Telomere Length and Haematopoietic Reserve in Elderly Patients with Unexplained Cytopenias at the Lagos University Teaching Hospital

This study investigates the relationship between telomere length and haematopoietic reserve in elderly patients with unexplained cytopenias at the Lagos University Teaching Hospital, South West Nigeria, addressing the emerging role of biological ageing in haematopoietic failure in this population. Unexplained cytopenias in the elderly often remain diagnostically unclear after standard investigations, and telomere attrition has been proposed as an aetiological mechanism, yet Nigerian data on this relationship are absent. An analytical cross-sectional study recruited 80 elderly patients (above 65 years) with unexplained peripheral cytopenias after excluding malignant, nutritional, and autoimmune causes, and 40 elderly controls without cytopenias. Peripheral blood mononuclear cell telomere length was measured by quantitative PCR. Bone marrow cellularity, erythroid and myeloid colony-forming capacity using in-vitro progenitor assay, and plasma inflammatory markers were assessed. Patients with cytopenias had significantly shorter telomere lengths (mean T/S ratio 0.87 vs 1.32 in controls). Telomere length correlated positively with haematocrit, neutrophil count, and in-vitro progenitor colony counts. Clonal haematopoiesis of indeterminate potential (CHIP) mutations were identified in 21 percent of cytopenic elderly patients by targeted next-generation sequencing panel. Shorter telomere length predicted bone marrow hypocellularity independently of age. The study provides first Nigerian evidence linking telomere attrition to haematopoietic reserve in elderly cytopenias and recommends telomere length measurement as part of unexplained cytopenia workup in elderly patients. Keywords: telomere length, haematopoiesis, cytopenias, elderly, clonal haematopoiesis.