Serum calcium levels are associated with cognitive function in hypoparathyroidism: a neuropsychological and biochemical study in an Italian cohort of patients with chronic post-surgical hypoparathyroidism

Abstract

Purpose Hypoparathyroidism (HypoPT) is a rare endocrine disease and conventional therapy is based on calcium and vitamin D analogues. Conventional therapy does not restore calcium homeostasis and patients complain with neuropsychological symptoms, which have been evaluated with nonspecific self-administered questionnaires. This study aims to evaluate cognitive functions of patients with chronic post-surgical (PS)-HypoPT compared to a control population, using a standardized neuropsychological approach and evaluating the relationship with serum calcium (Alb-Ca). Methods Observational, monocentric study on 33 patients with PS-HypoPT and 24 controls, in whom biochemical testing and a standardized neuropsychological assessment by a trained psychologist were performed. Results In patients with PS-HypoPT, low Alb-Ca correlated with a worse performance on semantic memory abilities and executive function, as suggested by a significant inverse correlation between Alb-Ca and Trail Making Test A (TMT-A) scores (r = − 0.423; p = 0.014) and by a positive correlation with Semantic Fluency Test scores (SF)(r = 0.510; p = 0.002). PS-HypoPT patients with Alb-Ca ≤ 8.9 mg/dl had a significantly lower test performance compared with PS-HypoPT patients with Alb-Ca > 8.9 mg/dl, both at the TMT-A test (mean score: 34.53–18.55; p < 0.0001) and at SF test (mean score: 41.94–48.68; p = 0.01) and also a significantly lower test performance compared with control patients’ group at TMT-A (mean score: 34.53–25.5; p = 0.0057). Conclusions Patients with chronic PS-HypoPT in conventional therapy do not show a severe cognitive impairment; however, cognitive functions namely visuo-spatial attention, executive function and semantic memory appear to be modulated by Alb-Ca and impaired by its low levels.

Parathyroid Hormone (PTH)-Related Peptides Family: An Intriguing Role in the Central Nervous System

“…Moreover, a novel neuropsychological approach, using expert neuropsychologist-devised tests, has allowed the analysis of cognitive, executive, and attentive functions in patients with Hypoparathyroidism. Patients with both idiopathic and post-surgical Hypoparathyroidism present neuropsychological impairment, with a worse performance in these tests for the former and for patients with longer follow-up and lower calcium levels, as evaluated in studies by our group and others [9,10,81].…”

“…More recently, the clinical evidence of neuropsychological symptoms in patients affected by idiopathic and post-surgical hypoparathyroidism [9,10], lacking systemic PTH effects and the recently available human-recombinant PTH-substitutive therapy, has rekindled the interest in the possible effects of PTH and/or its related peptides on the CNS.…”

The Role of the Patient Partnership in Designing Research on Neuropsychiatric Issues in Hypoparathyroidism

“…Limited reports have documented impaired cognitive function in nonsurgical hypoparathyroid patients, including reduced inhibitory control or an inability to suppress a thought, action, or feeling or a lack of “self-control,” impairment in visuo-spatial functioning, and psychomotor retardation [ 6 ]. In postsurgical hypoparathyroidism, the scant available data are variable, with one small study of predominantly White women showing impaired cognition, particularly slowed processing speed [ 7 ], and another report not finding a difference from controls but demonstrating that lower serum calcium levels were associated with worse visuo-spatial attention, executive function, and semantic memory scores [ 8 ]. Integrating hypoparathyroid patients' points of view is necessary to ascertain whether more studies are needed with formally administered cognitive testing by trained neuropsychologists.…”