Cognitive Function in Individuals with Chronic Hypoparathyroidism-A Prospective Observational Study

Objective: "Brain fog" is a frequently reported, distressing experience among individuals with chronic hypoparathyroidism, characterized by reduced concentration and reduced ability to perform day-to-day tasks. However, evidence linking chronic hypoparathyroidism to cognitive impairment is limited and inconsistent. This study aimed to explore cognitive function in these patients using a validated neurocognitive test battery, compare results with a matched healthy control group, and analyze the frequency of cognitive impairment based on normative data. Methods: The participants' cognitive performance was tested using a cognitive test battery, including the Trail Making Test A/B, the Color-Word Interference Test, and the California Verbal Learning Test. These tests were used to evaluate the cognitive domains of "attention and processing speed," "verbal learning and memory, " and "executive function." In total, 30 individuals with hypoparathyroidism and 30 healthy controls were included. Results: 24 patients were women (80.0%), with a median age of 44.5 +/- 13.1 and a median disease duration of 8.7 years (+/- 5.3). Individuals with chronic hypoparathyroidism showed poorer cognitive performance in "attention and processing speed" (F(1,57) = 8.65, p = 0.005*, eta(2) = 0.13) compared to healthy controls. A significantly higher percentage of patients had cognitive deficits in both "attention and processing speed" (56.7% vs. 3.3%) and "executive function" (60.0% vs. 16.7%). Conclusions: This study provides evidence that cognitive dysfunction, particularly in "attention and processing speed" is common in chronic hypoparathyroidism. Recognizing cognitive impairment in these patients is crucial, especially when discussing workability. Neuropsychological training as an adjunct therapy strategy may be beneficial in managing these cognitive deficits.