Type 2 Diabetes Mellitus Is Independently Associated With Decreased Neural Baroreflex Sensitivity

Objective: Impaired baroreflex function is an early indicator of cardiovascular autonomic imbalance. Patients with type 2 diabetes mellitus (T2D) have decreased baroreflex sensitivity (BRS), however, whether the neural and/or mechanical component of the BRS (nBRS and mBRS, respectively) is altered in those with high metabolic risk (HMR, impaired fasting glucose and/or metabolic syndrome) or with overt T2D, is unknown. We examined this in a community-based observational study, the Paris Prospective Study III (PPS3). Approach and Results: In 7626 adults aged 50 to 75 years, resting nBRS (estimated by low-frequency gain, from carotid distension rate and RR intervals [time intervals between successive R waves]) and mBRS were measured by high-precision carotid echotracking. The associations between overt T2D or HMR as compared with subjects with normal glucose metabolism (NGM) and nBRS or mBRS were quantified using multivariable linear regression analysis. There were 319 subjects with T2D (61±6 years, 77% male), 1450 subjects with HMR (60±6 years, 72% male), and 5857 subjects with NGM (59±6 years, 57% male). Compared with NGM subjects, nBRS was significantly lower in HMR subjects (β=−0.07 [95% CI, −0.12 to −0.01]; P =0.029) and in subjects with T2D (β=−0.18 [95% CI, −0.29 to −0.07]; P =0.002) after adjustment for confounding and mediating factors. Subgroup analysis suggests significant and independent alteration in mBRS only among HMR patients who had both impaired fasting glucose and metabolic syndrome. Conclusions: In this community-based study of individuals aged 50 to 75, a graded decrease in nBRS was observed in HMR subjects and patients with overt T2D as compared with NGM subjects.