ASSOCIATION OF WHITE BLOOD CELL AND PLATELET INDICES WITH BODY MASS INDEX AMONG FEMALE UNIVERSITY UNDERGRADUATES IN SRI LANKA

Abstract

Obesity is a significant health concern among young adults, yet its impact on haematological parameters in young individuals remains underexplored. The present study found that a higher body mass index (BMI) was linked to increased white blood cell (WBC) count and platelet indices, along with a decreased eosinophil percentage, suggesting obesity-related haematological alterations even in healthy undergraduates. This cross-sectional study was conducted among 91 healthy females aged 18-25 after obtaining ethical approval from the Ethics Review Committee of the Institute of Biology, Sri Lanka (ERC IOBSL 380/11/2024). Participants were required to complete a self-administered questionnaire to select healthy individuals without a diagnosed chronic illness. Participants were excluded if they smoked, consumed alcohol, were pregnant, recently ill, had haematological disorders, donated blood within the last six months, or used medications/supplements affecting haematological parameters. Anthropometric measurements were employed to calculate BMI. Height was recorded using a standard stadiometer, with participants standing upright, their heels, hips, and head aligned against the measuring surface. Body weight was assessed using a calibrated electronic scale. Participants were divided into four groups according to Asian BMI classification: underweight (BMI<18.5kg/m2), normal weight (BMI=18.5 22.9 kg/m2), overweight (BMI=23.0-24.9 kg/m2) and obese (BMI≥25.0 kg/m2). The full blood count analysis was performed using an automated haematology analyser (Mindray BC-20, Shenzhen, China). Correlation analysis was performed using Pearson or Spearman coefficients, with p-values < 0.05 considered statistically significant. Statistically significant positive correlations were observed between BMI and total WBC (r =0.434, p =0.000), absolute granulocyte count (r =0.362, p =0.000), platelet count (PLT) (r =0.326, p =0.002), and plateletcrit (PCT) (r =0.383, p =0.000), whereas eosinophil percentage showed a significantly negative association (r = -0.272, p =0.009). Several WBC and platelet indices, including absolute lymphocyte count (r =0.032, p =0.763), monocyte percentage (r = -0.187, p = 0.077), mean platelet volume (r = 0.002, p = 0.982), and platelet distribution width (r = 0.048, p = 0.653), did not demonstrate statistical significance with the BMI. Future research should explore causal relationships between BMI and haematological alterations in more diverse populations. Therefore, the present study contributes to understanding obesity induced haematological alterations and provides a basis for future longitudinal investigations.