared with healthy controls. In conclusion, the factors associated with hospitalizations were advanced age, prolonged asthma duration, presence of severe asthma, "nonatopy," acetylsalicylic acid-nonsteroidal anti-inflammatory drug intolerance, sinusitis, and lower educational level. Further intervention strategies are needed to address these markers to prevent hospitalizations from asthma attacks.