Handedness, insulin sensitivity and pancreatic B-cell function in Type 2 diabetes

Background Laterality is associated with various health conditions. No study has addressed the influence of handedness on Type 2 diabetes mellitus (T2DM) phenotype, including glucose homeostasis, glucose-lowering therapies and metabolic control. Methods Five hundred and seventy-six consecutive adult T2DM outpatients underwent homeostasis model assessment (HOMA) of pancreatic B-cell function (B), insulin sensitivity (S), hyperbolic product (B x S) and age-standardized B x S deficit. Right-handed patients (87.5%; RH; n = 504) had similar age, gender, diabetes duration and education than non-right-handed patients (12.5%; non-RH; n = 72). Results Non-RH were more insulin-sensitive: 66% (39%) vs. 52% (36%) [mean (1 sd); P = 0.0024] and had significantly higher B x S and lower age-adjusted B x S deficit: 35% (20%) vs. 26% (17%) and 1.08% (0.40%) vs. 1.32% (0.55%)/year (non-RH; P = 0.0005 and P < 0.0001, respectively). Conclusions Non-right-handed T2DM patients are more insulin-sensitive, have higher hyperbolic product and less age-standardized B x S deficit. These may modulate glucose-lowering therapy requirements and glycaemic control.