What is already known about this topic? Age of asthma onset differentiates patients in many ways. Remission is common in child-onset asthma, but seemingly less common in adult-onset asthma. Risk factors of asthma persistence from childhood to adulthood are well described.What does this article add to our knowledge? In this study, age at asthma diagnosis after 40 years was the strongest risk factor of asthma nonremission, and age at diagnosis had a higher association with nonremission than current patient age or time from diagnosis.How does this study impact current management guidelines? Age at asthma diagnosis should be highlighted in the guidelines as a key indicator of asthma prognosis. Adequate follow-up and research resource allocation should be provided for adult-onset, especially late adult-onset asthma.BACKGROUND: Child-onset asthma is known to remit with high probability, but remission in adult-onset asthma is seemingly less frequent. Reports of the association between remission and asthma age of onset up to late adulthood are scarce. OBJECTIVE: To evaluate the association between asthma remission, age at diagnosis and gender, and assess risk factors of nonremission. METHODS: In 2016, a random sample of 16,000 subjects aged 20 to 69 years from Helsinki and Western Finland were sent a FinEsS questionnaire. Physician-diagnosed asthma was categorized by age at diagnosis to early-(0-11 years), intermediate-(12-39 years), and late-diagnosed (40-69 years) asthma. Asthma remission was defined by not having had asthma symptoms and not having used asthma medication in the past 12 months. RESULTS: Totally, 8199 (51.5%) responded, and 879 reported physician-diagnosed asthma. Remission was most common in early-diagnosed (30.2%), followed by intermediate-diagnosed (17.9%), and least common in late-diagnosed asthma (5.0%)