Temporal Trends of Hypovitaminosis D: A Population-Based Study of Cases Under 19 Years of Age

Abstract

There is a growing epidemic of hypovitaminosis D in the western hemisphere, however the exact incidence is not known. Additionally, vitamin D has been shown to be associated with atopic and infectious disorders. We aimed to determine the incidence of hypovitaminosis D in a population-based cohort, as well as the prevalence of other comorbidities. We performed a historical cohort study of residents under 19 years of age in Olmsted County, Minnesota, during a 16-year period from January 2, 2002 through December 31, 2017, using the Rochester Epidemiology Project. Using each patient’s first total 25-hydroxyvitamin D concentration less than 30.0 ng/mL, a patient was classified as having either a vitamin D deficiency (<20 ng/mL) or insufficiency (20.1-30.0 ng/mL). Comorbidities at that index date were abstracted from the medical record. The age-and sex-adjusted incidence (per 100,000 person-years) of vitamin D deficiency/insufficiency increased significantly each year from 31.3 (95%CI, 18.7-43.8) in 2002-2003 to 589.7 (95%CI, 535.7-643.6) in 2012-2013, stabilizing at 606.0 in 2014-2015 and 580.1 in 2016-2017. The overall age-adjusted incidence was significantly higher for females compared to males (388.2 (95%CI, 365.9-410.5) vs. 257.4 (95%CI 239.8-275.1), respectively). The prevalence of allergic rhinitis (31.6% vs. 25.9%) and atopic dermatitis (21.7% vs. 17.4%) were significantly higher among patients with a vitamin D insufficiency (N=1353) compared to those with deficiency (N=634). The incidence of hypovitaminosis D increased significantly during 2002 to 2012, with stabilization afterward. The association of hypovitaminosis D in atopic conditions may warrant further inquiry.