Geographic variation in the association between Hashimoto's thyroiditis and Papillary thyroid carcinoma, a meta-analysis.

PURPOSE: The association between papillary thyroid cancer (PTC) and Hashimoto's thyroiditis (HT) remains a matter of debate. Several genetic and environmental factors have been found to influence this association. Because of the variation in these factors among different populations, we conducted a country- and region-based meta-analysis to examine whether the geographic area influences this association. METHODS: We searched PubMed and Web of Science databases for original articles that investigated the association between HT and PTC from February 1955 to February 28, 2023. The included studies were stratified according to their country and region of origin. Various subgroup analyses were conducted. The primary outcome was the pooled relative risk (RR) and its 95% confidence interval (CI) for each region and country. RESULTS: Forty-six studies including a total of 93,970 participants met our inclusion criteria. They originated from 16 countries distributed in five regions. Significant variation was found among countries but not among regions. Upon analysis of all 46 included studies, countries were classified based on their RR and its 95% CI. Excluding countries with pooled sample sizes <500, Sri Lanka (RR 4.23, 95% CI 2.91-6.14), Poland (RR 3.16, 95% CI 2.79-3.57) and Japan (2.68, 2.14-3.36) showed the strongest association between HT and PTC while Greece (RR 1.06, 95% CI 1.00-1.13), Spain (RR 0.70, 95% CI 0.23-2.11), and Jordan (0.62, 0.32-1.32) showed no significant association. CONCLUSION: Our findings revealed a variation in the association between HT and PTC among countries but not among regions. The country-to-country variation could be due to certain genetic and/or environmental factors subject to geographic variation that influence this association. These findings may help guide health policies aiming to mitigate the risk of PTC in the HT population by helping identify high-risk and low-risk countries.

Serum IGF-1 to IGFBP-3 Molar Ratio: A Promising Diagnostic Tool for Growth Hormone Deficiency in Children.

BACKGROUND: The serum insulin-like growth factor-1 (IGF-1)/insulin-like growth factor binding protein-3 (IGFBP-3) ratio has various potential applications in growth hormone-related disorders. This study aimed to investigate the performance of the IGF-1/IGFBP-3 ratio, independently and in combination with serum IGF-1 and IGFBP-3, in the diagnosis of growth hormone deficiency (GHD) in children with short stature (SS). METHODS: A 7-year cross-sectional observational study was conducted on 235 children with SS. Participants with known disorders that may affect IGF-1 other than GHD were excluded. Participants were classified into GHD (n = 64) and non-GHD (n = 171) groups. GHD was defined as a slow growth rate (<25th percentile over 1 year) and suboptimal growth hormone (GH) response to 2 GH stimulation tests (peak GH < 6.25 ng/mL using the DiaSorin Liaison assay). The sensitivity and specificity of serum IGF-1, IGFBP-3, and IGF-1/IGFBP-3 molar ratio, independently and in various combinations, were determined. RESULTS: GHD was diagnosed in 27.2% of participants. Among all studied variables, a low serum IGF-1/IGFBP-3 ratio demonstrated the greatest sensitivity for GHD (87.5%), with a comparable specificity (83.0%). The combination of low serum IGF-1, IGFBP-3, and IGF-1/IGFBP-3 ratio demonstrated the greatest specificity for GHD (97.7%), whereas the combination of normal serum IGF-1, IGFBP-3, and IGF-1/IGFBP-3 ratio demonstrated the greatest specificity for a non-GHD cause of SS (100.0%). CONCLUSION: Our data suggest that the serum IGF-1/IGFBP-3 ratio is a useful marker for the diagnosis of GHD in children who do not have other disorders that may affect serum IGF-1 levels. Further large studies are needed to confirm the diagnostic utility of the serum IGF-1/IGFBP-3 ratio.