Endocrine Abstracts

JOINT3786

Background: Hypoparathyroidism (HypoPT) is most often caused by complications following neck surgery, post-surgical HypoPT, but genetic or autoimmune causes are seen, called non-surgical HypoPT (Ns-HypoPT). Calcium is vital for the mineralization of the fetal skeleton. Studies have shown that inadequate managed maternal HypoPT may cause preterm labor, miscarriage and stillbirth. Patients with HypoPT often complain of impaired cognitive skills, i. e. confusion, brain fog and forgetfulness. Studies have found that HypoPT patients, regardless of etiology, have reduced executive functions, processing speed, visual – and auditory memory. However, the impact on education level are still unknown. We aimed to investigate birth complications and education level in patients with post-surgical HypoPT and Ns-HypoPT compared to controls from the background population.

Material and Methods: We conducted a case-finding study, identifying patients with postsurgical hypoparathyroidism between 1988-2012 and patients with Ns-HypoPT between 1977-2012. Patients with HypoPT were identified through the National Patient Registry on ICD-codes combined with the regional prescription database. Controls were randomly selected from the background population using the Danish Civil Registration System. These were matched by gender and year of birth (± 2 years), using the incidence-density sampling technique. From Statistics Denmark registers we received all relevant information including fertility, childbirth and educational status.

Results: 688 patients with post-surgical (88% female, median age 49 years, mean follow-up 8. 4 years)) and 180 patients with Ns-HypoPT were identified (53% females, 49. 7 years at time of follow-up, 21% genetically verified), and matched to 2604 controls. No differences in birth outcomes including length, weight, head-, abdominal circumference or placenta weight were seen. We found a trend towards a shorter gestational age among post-surgical patients, P = 0. 07. Fewer patients with post-surgical HypoPT (80%) and Ns-HypoPT (32%) have completed an education, defined as vocational/short or higher, compared to controls (88% and 43%, respectively), P < 0. 01. No differences in age when receiving a higher education were seen. Investigations on the level of education show that 50% of patients with NS-HypoPT have primary school as their highest completed education. This is opposite controls, where only 30% have primary school as their highest completed education. Grades in primary school are significantly lower among Ns-HypoPT patients compared to controls, this concerns both written and verbal grades, P < 0. 01. In conclusion, no differences in birth outcomes were found. However, it seems that patients with HypoPT have a lower educational level compared to controls and grades among patients with Ns-HypoPT are significantly lower than controls.