SAT-749 Greek Nationwide Study of HypOPArathyroidism (The OPA study): Preliminary Data on Morbidity, Care Gaps and Treatment Efficacy

Abstract Disclosure: R.D. Paparodis: None. I. Androulakis: None. N.G. Angelopoulos: None. D.P. Askitis: None. A. Boniakos: None. A. Rizoulis: None. D. Zianni: None. G. Simeakis: None. D.T. Papadimitriou: None. S. Livadas: None. J.C. Jaume: None. Introduction: Hypoparathyroidism (HPT) is an uncommon endocrine condition with significant morbidity and complications (nephrolithiasis, nephrocalcinosis, chronic kidney disease, ectopic calcifications, arrhythmias, cardiovascular disease - CVD, osteoporosis). Conventional treatment is slowly substituted by recombinant parathyroid hormone (rPTH) replacement, which might be able to reduce disease complications. Despite these advances, a large portion of the affected patients remains inadequately assessed and cared for and fewer receive newer treatments. We designed the present study to characterize the Greek population with HPT with regard to the disease course, treatment and complications associated with each treatment strategy. Methods: We reviewed all cases of HPT followed in eight referral Hellenic Endocrine Network clinics scattered all over Greece, regarding the disease etiology, patients' gender, age at diagnosis, height and weight, duration of HPT, treatments used, serum albumin corrected and urine calcium (Ca) concentrations, PTH, renal function, development of nephrolithiasis, nephrocalcinosis, cardiovascular disease (CVD), cataracts and osteoporosis. Results: We collected data on 167 patients with HPT: 146 females (87.4%), n= 157 (94.0%) with post-surgical HPT (93.5%), n=7 (4.2%) with autoimmune and n=3 (1.8%) with unclear etiology of HPT. Mean age at diagnosis was 46.7±12.8 years old, BMI 29.0±6.1Kg/m2, and follow up was available for 10.2±7.1 years. Baseline Ca was 7.7±0.9mg/dl (n=31 patients with Ca <7mg/dl) and PTH was 13.1±12.0pg/ml. During the most severe hypocalcemia (Ca 7.3±0.7mg/dl, n=51 patients with Ca <7.0mg/dl) PTH was 11.0±6.7pg/ml. MDRD estimated GFR dropped from 99.3±22.7 at baseline to 87.7±26.9ml/min/1.73m2 at the end of follow up (p<0.05). Complications occurred in n=68 (40.7%) patients overall: nephrolithiasis n=26 (15.6 %), nephrocalcinosis n= 9 (5.4%), arrhythmias n= 16(9.5%), CVD events n=11 (6.6%), osteoporosis n=13 (7.8%), osteopenia n=24 (14.4%) and cataracts n=4/45 (8.9%). These were more common in patients with longer duration of the disease (p<0.05). Treatment with PTH analogs was initiated in n=22 (13.2%) patients with complications since 2019. No renal ultrasound was performed in n=39 (23.4%) and no 24hr urine collection in n=55 (32.9%). Conclusions: Hypoparathyroidism is a major cause of morbidity for affected patients and complications tend to cluster with time. In the largest study from Greece to date we note that patients require more intense follow up with regard to complications, while newer agents need to be better evaluated with regard to their ability to stabilize or improve important long-term outcomes, such as cardiovascular disease, renal function and metabolic bone health. Presentation: Saturday, July 12, 2025