URBAN-RURAL DISPARITIES IN CALCIUM AND VITAMIN D DEFICIENCY: A POPULATION-BASED STUDY IN FAISALABAD, PAKISTAN

Abstract

Vitamin D deficiency is a global public-health problem that remains widespread in South Asian countries, including Pakistan, despite abundant sunlight throughout the year. The present cross-sectional study was conducted to assess the prevalence of vitamin D and calcium deficiency and to evaluate complete blood count (CBC) parameters among urban and rural populations of Faisalabad, Pakistan. A total of 68 volunteers (34 urban and 34 rural; 35 males and 33 females; aged 20-50 years) were enrolled. Venous blood samples were collected and analysed for serum calcium, 25-hydroxyvitamin D (by enzyme-linked immunosorbent assay, ELISA) and CBC parameters, including haemoglobin (Hb), total leukocyte count (TLC), haematocrit (HCT), mean corpuscular volume (MCV), red blood cell count (RBC), platelets, mean corpuscular haemoglobin concentration (MCHC) and mean corpuscular haemoglobin (MCH). A structured questionnaire recorded dietary intake, sun exposure, physical activity and body mass index. Mean serum calcium was 8.59 ± 1.58 mg/dL in the 20-34-year group and 8.54 ± 1.77 mg/dL in the 35-50-year group, while mean vitamin D was 8.85 ± 2.96 ng/mL and 9.44 ± 4.67 ng/mL, respectively, indicating widespread deficiency (reference range 20-30 ng/mL). Males had significantly higher vitamin D than females (10.03 ± 4.69 vs. 8.17 ± 2.39 ng/mL; P = 0.0451). Most CBC parameters did not differ significantly between age groups, although MCH was significantly higher in the older group (P = 0.0426). Correlation analysis showed a significant positive association between calcium and vitamin D (P < 0.01) and between HCT and MCV (P < 0.01). Vitamin D and calcium deficiencies were highly prevalent in both urban and rural areas of Faisalabad, with females at greater risk. Despite ample sunshine, cultural practices, limited effective sun exposure and dietary factors appear to drive this deficiency, underscoring the need for routine screening and targeted public-health interventions.