Long-term Effect of Steroid on Metabolic Diseases in Asthmatics

A. Inclusion criteria i. Adult asthmatics (over 18 years) who have maintained inhaled corticosteroid with or without systemic corticosteroid for more than 12 months before the index date in our Medical Center.

ii. At least 1 asthma diagnosis within 1 year before the first corticosteroid exposure date by asthma specialists at Ajou University Medical Center (AUMC, Suwon, South Korea) with informed consent.

iii. A high cumulative dose is defined as the dose of corticosteroids above the mean cumulative dose of corticosteroids prescribed during 1 year.

iv. The equivalent dose will use for calculating the mean cumulative dose of each inhaled corticosteroid inhaler or systemic corticosteroid prescribed.

v. Prescriptions within 365 days from the first prescription will be assumed to be continuous, and the cohort end date will be defined as the end of the continuous drug exposure.

B. Exclusion criteria i. Patients younger than 18 years ii. Patients younger than 50 years and males in high-risk population cohorts iii. Patients with osteoporosis or osteoporosis-related major fracture outcomes (pathological fracture due to osteoporosis, closed fracture of the femur, pelvis, and vertebral column) before the index date iv. Patients with corticosteroid-related outcomes (diabetes mellitus, hypertension, hyperlipidemia) before the index date (for secondary endpoint).