Long-term complications of permanent hypoparathyroidism in adults: prevalence and associated factors

Patients with Chronic hypoparathyroidism (CHPT) receiving conventional treatment are exposed to several long-term complications including basal ganglia calcifications, posterior subcapsular cataract, kidney stones, and renal insufficiency. The aim of this study was to assess the prevalence and the associated factors of these complications in patients with CHPT.

We conducted a cross-sectional study including 58 patients with CHPT. All participants underwent physical examination, biochemical assessment (total serum calcium, serum phosphorus, serum albumin, intact-PTH, serum magnesium, 25-hydroxy-vitamin D, serum creatinine, thyroid stimulating hormone (TSH), and 24-hour urinary calcium), slit lamp examination, brain computed tomography scan (CT-scan), and renal ultrasound.

Participants had a mean age of 52.6 ± 16.4 years and a gender ratio (women/men) of 3.5. Fahr syndrome, cataract, urolithiasis, and renal failure were found in 55%, 62%, 12%, and 17% of cases, respectively. CHPT duration >15 years (Adjusted-OR = 43.1, 95-CI: 2.63-703.06, p = 0.008) and poor adherence to treatment (Adjusted-OR = 8.04, 95%-CI: 1.52-42.42, p = 0.014) were independently associated with the risk of Fahr syndrome. Age >55 years (adjusted-OR = 5.07, 95-CI: 1.10-23.42, p = 0.037), disease duration >15 years (adjusted-OR = 20.21, 95-CI: 1.54-265.84, p = 0.022), and magnesium level <0.8 mmol/l (adjusted-OR = 36.46, 95-CI: 3.75-354.08, p = 0.002) were independently associated with the risk of subcapsular cataract. Only hypercalciuria (Adjusted-OR = 21.27, 95-CI: 2.31-195.91, p = 0.007) was an independent risk factor for kidney stones. Renal failure was not associated with kidney stones (p = 1). However, creatinine clearance was negatively correlated with age (r = -0.784; p < 10^-3) and disease duration (r = -0.352; p = 0.007).

Our results revealed high prevalences of neurological, ocular, and renal complications in patients with CHPT and emphasized the importance of regular biological monitoring, therapeutic adjustments, screening, and adherence to treatment in the prevention of these complications.