Prevalence and Risk Factors of Vitamin D Deficiency in Children Aged 0–5 Years: A Cross-Sectional Study in Khairpur District, Sindh

Vitamin D insufficiency is a major public health concern among young children, leading to skeletal deformities and impaired immune function. Limited sunlight exposure, poor diet, and low socioeconomic status contribute significantly to its burden in developing regions. Objectives: To determine the prevalence, risk factors, clinical manifestations, and health outcomes of vitamin D deficiency in children aged 0–5 years in Sindh, and to develop evidence-based strategies for its prevention and management. Methods: This cross-sectional analytical study was conducted at Khairpur Medical College, Khairpur Mir’s, Sindh, over six months (September 2024–February 2025). A total of 500 children were assessed for serum vitamin D levels and categorized as deficient (<20 ng/mL), insufficient (20–30 ng/mL), or sufficient (>30 ng/mL). Data on sunlight exposure, dietary intake, and socioeconomic factors were collected. Clinical manifestations, including growth retardation, dental issues, muscle weakness, and respiratory problems, were documented. Statistical analysis employed chi-square and logistic regression tests. Results: Vitamin D deficiency was observed in 50% of participants, while 29% had insufficiency. Key predictors included inadequate sunlight exposure (<30 minutes/day), poor dietary intake (OR=5.6, p<0.001), and low socioeconomic status (OR=4.3, p=0.002). Rickets (32.7%), recurrent respiratory infections (30.9%), delayed tooth eruption (29.1%), and muscle weakness (27.3%) were common findings. Conclusions: Vitamin D deficiency is highly prevalent among children in Sindh, with significant clinical and health implications. Public health initiatives promoting vitamin D supplementation, nutrition education, and sunlight exposure are urgently needed.