Thyroid Disease Is Associated with Higher Age-Related Macular Degeneration Risk: Results from a Meta-Analysis of Epidemiologic Studies

Abstract

Background: Although epidemiologic studies have suggested that thyroid disease may be a risk factor for age-related macular degeneration (AMD), this finding is still controversial. Objectives: The aim of this meta-analysis was to investigate whether an association exists between thyroid disease and medication and AMD in epidemiologic studies. Methods: We searched PubMed, EMBASE, and Google Scholar from their inception to March 2020 for cross-sectional, case-control and cohort studies that assessed thyroid function and AMD risk. Data from selected studies were extracted, and a meta-analysis was performed using fixed-effect or random-effect models. The statistical heterogeneity (I2) among studies and the possibility of publication bias were evaluated. If I2 > 50%, a significant heterogeneity existed among studies and a random effects model was used to calculate the pooled RR. Otherwise, a fixed-effects model was performed. Results: A total of 13 epidemiologic studies that consisted of 7 thyroid disease and 7 thyroid medication studies were included. Statistically significant heterogeneity was observed in the study results (I2 thyroid disease = 80.1%, I2 thyroid medication = 69.0%). A significant positive association was found between thyroid disease and AMD, with an overall relative risk (RR) of 1.25 (95% CI: 1.02, 1.54). However, there was no statistical association between thyroid medication and AMD risk (pooled RR 1.26 [95% CI 0.92-1.72]). Egger’s test indicated that there was no significant publication bias for thyroid disease (P=0.889) or thyroid medication (P = 0.226). Conclusions: Our findings indicate that thyroid disease is associated with higher AMD risk. Thyroid disease prevention strategies may have a significant effect on the prevention of AMD and warrant further evaluation.

Dose-response association of metformin use and risk of age-related macular degeneration among patients with type 2 diabetes mellitus: a population-based study

“…A Taiwan population-based study indicated that insomnia is an independent indicator of an increased risk of AMD ( Tsai et al, 2020 ). Thyroid disease is associated with an increased risk of AMD ( Xu et al, 2021 ).…”

Excessive Thyroid Hormone Signaling Induces Photoreceptor Degeneration in Mice

“…(3) TH signaling has been associated with human cone/retinal diseases. Population-based/patient-based studies have shown strong evidence for the association between elevated TH level in the circulation/hyperthyroidism and increased incidence of AMD (atrophic/dry AMD; Age-Related Eye Disease Study Research Group, 2000 ; Chaker et al, 2015 ; Gopinath et al, 2016 ; Chatziralli et al, 2017 ; Lin et al, 2018 ; Abdelkader and Abass, 2019 ; Farvardin et al, 2021 ; Xu et al, 2021 ; Hung et al, 2022 ; Li et al, 2022 ). Optical coherence tomography evaluation shows macular thinning in patients with thyroid-associated ophthalmopathy ( Sayın et al, 2016 ; Blum Meirovitch et al, 2017 ).…”

“…Excessive TH signaling has been shown to induce auditory defects/cochlear degeneration ( Ng et al, 2009b ) and cerebellum degeneration ( Peeters et al, 2013 ) in mice. More importantly, TH signaling has been linked to neurodegenerative conditions in humans, including Alzheimer’s disease ( Kalmijn et al, 2000 ; Ceresini et al, 2009 ) and age-related macular degeneration (AMD; Age-Related Eye Disease Study Research Group, 2000 ; Chaker et al, 2015 ; Gopinath et al, 2016 ; Chatziralli et al, 2017 ; Lin et al, 2018 ; Abdelkader and Abass, 2019 ; Farvardin et al, 2021 ; Xu et al, 2021 ; Hung et al, 2022 ; Li et al, 2022 ).…”

Thyroid Dysfunction as a Modifiable Risk Factor for Wet Type Age-Related Macular Degeneration

“…In this study, no statistical association was reported between thyroid medication and AMD risk, although they could not conduct subgroup analyses according to AMD type. 12 …”

“…Some recently performed studies have proposed that thyroid dysfunction may also be considered a modifiable risk factor for AMD. 9 10 11 12 In fact, thyroid dysfunction predisposes the individual to other risk factors such as dyslipidemia, atherosclerosis, and hypertension. Moreover, recent investigations in this regard have reported that the suppression of thyroid hormone signaling was associated with cone photoreceptors preservation in mouse models.…”