Endocrine Abstracts

Introduction: Even though it is well known that long-term complications, such as renal insufficiency and brain calcifications can occur in patients with hypoparathyroidism (HPT), the risk of cardiovascular diseases still remains unclear.

Objective: To perform a systematic assessment of cardiovascular function in a well-characterized cohort of patients with HPT compared to population-based controls.

Methods: 133 patients with chronic HPT (disease duration >6 months) were included and systematically examined regarding cardiovascular comorbidities. All participants were assessed by blood pressure measurement, electrocardiogram (ECG), cardiac ultrasound and laboratory analyses. We performed 1:3 propensity score matching with individuals from the German population-based Study of Health in Pomerania (SHIP-TREND, n = 2682) for age, sex, body-mass-index, smoking status, diabetes mellitus, dyslipidemia and TSH. Group differences were tested with Wilcoxon signed rank sum test (continuous variables), McNemar-test (dichotomous variables) or Friedman’s Chi-Square test (categorical variables).

Results: Patients with HPT showed significantly higher diastolic blood pressure levels than controls (median 86 mmHg vs 78 mmHg, P < 0.01), whereas systolic blood pressure was comparable (126 mmHg vs 127 mmHg, P = 0.19). Intake of diuretics (24% vs 6%, P < 0.01), calcium channel blockers (13% vs 6%, P < 0.01), as well as angiotensin receptor antagonists (36% vs 27%, P < 0.01) was significantly more frequent in patients with HPT. QTc intervals were markedly prolonged in HPT patients (438 ms vs 423 ms, P < 0.01) in ECG. Interestingly, cardiac ultrasound revealed significantly lower interventricular septum thickness (0.8 cm vs 1.0 cm, P < 0.01), as well as lower E/A ratio (1.0 vs 1.1, P < 0.01) in HPT. Left ventricular ejection fraction was comparable between patients and controls (P = 0.05). Regarding valvular dysfunctions HPT patients less frequently presented with insufficiencies of the mitral (20% vs 40%, P < 0.01) and aortic (1% vs 7%, P < 0.01) valve, whereas aortic stenosis was more prevalent in HPT compared to controls (7% vs 1%, P < 0.01).

Conclusion: Here we report more frequent treatment with calcium channel blockers and angiotensin receptor agonists, as well as higher diastolic blood pressure in HPT patients compared to matched controls. Furthermore, QTc intervals remain prolonged in HPT despite established replacement therapy which should be taken into account when treating patients with compounds additionally prolonging QTc. Cardiac ultrasound revealed comparable left ventricular ejection fraction, thinner interventricular septum, as well as lower E/A ratio. Additionally, prevalence of aortic stenosis was higher in HPT, most likely due to valvular calcification. In general, HPT is not associated with striking cardiovascular disease burden in our cohort compared to matched controls.