Evaluation of the Relationship between Serum 25-Hydroxyvitamin D Levels and Pulmonary Functions in Adult Asthma

Aim: This study was aimed to determine the relationship between serum 25-hydroxyvitamin D [25(OH)D] levels and the pulmonary functions in adult asthma patients. Material and Methods: A total of 131 asthmatic patients’ general characteristics, asthma symptoms, pulmonary function test, asthma control test (ACT) scores, serum 25(OH)D levels, body weight, and height were recorded. Body mass indexes (BMIs) of the patients were calculated and World Health Organization criteria were used for the classification. Patients with serum 25(OH)D levels below 20 ng/mL were classified as having a deficiency, those with 21-29 ng/mL as having an insufficiency, and those with 30 ng/mL and above as having normal serum vitamin D levels. Results: The serum 25(OH)D levels of patients in the uncontrolled asthma group, according to the ACT score, were found to be lower than those of patients in the controlled group (p=0.002). It was determined that as the serum 25(OH)D levels of the patients increased, the ACT scores also increased significantly (r=0.280, p=0.001). Additionally it was found that each 1 ng/mL increase in 25(OH)D level was associated with an increase of 0.176 L in forced vital capacity (FVC). In addition it was determined that as the serum 25(OH)D levels increased, the patients’ FVCs also increased (OR=1.056, 95% CI=1.003-1.113, p=0.038). Although the change was not statistically significant (p=0.081), as serum 25(OH)D levels increased, the ACT scores also increased. Conclusion: Vitamin D insufficiency and deficiency were frequently found in adults with asthma and there was a relationship between vitamin D deficiency and pulmonary function. Amaç: Bu çalışmanın amacı, yetişkin astım hastalarında serum 25-hidroksivitamin D [25(OH)D] düzeyleri ile pulmoner fonksiyonlar arasındaki ilişkiyi saptamaktır. Gereç ve Yöntemler: Toplam 131 astım hastasının genel özellikleri, astım semptomları, solunum fonksiyon testi, astım kontrol testi (AKT) skorları, serum 25(OH)D seviyeleri, vücut ağırlığı ve boy uzunluğu verileri kayıt altına alınmıştır. Hastaların beden kütle indeksleri (BKİ) hesaplanmış ve sınıflandırma için Dünya Sağlık Örgütü kriterleri kullanılmıştır. Serum 25(OH)D seviyesi 20 ng/mL'nin altında olan bireyler D vitamini eksikliği, 21-29 ng/mL olanlar D vitamini yetersizliği ve 30 ng/mL ve üstü olanlar ise normal serum D vitamini düzeyi olarak sınıflandırılmıştır. Bulgular: AKT skoruna göre kontrolsüz astım grubundaki bireylerin serum 25(OH)D düzeyleri, kontrollü grupt