Polygenic Overlap Detected for Schizophrenia, CVD Risk

FRIDAY, Sept. 29, 2023 (HealthDay News) -- For individuals with schizophrenia, there is a genetic propensity for smoking and a reduced risk for obesity, according to a study published online Sept. 27 in the American Journal of Psychiatry.

Linn Rødevand, Ph.D., from the University of Oslo in Norway, and colleagues analyzed recent genome-wide association study results to assess overlapping genetic architecture between schizophrenia and cardiovascular disease (CVD) risk factors. To estimate the number of shared variants, the bivariate causal mixture model was applied, and the conjunctional false discovery rate approach was used to pinpoint specific shared loci.

The researchers identified extensive genetic overlap between schizophrenia and CVD risk factors, especially smoking initiation and body mass index (BMI; 8,600 and 8,100 variants, respectively). Specific shared loci were identified between schizophrenia and BMI, waist-to-hip ratio, smoking initiation, systolic blood pressure, diastolic blood pressure, type 2 diabetes, lipids, and coronary artery disease (304, 193, 293, 294, 259, 147, 471, and 35, respectively). Mainly concordant effect directions were seen for schizophrenia risk loci shared with smoking initiation, while opposite effect directions were mainly seen for the risk loci shared with BMI. Mixed-effect directions were seen for overlapping loci with lipids, blood pressure, waist-to-hip ratio, type 2 diabetes, and coronary artery disease. Mapped genes expressed in brain tissue and immune cells were implicated in functional analyses.

"We revealed polygenic overlap between schizophrenia and CVD risk factors, particularly BMI and smoking," the authors write. "The results indicate an inherent propensity to smoking in individuals with schizophrenia."

Two authors disclosed ties to industry.

Abstract/Full Text