Resolving the Paradox of Bidirectional LDL Dysregulation in Schizophrenia: Evidence for a Glial-Hematopoietic-Senescence Framework

Background and Rationale: Schizophrenia has long been linked to a lipid profile that resists straightforward interpretation. People in their first psychotic episode, especially those never exposed to antipsychotics, reliably show lower circulating low-density lipoprotein cholesterol (LDL-C) compared with healthy controls. As the illness persists and pharmacological treatment accumulates, however, LDL-C tends to climb, feeding into the sharply elevated cardiovascular mortality that shadows the disorder. This temporal paradox—an apparent inborn tendency toward low cholesterol giving way to treatment- and disease-driven dyslipidemia—has never been satisfactorily explained at a mechanistic level. Methods and Key Findings: To untangle this paradox, we carried out an integrative multi-omics investigation. MAGMA gene-based analysis applied to a large European LDL genome-wide association study identified thousands of associated genes, with particularly strong signals among lipid-regulatory and immune-related loci. Transcriptome-wide association studies built on GTEx v8 expression models revealed that LDL-associated genetic variants preferentially shape the expression of microglia and oligodendrocyte marker genes across brain tissues, with enrichment ratios of 1.50 and 1.39, respectively. Schizophrenia-associated genetics, examined in metabolic tissues, were instead most enriched for clonal hematopoiesis driver genes (ratio 1.22). When the two trait architectures were compared through gene-set enrichment analysis, they converged on pathways governing cellular senescence, complement activation, and cellular stress responses. Interpretation: These results ground a new Glial–Hematopoietic–Senescence (GHS) Pleiotropy Model. Genetic variation tied to LDL metabolism primarily disrupts cholesterol handling within brain glia, accounting for the intrinsic hypocholesterolemia of early-stage schizophrenia and the white-matter pathology that accompanies it. Schizophrenia polygenic risk, by contrast, fosters clonal hematopoiesis and systemic inflammation in peripheral tissues, propelling the later emergence of dyslipidemia and cardiovascular burden. Senescence-related processes sit at the center, acting as a bidirectional amplifier that links the two compartments. This compartmentalized framework resolves the long-standing LDL paradox in schizophrenia and points toward new strategies for precision cardiometabolic prevention in this vulnerable population. Keywords: schizophrenia, LDL cholesterol, pleiotropy, microglia, clonal hematopoiesis, senescence, inflammaging, transcriptome-wide association study