Anti-Sympathetic Ganglia Antibodies and Postural Blood Pressure in IDDM Subjects of Varying Duration and Patients at High Risk of Developing IDDM

We examined the sera of 94 subjects with insulindependent diabetes mellitus (IDDM) for the presence of complement-fixing sympathetic ganglia (CF-SG) antibodies. In a cross-sectional analysis (duration 0–43 yr), 22% had detectable CF-SG antibodies. Subjects at high risk for IDDM were also studied. Four groups were studied: group 1 (aged 4–64 yr) islet cell antibodypositive (ICA⁺) prediabetic subjects, 10 of 19 (53%) were CF-SG⁺ ; group 2 (aged 6–14 yr) ICA⁻ prediabetic subjects (first-degree relatives of IDDM subjects with either transient hyperglycemia, impaired oral glucose tolerance, and/or first-phase insulin release after intravenous glucose tolerance testing), 4 of 9 (44%) were CF-SG⁺ (2 of the 4 ICA⁻ CF-SG⁺ subjects have progressed to IDDM); group 3 (aged 1.5-43 yr) ICA⁺ IDDM subjects (≤1 yr duration) 6 of 10 (60%) were CF-SG⁺; and group 4 (aged 8–59 yr) ICA IDDM subjects (≤1 yr duration), 2 of 11 (18%) were CF-SG⁺. All groups had increased CF-SG compared with controls. Postural blood pressure and simultaneous CF-SG antibody measurements were performed in 28 IDDM subjects. The drop in systolic blood pressure was greater in the CF-SG⁺ subjects (P < .05), and the frequency of CF-SG was greater in the mean to – 2SD group (P < .03) when data were analyzed within mean ± 2SD of the normal blood pressure response.