Vitamin D Status in Children: Romania's National Vitamin D Screening Programme in Context of the COVID-19 Pandemic.

Background and objectives: Vitamin D deficiency affects bone health and immune function, especially in children. While universal screening is not cost-effective, targeted screening and supplementation strategies have proven effective. This study evaluates the effectiveness of Romania's National Vitamin D Screening Programme in detecting vitamin D deficiency in paediatric patients, while also accounting for the impact of the COVID-19 pandemic.

Materials and methods: This retrospective observational study assessed the effectiveness of Romania's National Vitamin D Screening Initiative in detecting vitamin D deficiency among children admitted to the Clinical Emergency Hospital for Children "Louis Țurcanu", Timișoara, from January 2018 to December 2024. Serum 25-hydroxyvitamin D levels were analysed in 3596 tested patients out of 22,353 total admitted patients, to evaluate trends from before, during, and after the COVID-19 pandemic. Patients aged 0-18 with at least one admission were included, regardless of diagnosis. Patients in ICU, surgical departments, non-Romanian citizens, and those with life-threatening conditions were excluded. Logistic regression analysis was used to assess programme impact and risk factors for vitamin D insufficiency.

Results: The study population had a mean age of 5.36 years, with 53.57% male patients. Patient admissions dropped significantly during pandemic years (mean of 2057 annually in 2020-2022 vs. 4045.5 in pre-/post-pandemic years). Vitamin D insufficiency (<20 ng/mL) peaked at 33.3% in 2020 and 32.5% in 2023, with lowest rates in 2019 (17.2%) and 2021 (16.5%). The National Screening Programme implementation resulted in 57.1% higher odds of vitamin D testing in 2023-2024 compared with 2018-2019 (adjusted OR = 1.571, 95% CI: 1.429-1.726, p < 0.001), with testing rates increasing from 12.6% to 17.5%. Age emerged as the strongest predictor of vitamin D insufficiency, with each additional year associated with 8-9% increased odds of deficiency.

Conclusions: The National Vitamin D Screening Programme significantly enhanced detection of vitamin D insufficiency in paediatric populations, despite pandemic-related disruptions. An optimal testing rate of approximately 17% was identified for balancing detection efficiency with resource utilisation. These findings underscore the need for sustained risk-based screening programmes and public health education initiatives to address vitamin D insufficiency in children, particularly in developing countries with limited healthcare resources.