Background: Post-surgical hypoparathyroidism (hypoPT) increases fatigue and seems to affect the risk of mortality. Hypoparathyroid patients on conventional treatment with calcium and vitamin D supplementation show a reduction of Quality of life (QoL). Cardiovascular autonomic neuropathy (CAN) is an impairment of the cardiovascular autonomic system and it represents a cause of increased mortality and fatigability. Recently, we have demonstrated that patient with chronic post-surgical hypoparathyroidism show an increased risk of CAN. No previous studies have investigated the association between CAN and QoL in hypoparathyroidism. Aim: We tested the hypothesis that CAN would be associated with impaired QOL measures in subjects with chronic post-surgical hypoparathyroidism. Study population and design: We enrolled 49 post-surgical hypoparathyroid patients treated with calcium and calcitriol. Subjects completed the RAND 36-Item Short Form (SF-36) Health Survey, a measure of health-related QOL covering eight domains of physical and mental health. QOL has also been evaluated using Fatigue score (version 4). CAN was assessed by heart rate (HR) response to deep breathing, HR response to the lying-to-standing test, HR response to the Valsalva maneuver and blood pressure response to standing. Participants were considered to have “early CAN” (EC) if they had one abnormal result in the HR tests and “definite CAN” (DC) with two or more abnormal results. Results: the prevalence of EC was 39% (n=19), the prevalence of DC was 39% (n=19), the prevalence of patients without CAN (WC) was 22% (n=11). Only DC subjects had a statistically significant lower fatigue score compared to WC(35.1±5.8 vs 44.4±4.6, P=0.004). These results have been confirmed after adjustment for age, calcium concentration, calcitriol and calcium supplementation (β:-9.31, P=0.004). No statistically significant differences between groups were found for mental and physical component summary scores. Role limitation due to physical problem represents the only domain that showed a significant reduction between groups (WC: 82.6±33.4, EC: 72.4±33.2, DC: 50±38.2, ANOVA P=0.044). Conclusion: definite CAN may represent a cause of impaired QoL in patient with chronic post-surgical hypoparathyroidism. The presence of cardiovascular autonomic neuropathy could explain the fatigue, a common complaint in patient with hypoparathyroidism.
