Prevalence and Medical Costs of Intellectual Disabilities and Pervasive Developmental Disorder in Korea: Based on National Health Insurance Service Claims Data from 2007 to 2019

Objective@#We aimed to investigate the annual prevalence of intellectual disabilities (ID) and autism spectrum disorder employing claims data registered in Korean National Health Insurance Service. We also estimated the annual average of medical costs incurred from these disorders using same datasets. @*Methods@#In order to obtain the prevalence, we selected patients diagnosed with ID and pervasive and specific developmental disorders (PDD) from 2007 to 2019. The ensuing annual average of medical costs was also estimated from these patients. @*Results@#The annual prevalence of ID and PDD (per 100,000) between 2007 and 2019 ranged from 56.7 to 78.6 and from 22.0 to 44.6 respectively. Regarding the annual average of total medical expenditure per a patient, the expenditure of the ID group was higher than that of PDD throughout the years, as shown that the ID expenditure ranged from 769.7 to 1,501.2 US dollars as opposed to the PDD expenditure in the range of 312.5 to 570.7 US dollars. The further comparison in relation to income levels elaborated that the medical aid beneficiary group constitutes the highest one and the difference of the expenditure across the remaining income groups was not prominent although the very low group generally ranked the highest over the years. @*Conclusion@#The prevalence of ID and PDD constantly increased and the same trend was displayed in ensuing health expenditures throughout the period. This implies that increasing needs exist across these patients with regards to therapeutic interventions, thereby contributing to prioritizing medical policies on national perspectives.

Association between Thyroid Hormones, Apolipoprotein E, and Cognitive Function among Cognitively-Normal Elderly Dwellers

Objective@#The correlation among the thyroid-related hormones, Apolipoprotein E ε4 (APOE ε4) and cognitive function has been reported despite controversial results. This study was designed to investigate this correlation among cognitively-normal elderly dwellers. @*Methods@#This study assessed 507 cognitively normal individuals aged over 60 who underwent comprehensive hematological and neuropsychological assessments including the quantification of serum free thyroxine and thyroid stimulating hormone (TSH) as well as the Korean version of the Consortium Establish a Registry for Alzheimer’s disease. The Korean version of Geriatric Depression Scale was also employed to evaluate the severity of depression. Age, gender, education, and the presence of APOE ε4 were taken into account as covariates. @*Results@#There was a significant positive association between verbal fluency test (VFT), Word List Memory Test (WLMT), and Word List Recall Test (WLRT) score and serum TSH levels (p=0.007, 0.031, and 0.023 respectively). The further analysis adding the interaction between APOE ε4 and TSH level, however, revealed only VFT score was significantly influenced by this interaction (p=0.026). @*Conclusion@#Lower serum TSH levels had impacts on both semantic memory (VFT) and episodic memory (WLMT, WLRT) among cognitively-normal elderly, whereas the interaction of TSH and APOE ε4 influenced only the task of semantic memory (VFT) in this group.