Serum 25-hydroxyvitamin D, vitamin D supplement and asthma control: The HUNT study. (March 2018)

• Record Type: Journal Article
• Authors: Brumpton, Ben M.; Langhammer, Arnulf; Henriksen, Anne H.; Romundstad, Pål R.; Chen, Yue; Camargo, Carlos A.; Mai, Xiao-Mei
• Is Part Of: Respiratory medicine. Volume 136(2018)
• Page Start: 65
• Page End: 70
• Publication Date: 2018-03
• Subjects: Asthma -- Epidemiology -- Vitamin-D; Chest -- Diseases -- Periodicals; Chest -- Diseases -- Great Britain -- Periodicals; Respiratory organs -- Diseases -- Periodicals; Respiratory Tract Diseases -- Periodicals; Appareil respiratoire -- Maladies -- Périodiques; Thorax -- Maladies -- Périodiques; Appareil respiratoire -- Maladies -- Traitement -- Périodiques; Electronic journals; 616.2
• DOI: 10.1016/j.rmed.2018.01.017
• Languages: English
• ISSNs: 0954-6111

Abstract

Abstract: Few studies have investigated the association between serum 25-hydroxyvitamin D (25[OH]D), vitamin D supplement and asthma control among adults. We aimed to examine whether low levels of serum 25(OH)D or not taking vitamin D supplement were associated with an increased risk of poorly controlled asthma among Norwegian adults with asthma. We used a definition of asthma control adapted from the Global Initiative for Asthma. We first examined cross-sectional associations between serum 25(OH)D (n = 806) or vitamin D supplement (n = 1179) and poorly controlled asthma. Next, among those with well controlled asthma at baseline, we examined prospective associations between serum 25(OH)D (n = 147) or vitamin D supplement (n = 208) and poorly controlled asthma at follow-up, approximately 11 years later. We estimated risk ratios (RR) and 95% confidence intervals (CI) with Poisson regression. The adjusted RR for poorly controlled asthma was 1.00 (95% CI, 0.89–1.13) for adults with serum 25(OH)D < 50 nmol/L in cross-sectional and 1.50 (95% CI, 0.46–4.95) in prospective analyses. The adjusted RR for poorly controlled asthma was 1.17 (95% CI 1.00–1.37) for non-users of vitamin D supplement in cross-sectional and 1.66 (95% CI 0.49–5.67) in prospective analyses. Our study did not show strong evidence that among adults with asthma, having a low serum 25(OH)D or being a non-user of vitamin D supplement was associated with an increased risk of poorly controlled asthma. Some point estimates indicated an increased risk, however our estimates were generally imprecise and further evidence is needed. Highlights: Few studies have investigated vitamin D, vitamin D supplement and asthma control. We examined both cross-sectional and prospective associations. Some point estimates indicated an increased risk, however estimates were imprecise. Overall, we did not find strong evidence of an association.