1
|
Tesfaye E, Getnet M, Anmut Bitew D, Adugna DG, Maru L. Brain functional connectivity in hyperthyroid patients: systematic review. Front Neurosci 2024; 18:1383355. [PMID: 38726033 PMCID: PMC11080614 DOI: 10.3389/fnins.2024.1383355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 04/05/2024] [Indexed: 05/12/2024] Open
Abstract
Introduction Functional connectivity (FC) is the correlation between brain regions' activities, studied through neuroimaging techniques like fMRI. It helps researchers understand brain function, organization, and dysfunction. Hyperthyroidism, characterized by high serum levels of free thyroxin and suppressed thyroid stimulating hormone, can lead to mood disturbance, cognitive impairment, and psychiatric symptoms. Excessive thyroid hormone exposure can enhance neuronal death and decrease brain volume, affecting memory, attention, emotion, vision, and motor planning. Methods We conducted thorough searches across Google Scholar, PubMed, Hinari, and Science Direct to locate pertinent articles containing original data investigating FC measures in individuals diagnosed with hyperthyroidism. Results The systematic review identified 762 articles, excluding duplicates and non-matching titles and abstracts. Four full-text articles were included in this review. In conclusion, a strong bilateral hippocampal connection in hyperthyroid individuals suggests a possible neurobiological influence on brain networks that may affect cognitive and emotional processing. Systematic Review Registration PROSPERO, CRD42024516216.
Collapse
Affiliation(s)
- Ephrem Tesfaye
- Department of Biomedical Sciences, Madda Walabu University Goba Referral Hospital, Bale-Robe, Ethiopia
| | - Mihret Getnet
- Department of Human Physiology, School of Medicine, College of Medicine and Health Science, University of Gondar, Gondar, Ethiopia
- Department of Epidemiology and Biostatistics, Institute of Public Health, College of Medicine and Health Science, University of Gondar, Gondar, Ethiopia
| | - Desalegn Anmut Bitew
- Department of Reproductive Health, Institute of Public Health, College of Medicine and Health Science, University of Gondar, Gondar, Ethiopia
| | - Dagnew Getnet Adugna
- Department of Anatomy, School of Medicine, College of Medicine and Health Science, University of Gondar, Gondar, Ethiopia
| | - Lemlemu Maru
- Department of Human Physiology, School of Medicine, College of Medicine and Health Science, University of Gondar, Gondar, Ethiopia
| |
Collapse
|
2
|
Yu ZW, Pu SD, Sun XT, Wang XC, Gao XY, Shan ZY. Impaired Sensitivity to Thyroid Hormones is Associated with Mild Cognitive Impairment in Euthyroid Patients with Type 2 Diabetes. Clin Interv Aging 2023; 18:1263-1274. [PMID: 37554512 PMCID: PMC10406107 DOI: 10.2147/cia.s413584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 07/28/2023] [Indexed: 08/10/2023] Open
Abstract
Purpose The prevalence of mild cognitive impairment (MCI) in patients with type 2 diabetes (T2D) is rapidly increasing. Thyroid hormones are key regulators of cognitive function in adults. The purpose of this study was to investigate the relationship between thyroid hormone sensitivity and MCI in euthyroid T2D patients. Patients and Methods A total of 400 euthyroid T2D patients were enrolled in this cross-sectional study, including 218 patients with normal cognition and 182 MCI patients. The Montreal Cognitive Assessment (MoCA) was used to evaluate cognitive function. The free triiodothyronine to free thyroxine (FT3/FT4) ratio was calculated as a measure of peripheral sensitivity to thyroid hormones; the thyroid-stimulating hormone index (TSHI), thyrotrophic thyroxine resistance index (TT4RI) and thyroid feedback quantile-based index (TFQI) were calculated as measures of central sensitivity to thyroid hormones. Linear regression analysis and logistic regression analysis were performed to explore the relationships between these indices of thyroid hormone sensitivity and the MoCA score and MCI, respectively. Results Compared with the normal cognitive function group, patients in the MCI group had higher TSHI, TT4RI and TFQI but a lower FT3/FT4 ratio (P<0.05). The MoCA score was positively correlated with the FT3/FT4 ratio but negatively correlated with TSHI, TT4RI and TFQI (P< 0.05). Multivariate logistic regression analysis showed that a low FT3/FT4 ratio and high TSHI, TT4RI and TFQI were independently associated with MCI (P<0.05). After adjustment for confounding factors, the odds ratio (OR) for the association between MCI and the highest tertile of the FT3/FT4 was 0.455 (95% CI: 0.264-0.785), for the highest tertile of TSHI, the OR was 2.380 (95% CI: 1.376-4.119), for the highest tertile of TT4RI, the OR was 2.342 (95% CI:1.353-4.054), and for the highest tertile of TFQI, the OR was 2.536 (95% CI: 1.466-4.387) (P< 0.05). Conclusion Impaired sensitivity to thyroid hormones is associated with MCI in euthyroid T2D patients.
Collapse
Affiliation(s)
- Zi-Wei Yu
- Department of Endocrinology and Metabolism and the Institute of Endocrinology, The NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, First Hospital of China Medical University, Shenyang, 110001, People’s Republic of China
| | - Sheng-Dan Pu
- Department of Endocrinology, First Affiliated Hospital of Harbin Medical University, Harbin, 150001, People’s Republic of China
| | - Xiao-Tong Sun
- Department of Endocrinology, First Affiliated Hospital of Harbin Medical University, Harbin, 150001, People’s Republic of China
| | - Xi-Chang Wang
- Department of Endocrinology and Metabolism and the Institute of Endocrinology, The NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, First Hospital of China Medical University, Shenyang, 110001, People’s Republic of China
| | - Xin-Yuan Gao
- Department of Endocrinology, First Affiliated Hospital of Harbin Medical University, Harbin, 150001, People’s Republic of China
| | - Zhong-Yan Shan
- Department of Endocrinology and Metabolism and the Institute of Endocrinology, The NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, First Hospital of China Medical University, Shenyang, 110001, People’s Republic of China
| |
Collapse
|
3
|
Muacevic A, Adler JR, Shukla S, Kumar S. Neuropsychiatric Manifestations of Thyroid Diseases. Cureus 2023; 15:e33987. [PMID: 36811059 PMCID: PMC9938951 DOI: 10.7759/cureus.33987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 01/20/2023] [Indexed: 01/21/2023] Open
Abstract
Thyroid disorders are known to cause neuropsychiatric manifestations. Various neuropsychiatric manifestations are depression, dementia, mania, and autoimmune Hashimoto encephalopathy. Numerous investigations carried out in the previous 50-60 years have been evaluated critically. The pathophysiology of neuropsychiatric symptoms of thyroid diseases is described in the current study and its link with autoimmune Hashimoto encephalopathy is also discussed. Furthermore, this paper also describes the association between thyroid-stimulating hormones and cognitive impairment. Hypothyroidism is associated with depression and mania, and hyperthyroidism is linked with dementia and mania. The association between Graves' disease and various mental disorders such as depressive and anxiety disorders is also discussed. The aim of this study is to review the relationship between various neuropsychiatric disorders and thyroid diseases. A literature search from the PubMed database to find various neuropsychiatric manifestations of thyroid disorders in the adult population was conducted. According to the review of the studies, cognitive impairment can result from thyroid disease. It has not been possible to demonstrate how hyperthyroidism can hasten the process of developing dementia. However, subclinical hyperthyroidism, thyroid-stimulating hormone (TSH) levels below the normal range, and high free thyroxine (T4) levels all raise the risk of dementia in the elderly. Additionally, the potential mechanisms underlying this association have been examined. A quick summary of the research on mania as a clinical symptom of hypothyroidism and its likely causes and pathogenesis is also reviewed. There is no dearth of evidence that describes various neuropsychiatric manifestation in thyroid disorders.
Collapse
|
4
|
Ye Y, Wang Y, Li S, Guo J, Ding L, Liu M. Association of Hypothyroidism and the Risk of Cognitive Dysfunction: A Meta-Analysis. J Clin Med 2022; 11:jcm11226726. [PMID: 36431204 PMCID: PMC9694203 DOI: 10.3390/jcm11226726] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 11/02/2022] [Accepted: 11/09/2022] [Indexed: 11/16/2022] Open
Abstract
Objectives: The purpose of this meta-analysis was to assess whether there is an association between hypothyroidism and the risk of cognitive dysfunction. Methods: PubMed, Cochrane Library, and Embase were searched for relevant studies published from database inception to 4 May 2022, using medical subject headings (MeSHs) and keywords. Results: Eight studies involving 1,092,025 individuals were included, published between 2010 and 2021. The pooled analysis showed that there was no association between hypothyroidism and cognitive dysfunction (OR = 1.13, 95% CI = 0.84−1.51, p = 0.426), including both all-cause dementia (OR = 1.04, 95% CI = 0.76−1.43, p = 0.809) and cognitive impairment (OR = 1.50, 95% CI = 0.68−3.35, p = 0.318). Neither overt hypothyroidism (OR = 1.19, 95% CI = 0.70−2.02, p = 0.525) nor subclinical hypothyroidism (OR = 1.04, 95% CI = 0.73−1.48, p = 0.833) was associated with cognitive dysfunction. Neither prospective cohort (OR = 1.08, 95% CI = 0.77−1.51, p = 0.673) nor cross-sectional studies (OR = 1.23, 95% CI = 0.63−2.42, p = 0.545) had any effect on the association. Interestingly, the risk of cognitive dysfunction was significantly increased in the group not adjusted for vascular comorbidity (OR = 1.47, 95% CI = 1.07−2.01, p = 0.017), while it was reduced in the adjusted group (OR =0.82, 95% CI = 0.79−0.85, p < 0.001). Conclusions: This meta-analysis shows that hypothyroidism was associated with a reduced risk of cognitive dysfunction after adjustment for vascular-disease comorbidities. More prospective observational studies are needed in the future to investigate the relationship between hypothyroidism and cognitive dysfunction.
Collapse
Affiliation(s)
| | | | | | | | - Li Ding
- Correspondence: (L.D.); (M.L.)
| | | |
Collapse
|
5
|
Đapić B, Schernhammer E, Haslacher H, Stögmann E, Lehrner J. No effect of thyroid hormones on 5-year mortality in patients with subjective cognitive decline, mild cognitive disorder, and Alzheimer's disease. J Neuroendocrinol 2022; 34:e13107. [PMID: 35213057 PMCID: PMC9286816 DOI: 10.1111/jne.13107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 01/28/2022] [Accepted: 02/08/2022] [Indexed: 11/30/2022]
Abstract
The present study aimed to investigate differences in circulating thyroid hormone levels, gender, education, depressive symptoms, and cognitive performance among patients with cognitive impairment, and also to examine their associations, as well as that of cognitive decline, with 5-year mortality. Between 1998 and 2017, a hospital-based, single-centre (Neurology Department of the General Hospital in Vienna, Austria), retrospective follow-up study enrolled 2102 patients with mild to severe cognitive impairment (grouped into subjective cognitive decline, mild cognitive impairment, and Alzheimer's disease). Cox proportional hazards models were used to calculate hazard ratios (HRs), with 95% confidence intervals (CIs), as well as to calculate stepwise adjustments for demographic variables (age, gender, and education), depressive symptoms (Geriatric Depression Scale, GDS-15), and neuropsychological abilities (four domains of a neuropsychological test battery of Vienna, NTVB). In univariate analyses, total triiodothyronine (TT3) levels differed significantly between Alzheimer's disease and mild cognitive impairment patients (pdiff = .001). No other differences in cognitive impairment subgroups with any of the measured thyroid hormones were observed. Furthermore, in multivariate models, circulating TT3 was not associated with mortality (multivariable-adjusted HR per unit increase in TT3 = 0.56; 95% CI = 0.29-1.07). In multivariate models, we observed significantly lower 5-year mortality among women (HR = 0.56; 95% CI = 0.43-0.73) and those who scored higher on any of the four domains of the NBTV (e.g., attention and perceptual speed, HR = 0.63; 95% CI = 0.54-0.72); we also observed significantly higher 5-year mortality among patients with depressive symptoms (HR per one point score increase in GDS-15 = 1.06; 95% CI = 1.02-1.10), regardless of cognitive impairment subgroup. Among patients with various degrees of cognitive impairment, we found no associations of thyroid hormone levels with 5-year mortality. Gender, neuropsychological abilities, and depressive symptoms were each significant predictors of 5-year mortality. These results suggest that a neurocognitive test performance could serve as an important predictor of 5-year mortality among patients with cognitive impairment, although further studies with a more complete adjustment for comorbidities are needed to confirm these findings.
Collapse
Affiliation(s)
- Blaž Đapić
- Department of NeurologyMedical University of ViennaViennaAustria
| | - Eva Schernhammer
- Department of EpidemiologyCenter for Public HealthMedical University of ViennaViennaAustria
| | - Helmuth Haslacher
- Department of Laboratory MedicineMedical University of ViennaViennaAustria
| | | | - Johann Lehrner
- Department of NeurologyMedical University of ViennaViennaAustria
| |
Collapse
|
6
|
Jurado-Flores M, Warda F, Mooradian A. Pathophysiology and Clinical Features of Neuropsychiatric Manifestations of Thyroid Disease. J Endocr Soc 2022; 6:bvab194. [PMID: 35059548 PMCID: PMC8765786 DOI: 10.1210/jendso/bvab194] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Indexed: 01/25/2023] Open
Abstract
Thyroid hormones (TH) have a cardinal role in the development of the central nervous system during embryogenesis and early infancy. However, the TH-responsive genes in the developing brain cease to respond to TH in adulthood. Nevertheless, thyroid dysfunction in adults is commonly associated with a host of cognitive and psychiatric problems. Cognitive decline, dysphoria, and depression are common manifestations of overt hypothyroidism while hyperthyroidism can cause agitation, acute psychosis, and apathy, especially in older people. Whereas levothyroxine treatment can reverse dementia in the setting of hypothyroidism, the effect of levothyroxine on depressive symptoms in subjects with subclinical hypothyroidism is controversial. The use of supraphysiologic doses of TH to treat depression refractory to antidepressant remains a viable therapeutic tool with the caveat that excessive doses of thyroid hormone to treat depression may have potentially damaging effects on other organ systems. The present communication describes the pathophysiology of neuropsychiatric manifestations of thyroid disease, including changes in neurotransmission, alterations in neuronal or glial cell gene expression, blood-brain barrier dysfunction, increased risk of cerebrovascular disease, and occasionally cerebral inflammatory disease in the context of autoimmune thyroid disease. Elucidating the molecular mechanisms of TH effect on cerebral tissue will help identify novel therapeutic targets for managing people with neuropsychiatric disorders.
Collapse
Affiliation(s)
- Marilu Jurado-Flores
- Division of Endocrinology, Department of Medicine, University of Florida College of Medicine, Jacksonville, FL 32209, USA
| | - Firas Warda
- Division of Endocrinology, Department of Medicine, University of Florida College of Medicine, Jacksonville, FL 32209, USA
| | - Arshag Mooradian
- Division of Endocrinology, Department of Medicine, University of Florida College of Medicine, Jacksonville, FL 32209, USA
| |
Collapse
|
7
|
Khaleghzadeh-Ahangar H, Talebi A, Mohseni-Moghaddam P. Thyroid Disorders and Development of Cognitive Impairment: A Review Study. Neuroendocrinology 2022; 112:835-844. [PMID: 34963121 DOI: 10.1159/000521650] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 12/22/2021] [Indexed: 11/19/2022]
Abstract
Dementia is a neurological disorder that is spreading with increasing human lifespan. In this neurological disorder, memory and cognition are declined and eventually impaired. Various factors can be considered as the background of this disorder, one of which is endocrine disorders. Thyroid hormones are involved in various physiological processes in the body; one of the most important of them is neuromodulation. Thyroid disorders, including hyperthyroidism or hypothyroidism, can affect the nervous system and play a role in the development of dementia. Despite decades of investigation, the nature of the association between thyroid disorders and cognition remains a mystery. Given the enhancing global burden of dementia, the principal purpose of this study was to elucidate the association between thyroid disturbances as a potentially modifiable risk factor of cognitive dysfunction. In this review study, we have tried to collect almost all of the reported mechanisms demonstrating the role of hypothyroidism and hyperthyroidism in the pathogenesis of dementia.
Collapse
Affiliation(s)
- Hossein Khaleghzadeh-Ahangar
- Department of Physiology, School of Medicine, Babol University of Medical Sciences, Babol, Iran
- Immunoregulation Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
| | - Anis Talebi
- Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran
| | - Parvaneh Mohseni-Moghaddam
- Department of Physiology, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| |
Collapse
|
8
|
Marouli E, Yusuf L, Kjaergaard AD, Omar R, Kuś A, Babajide O, Sterenborg R, Åsvold BO, Burgess S, Ellervik C, Teumer A, Medici M, Deloukas P. Thyroid Function and the Risk of Alzheimer's Disease: A Mendelian Randomization Study. Thyroid 2021; 31:1794-1799. [PMID: 34847795 DOI: 10.1089/thy.2021.0321] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Background: Observational studies suggest an association between thyroid function and risk of dementia, but the causality and direction of these effects are unclear. We aim to test whether genetically predicted variation within the normal range of thyroid function and hypothyroidism is causally associated with the risk of Alzheimer's disease (AD). Methods: Mendelian randomization (MR) analyses using genetic instruments are associated with normal range thyrotropin (TSH) and free thyroxine (fT4) levels. Secondary analyses included investigation of the role of hypothyroidism. Bidirectional MR was conducted to address the presence of a potential reverse causal association. Summary statistics were obtained from the ThyroidOmics Consortium involving up to 119,715 individuals and the latest AD genome-wide association study data including up to 71,880 cases. Results: MR analyses show an association between increased genetically predicted normal range TSH levels and a decreased risk of AD (p = 0.02). One standard deviation increased normal range TSH levels were associated with a decreased risk of AD in individuals younger than 50 years old (p = 0.04). There was no evidence for a causal association between fT4 (p = 0.54) and AD. We did not identify any effect of the genetically predicted full range TSH levels (p = 0.06) or hypothyroidism (p = 0.23) with AD. Bidirectional MR did not show any effect of genetic predisposition to AD on TSH or fT4 levels. Conclusions: This MR study shows that increased levels of genetically predicted TSH within the normal range and in younger individuals are associated with a decreased risk of AD. We observed a marginal association between genetically predicted full range TSH and AD risk. There was no evidence for an effect between genetically predicted fT4 or hypothyroidism on AD. Future studies should clarify the underlying pathophysiological mechanisms.
Collapse
Affiliation(s)
- Eirini Marouli
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Lina Yusuf
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Alisa D Kjaergaard
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark
| | - Rafat Omar
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Aleksander Kuś
- Department of Internal Medicine and Endocrinology, Medical University of Warsaw, Warsaw, Poland
| | - Oladapo Babajide
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Rosalie Sterenborg
- Department of Internal Medicine, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
- Academic Center for Thyroid Diseases, Department of Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Bjørn O Åsvold
- K.G. Jebsen Center for Genetic Epidemiology, Department of Public Health and Nursing, NTNU, Norwegian University of Science and Technology, Trondheim, Norway
- Department of Endocrinology, Clinic of Medicine, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway
| | - Stephen Burgess
- MRC Biostatistics Unit, University of Cambridge, Cambridge, United Kingdom
- Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, United Kingdom
| | - Christina Ellervik
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA
- Department of Laboratory Medicine, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Alexander Teumer
- Institute for Community Medicine, University Medicine Greifswald, Greifswald, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany
| | - Marco Medici
- Department of Internal Medicine, Academic Center for Thyroid Diseases, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Panos Deloukas
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| |
Collapse
|
9
|
van Vliet NA, van Heemst D, Almeida OP, Åsvold BO, Aubert CE, Bae JB, Barnes LE, Bauer DC, Blauw GJ, Brayne C, Cappola AR, Ceresini G, Comijs HC, Dartigues JF, Degryse JM, Dullaart RPF, van Eersel MEA, den Elzen WPJ, Ferrucci L, Fink HA, Flicker L, Grabe HJ, Han JW, Helmer C, Huisman M, Ikram MA, Imaizumi M, de Jongh RT, Jukema JW, Kim KW, Kuller LH, Lopez OL, Mooijaart SP, Moon JH, Moutzouri E, Nauck M, Parle J, Peeters RP, Samuels MH, Schmidt CO, Schminke U, Slagboom PE, Stordal E, Vaes B, Völzke H, Westendorp RGJ, Yamada M, Yeap BB, Rodondi N, Gussekloo J, Trompet S. Association of Thyroid Dysfunction With Cognitive Function: An Individual Participant Data Analysis. JAMA Intern Med 2021; 181:1440-1450. [PMID: 34491268 PMCID: PMC8424529 DOI: 10.1001/jamainternmed.2021.5078] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
IMPORTANCE In clinical guidelines, overt and subclinical thyroid dysfunction are mentioned as causal and treatable factors for cognitive decline. However, the scientific literature on these associations shows inconsistent findings. OBJECTIVE To assess cross-sectional and longitudinal associations of baseline thyroid dysfunction with cognitive function and dementia. DESIGN, SETTING, AND PARTICIPANTS This multicohort individual participant data analysis assessed 114 267 person-years (median, 1.7-11.3 years) of follow-up for cognitive function and 525 222 person-years (median, 3.8-15.3 years) for dementia between 1989 and 2017. Analyses on cognitive function included 21 cohorts comprising 38 144 participants. Analyses on dementia included eight cohorts with a total of 2033 cases with dementia and 44 573 controls. Data analysis was performed from December 2016 to January 2021. EXPOSURES Thyroid function was classified as overt hyperthyroidism, subclinical hyperthyroidism, euthyroidism, subclinical hypothyroidism, and overt hypothyroidism based on uniform thyrotropin cutoff values and study-specific free thyroxine values. MAIN OUTCOMES AND MEASURES The primary outcome was global cognitive function, mostly measured using the Mini-Mental State Examination. Executive function, memory, and dementia were secondary outcomes. Analyses were first performed at study level using multivariable linear regression and multivariable Cox regression, respectively. The studies were combined with restricted maximum likelihood meta-analysis. To overcome the use of different scales, results were transformed to standardized mean differences. For incident dementia, hazard ratios were calculated. RESULTS Among 74 565 total participants, 66 567 (89.3%) participants had normal thyroid function, 577 (0.8%) had overt hyperthyroidism, 2557 (3.4%) had subclinical hyperthyroidism, 4167 (5.6%) had subclinical hypothyroidism, and 697 (0.9%) had overt hypothyroidism. The study-specific median age at baseline varied from 57 to 93 years; 42 847 (57.5%) participants were women. Thyroid dysfunction was not associated with global cognitive function; the largest differences were observed between overt hypothyroidism and euthyroidism-cross-sectionally (-0.06 standardized mean difference in score; 95% CI, -0.20 to 0.08; P = .40) and longitudinally (0.11 standardized mean difference higher decline per year; 95% CI, -0.01 to 0.23; P = .09). No consistent associations were observed between thyroid dysfunction and executive function, memory, or risk of dementia. CONCLUSIONS AND RELEVANCE In this individual participant data analysis of more than 74 000 adults, subclinical hypothyroidism and hyperthyroidism were not associated with cognitive function, cognitive decline, or incident dementia. No rigorous conclusions can be drawn regarding the role of overt thyroid dysfunction in risk of dementia. These findings do not support the practice of screening for subclinical thyroid dysfunction in the context of cognitive decline in older adults as recommended in current guidelines.
Collapse
Affiliation(s)
- Nicolien A van Vliet
- Department of Internal Medicine, Section of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, the Netherlands
| | - Diana van Heemst
- Department of Internal Medicine, Section of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, the Netherlands
| | - Osvaldo P Almeida
- Medical School, University of Western Australia, Perth, Western Australia, Australia.,Western Australian Centre for Health and Ageing, University of Western Australia, Perth, Western Australia, Australia
| | - Bjørn O Åsvold
- K.G. Jebsen Center for Genetic Epidemiology, Department of Public Health and Nursing, NTNU, Norwegian University of Science and Technology, Trondheim, Norway.,Department of Endocrinology, Clinic of Medicine, St Olav's Hospital, Trondheim University Hospital, Trondheim, Norway.,HUNT Research Center, Department of Public Health and Nursing, NTNU, Norwegian University of Science and Technology, Levanger, Norway
| | - Carole E Aubert
- Department of General Internal Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.,Institute of Primary Health Care (BIHAM), University of Bern, Bern, Switzerland.,Center for Clinical Management Research, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan.,Institute for Healthcare Policy and Innovation, University of Michigan, Ann Arbor
| | - Jong Bin Bae
- Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Linda E Barnes
- Department of Public Health and Primary Care, Cambridge Institute of Public Health, University of Cambridge, Cambridge, United Kingdom
| | - Douglas C Bauer
- Division of General Internal Medicine, School of Medicine, University of California, San Francisco
| | - Gerard J Blauw
- Department of Internal Medicine, Section of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, the Netherlands
| | - Carol Brayne
- Department of Public Health and Primary Care, Cambridge Institute of Public Health, University of Cambridge, Cambridge, United Kingdom
| | - Anne R Cappola
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia
| | - Graziano Ceresini
- Department of Medicine and Surgery, University of Parma, Unit of Internal Medicine and Oncological Endocrinology, University Hospital of Parma, Parma, Italy
| | - Hannie C Comijs
- Department of Psychiatry, Amsterdam Public Health research institute, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands.,GGZ inGeest Specialized Mental Health Care, Research and Innovation, Amsterdam, the Netherlands
| | - Jean-Francois Dartigues
- UMR 1219, Bordeaux Population Health Research Center, Inserm, University of Bordeaux, Bordeaux, France
| | - Jean-Marie Degryse
- Department of Public Health and Primary Care, Katholieke Universiteit Leuven, Leuven, Belgium.,Institute of Health and Society, Université catholique de Louvain, Brussels, Belgium
| | - Robin P F Dullaart
- Division of Endocrinology, Department of Internal Medicine, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Marlise E A van Eersel
- University Center for Geriatric Medicine, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Wendy P J den Elzen
- Department of Clinical Chemistry and Laboratory Medicine, Leiden University Medical Center, Leiden, the Netherlands.,Atalmedial Diagnostics Centre, Amsterdam, the Netherlands.,Department of Clinical Chemistry, Amsterdam UMC, Amsterdam, the Netherlands
| | - Luigi Ferrucci
- Longitudinal Studies Section, Translational Gerontology Branch, Harbor Hospital, Baltimore, Maryland.,National Institute on Aging NIA-ASTRA Unit, Baltimore, Maryland
| | - Howard A Fink
- Geriatric Research Education and Clinical Center, VA Healthcare System, Minneapolis, Minnesota.,Department of Medicine, University of Minnesota, Minneapolis
| | - Leon Flicker
- Medical School, University of Western Australia, Perth, Western Australia, Australia.,Western Australian Centre for Health and Ageing, University of Western Australia, Perth, Western Australia, Australia
| | - Hans J Grabe
- Department of Psychiatry and Psychotherapy, University Medicine Greifswald, Greifswald, Germany.,German Center for Neurodegenerative Diseases (DZNE), Site Rostock/Greifswald, Germany
| | - Ji Won Han
- Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Catherine Helmer
- UMR 1219, Bordeaux Population Health Research Center, Inserm, University of Bordeaux, Bordeaux, France
| | - Martijn Huisman
- Department of Epidemiology and Biostatistics, Amsterdam Public Health Research Institute, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands.,Department of Sociology, VU University Amsterdam, Amsterdam, the Netherlands
| | - M Arfan Ikram
- Department of Epidemiology, Erasmus MC, Rotterdam, the Netherlands
| | - Misa Imaizumi
- Department of Clinical Studies, Radiation Effects Research Foundation, Hiroshima and Nagasaki, Japan
| | - Renate T de Jongh
- Department of Internal Medicine and Endocrinology, Amsterdam UMC, Amsterdam, the Netherlands
| | - J Wouter Jukema
- Department of Cardiology, Leiden University Medical Center, Leiden, the Netherlands.,Netherlands Heart Institute, Utrecht, the Netherlands
| | - Ki Woong Kim
- Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, South Korea.,Department of Brain and Cognitive Science, Seoul National University College of Natural Sciences, Seoul, South Korea.,Department of Psychiatry, Seoul National University, College of Medicine, Seoul, South Korea
| | - Lewis H Kuller
- Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Oscar L Lopez
- Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Simon P Mooijaart
- Department of Internal Medicine, Section of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, the Netherlands
| | - Jae Hoon Moon
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Elisavet Moutzouri
- Department of General Internal Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.,Institute of Primary Health Care (BIHAM), University of Bern, Bern, Switzerland
| | - Matthias Nauck
- Institute of Clinical Chemistry and Laboratory Medicine, University Medicine Greifswald, Greifswald, Germany.,DZHK (German Centre for Cardiovascular Research), partner site, Greifswald, Germany
| | - Jim Parle
- Institute of Clinical Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Robin P Peeters
- Department of Internal Medicine, Erasmus MC, Rotterdam, the Netherlands.,Academic Center for Thyroid Diseases, Erasmus MC, Rotterdam, the Netherlands
| | - Mary H Samuels
- Division of Endocrinology, Diabetes and Clinical Nutrition, Department of Medicine, Oregon Health & Science University, Portland
| | - Carsten O Schmidt
- Department of Radiology, University Medicine Greifswald, Greifswald, Germany
| | - Ulf Schminke
- Department of Neurology, University Medicine Greifswald, Greifswald, Germany
| | - P Eline Slagboom
- Department of Biomedical Data Sciences, Section of Molecular Epidemiology, Leiden University Medical Center, Leiden, the Netherlands.,Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Eystein Stordal
- Namsos Hospital, Nord-Trøndelag Hospital Trust, Namsos, Norway.,Department of Mental Health, NTNU, Norwegian University of Science and Technology, Trondheim, Norway
| | - Bert Vaes
- Department of Public Health and Primary Care, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Henry Völzke
- Institute for Community Medicine, University Medicine Greifswald, Greifswald, Germany
| | - Rudi G J Westendorp
- Department of Internal Medicine, Section of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, the Netherlands.,Department of Public Health, Section of Epidemiology, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Michiko Yamada
- Department of Clinical Studies, Radiation Effects Research Foundation, Hiroshima and Nagasaki, Japan
| | - Bu B Yeap
- Medical School, University of Western Australia, Perth, Western Australia, Australia.,Department of Endocrinology and Diabetes, Fiona Stanley Hospital, Western Australia, Australia
| | - Nicolas Rodondi
- Department of General Internal Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.,Institute of Primary Health Care (BIHAM), University of Bern, Bern, Switzerland
| | - Jacobijn Gussekloo
- Department of Internal Medicine, Section of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, the Netherlands.,Department of Public Health and Primary Care, Leiden University Medical Center, Leiden, the Netherlands
| | - Stella Trompet
- Department of Internal Medicine, Section of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, the Netherlands
| | | |
Collapse
|
10
|
Tang X, Song ZH, Wang D, Yang J, Augusto Cardoso M, Zhou JB, Simó R. Spectrum of thyroid dysfunction and dementia: a dose-response meta-analysis of 344,248 individuals from cohort studies. Endocr Connect 2021; 10:410-421. [PMID: 33875615 PMCID: PMC8111311 DOI: 10.1530/ec-21-0047] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 03/19/2021] [Indexed: 12/21/2022]
Abstract
Thyroid hormone, as a modifiable risk factor for dementia, promotes neurocognitive function and regulates metabolic processes. Various studies have defined different thyroid-stimulating hormone cutoffs, but the safest thyroid-stimulating hormone concentration was absent. A dose-response meta-analysis describing the overall functional relation and identifying exposure intervals associated with a higher or lower disease risk is thus desirable. Therefore, our current analysis was conducted to understand the influence of thyroid dysfunction on dementia risk. We searched PubMed, Embase, and Web of Science before May 1, 2020 for human studies published in English. Studies were considered for inclusion if they used a cohort study design to measure the risk of dementia in different thyroid function status groups, diagnosed thyroid functional status and all-cause dementia, included participants aged >18 years, and provided quantitative measures of data. The analysis contained 17 articles with 344,248 individuals with a 7.8-year mean follow-up. Ten studies with 329,287 participants indicated that only subclinical hyperthyroidism was associated with an increased risk of dementia. In contrast, subclinical hypothyroidism, clinical hyperthyroidism, and clinical hypothyroidism did not affect dementia. In the dose-response meta-analysis with 46,417 samples from 11 studies, the association of thyroid-stimulating hormone with the risk of dementia exhibited a U-shaped curve. Our study indicated that subclinical hyperthyroidism was associated with the risk of dementia and the thyroid-stimulating hormone concentration at around 1.55-1.60 mU/L as the optimum range for the risk of dementia.
Collapse
Affiliation(s)
- Xingyao Tang
- Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Zhi-Hui Song
- Department of Pharmacy, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Dawei Wang
- General Practice Department, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Jinkui Yang
- Department of Endocrinology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Marly Augusto Cardoso
- Department of Nutrition, School of Public Health, University of Sao Paulo, Sao Paulo, Brazil
| | - Jian-Bo Zhou
- Department of Endocrinology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Correspondence should be addressed to J-B Zhou:
| | - Rafael Simó
- Endocrinology and Nutrition Department, Hospital Universitari Vall d’Hebron, Diabetes and Metabolism Research Unit, Vall d’Hebron Institut de Recerca (VHIR), Universitat Autònoma de Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| |
Collapse
|
11
|
Anstey KJ, Ee N, Eramudugolla R, Jagger C, Peters R. A Systematic Review of Meta-Analyses that Evaluate Risk Factors for Dementia to Evaluate the Quantity, Quality, and Global Representativeness of Evidence. J Alzheimers Dis 2020; 70:S165-S186. [PMID: 31306123 PMCID: PMC6700718 DOI: 10.3233/jad-190181] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Background: The translation of evidence on dementia risk factors into clinical advice requires careful evaluation of the methodology and scope of data from which risk estimates are obtained. Objective: To evaluate the quantity, quality, and representativeness of evidence, we conducted a review of reviews of risk factors for Alzheimer’s disease (AD), Vascular dementia (VaD), and Any Dementia. Methods: PubMed, Cochrane library, and the Global Index Medicus were searched to identify meta-analyses of observational studies of risk factors for AD, VaD, and Any Dementia. PROSPERO CRD42017053920. Results: Meta-analysis data were available for 34 risk factors for AD, 26 risk factors for Any Dementia and eight for VaD. Quality of evidence varied greatly in terms of the number of contributing studies, whether data on midlife exposure was available, and consistency of measures. The most evidence was available for cardiovascular risk factors. The most geographically representative evidence (five of six global regions) was available for alcohol, physical activity, diabetes, high midlife BMI, antihypertensives, and motor function. Evidence from Australia/Oceana or Africa was limited. With the exception of diabetes, meta-analysis data were unavailable from Latin America/Caribbean. Midlife specific data were only available for cholesterol and arthritis. Conclusion: There is a lack of midlife specific data, limited data on VaD, and a lack of geographical representation for many risk factors for dementia. The quality, quantity, and representativeness of evidence needs to be considered before recommendations are made about the relevance of risk factors in mid- or late-life or for dementia subtypes.
Collapse
Affiliation(s)
- Kaarin J Anstey
- School of Psychology, University of New South Wales, Sydney, NSW, Australia.,Neuroscience Research Australia (NeuRA), Sydney, NSW, Australia
| | - Nicole Ee
- School of Psychology, University of New South Wales, Sydney, NSW, Australia.,Neuroscience Research Australia (NeuRA), Sydney, NSW, Australia
| | | | - Carol Jagger
- Newcastle Institute for Ageing, Newcastle University, Newcastle, UK
| | - Ruth Peters
- School of Psychology, University of New South Wales, Sydney, NSW, Australia.,Neuroscience Research Australia (NeuRA), Sydney, NSW, Australia
| |
Collapse
|
12
|
Joy Mathew C, Jose MT, Elshaikh AO, Shah L, Lee R, Cancarevic I. Is Hyperthyroidism a Possible Etiology of Early Onset Dementia? Cureus 2020; 12:e10603. [PMID: 33133806 PMCID: PMC7586400 DOI: 10.7759/cureus.10603] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Dementia, a disabling syndrome of the elderly characterized by the decline in memory and cognition, is increasing in incidence and affects not only the individual but also their family and close ones. Hyperthyroidism can mimic many other diseases and untreated hyperthyroidism can lead to adverse problems of various systems including the heart, bones, muscles, menstrual cycle, and fertility. In this article, we have tried to evaluate the association between hyperthyroidism and dementia, as well as the impact of hyperthyroidism management in the treatment and prevention of dementia. Studies available in the PubMed database have been used, excluding animal studies and including studies of adults above the age of 50. The analysis of studies reveals that thyroid dysfunction can lead to cognitive impairment. It has not been able to prove that hyperthyroidism can lead to an earlier onset of dementia. But subclinical hyperthyroidism, thyroid-stimulating hormone (TSH) levels below the normal range, and high free thyroxine (T4) levels increase the risk of dementia among the elderly. The possible mechanisms involved in this association have also been discussed. Thus, we concluded that it is essential to detect and manage hyperthyroidism at an earlier stage since hyperthyroidism increases the risk of dementia. The possibility of using antithyroid treatment in euthyroid dementia is yet to be studied extensively.
Collapse
Affiliation(s)
| | - Merin Tresa Jose
- Family Medicine, California Institute of Behavioral Neurosciences & Psychology, Fairfield, USA
| | - Abeer O Elshaikh
- Internal Medicine, California Institute of Behavioral Neurosciences & Psychology, Fairfield, USA
| | - Lisa Shah
- Family and Community Medicine, Smt. Nathiba Hargovandas Lakhmichand Municipal Medical College, Ahmedabad, IND
| | - Robert Lee
- Surgery, California Institute of Behavioral Neurosciences & Psychology, Fairfield, USA
| | - Ivan Cancarevic
- Internal Medicine, California Institute of Behavioral Neurosciences & Psychology, Fairfield, USA
| |
Collapse
|
13
|
Bavarsad K, Hosseini M, Hadjzadeh MAR, Sahebkar A. The effects of thyroid hormones on memory impairment and Alzheimer's disease. J Cell Physiol 2019; 234:14633-14640. [PMID: 30680727 DOI: 10.1002/jcp.28198] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 01/16/2019] [Indexed: 01/24/2023]
Abstract
Thyroid hormones (THs) have a wide and important range of effects within the central nervous system beginning from fetal life and continuing throughout the adult life. Thyroid disorders are one of the major causes of cognitive impairment including Alzheimer's disease (AD). Several studies in recent years have indicated an association between hypothyroidism or hyperthyroidism and AD. Despite available evidence for this association, it remains unclear whether thyroid dysfunction results from or contributes to the progression of AD. This review discusses the role of THs in learning and memory and summarizes the studies that have linked thyroid function and AD. Eventually, we elaborate how THs may be effective in treating AD by putting forward potential mechanisms.
Collapse
Affiliation(s)
- Kowsar Bavarsad
- Department of Physiology, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mahmoud Hosseini
- Department of Physiology, Mashhad University of Medical Sciences, Mashhad, Iran.,Division of Neurocognitive Sciences, Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mousa-Al-Reza Hadjzadeh
- Department of Physiology, Mashhad University of Medical Sciences, Mashhad, Iran.,Division of Neurocognitive Sciences, Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Amirhossein Sahebkar
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Medical Biotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| |
Collapse
|
14
|
Jonklaas J, Razvi S. Reference intervals in the diagnosis of thyroid dysfunction: treating patients not numbers. Lancet Diabetes Endocrinol 2019; 7:473-483. [PMID: 30797750 DOI: 10.1016/s2213-8587(18)30371-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 12/05/2018] [Accepted: 12/12/2018] [Indexed: 12/20/2022]
Abstract
Although assigning a diagnosis of thyroid dysfunction appears quite simple, this is often not the case. Issues that make it unclear whether thyroid function is normal include transient changes in thyroid parameters, inter-individual and intra-individual differences in thyroid parameters, age-related differences, and ethnic variations. In addition, a statistically calculated distribution of thyroid analytes does not necessarily coincide with intervals or cutoffs that have predictive value for beneficial or adverse health outcomes. Based on current clincial trial data, it is unclear which individuals with mild thyroid-stimulating hormone elevations will benefit from levothyroxine treatment. For example, only a small number of patients with thyroid-stimulating hormone values of more than 10 mIU/L have been studied in a randomised manner. Even if therapy is initiated for abnormal thyroid function, not all treated individuals are maintained at the desired treatment target, and therefore might still be at risk. The consequence of this is that each patient's thyroid function needs to be assessed on an individual basis with the entire clinical picture in mind. Monitoring also needs to be vigilant, and the targets for treatment reassessed continually.
Collapse
Affiliation(s)
| | - Salman Razvi
- Department of Endocrinology, University of Newcastle, Newcastle, UK
| |
Collapse
|
15
|
Wändell P, Carlsson AC, Sundquist J, Sundquist K. Effect of Levothyroxine Treatment on Incident Dementia in Adults with Atrial Fibrillation and Hypothyroidism. Clin Drug Investig 2019; 39:187-195. [PMID: 30552650 PMCID: PMC6394624 DOI: 10.1007/s40261-018-0740-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Background and Objective The possible adverse or positive effects of levothyroxine treatment among patients with atrial fibrillation have been debated. Atrial fibrillation, levothyroxine treatment, and dementia are common among older adults, yet little is known about the effects of levothyroxine on the development of dementia. Methods The study population included all adults (n = 12,057) aged ≥ 45 years with a diagnosis of atrial fibrillation at 75 primary care centers in Sweden during 2001–2007 without an earlier recorded dementia diagnosis. Patients with a diagnosis of hypothyroidism and levothyroxine prescription (n = 756; 180 men and 576 women), or with a prescription without this diagnosis (n = 415, 100 men and 315 women), were compared to patients without a diagnosis and prescription (n = 10,886). Cox regression was performed, with hazard ratios and 95% confidence intervals, with outcome defined as dementia of all causes until 31 December, 2010. Results During a mean 5.7 years (standard deviation 2.4 years) of follow-up, a total of 749 patients with atrial fibrillation (6.2%) were diagnosed with dementia. Women with hypothyroidism and a levothyroxine prescription showed lower hazard ratios (0.61; 0.41–0.90) in adjusted Cox regression models (age, socioeconomic factors, co-morbidity, and warfarin treatment). Levothyroxine prescription without hypothyroidism was non-significant. Conclusions We found that women with atrial fibrillation with levothyroxine treatment and hypothyroidism have a lower risk of incident dementia than women with atrial fibrillation without levothyroxine treatment and no hypothyroidism. The results should be confirmed in larger studies. Electronic supplementary material The online version of this article (10.1007/s40261-018-0740-3) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Per Wändell
- Division of Family Medicine and Primary Care, Department of Neurobiology, Care Sciences and Society, Karolinska Institute, Alfred Nobels Allé 23, 141 83, Huddinge, Sweden.
| | - Axel C Carlsson
- Division of Family Medicine and Primary Care, Department of Neurobiology, Care Sciences and Society, Karolinska Institute, Alfred Nobels Allé 23, 141 83, Huddinge, Sweden
| | - Jan Sundquist
- Center for Primary Health Care Research, Lund University, Malmö, Sweden
- Department of Family Medicine and Community Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Center for Community-based Healthcare Research and Education (CoHRE), Department of Functional Pathology, School of Medicine, Shimane University, Matsue, Shimane, Japan
| | - Kristina Sundquist
- Center for Primary Health Care Research, Lund University, Malmö, Sweden
- Department of Family Medicine and Community Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Center for Community-based Healthcare Research and Education (CoHRE), Department of Functional Pathology, School of Medicine, Shimane University, Matsue, Shimane, Japan
| |
Collapse
|
16
|
TDP-43 proteinopathy in aging: Associations with risk-associated gene variants and with brain parenchymal thyroid hormone levels. Neurobiol Dis 2019; 125:67-76. [PMID: 30682540 DOI: 10.1016/j.nbd.2019.01.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 01/13/2019] [Accepted: 01/19/2019] [Indexed: 02/08/2023] Open
Abstract
TDP-43 proteinopathy is very prevalent among the elderly (affecting at least 25% of individuals over 85 years of age) and is associated with substantial cognitive impairment. Risk factors implicated in age-related TDP-43 proteinopathy include commonly inherited gene variants, comorbid Alzheimer's disease pathology, and thyroid hormone dysfunction. To test parameters that are associated with aging-related TDP-43 pathology, we performed exploratory analyses of pathologic, genetic, and biochemical data derived from research volunteers in the University of Kentucky Alzheimer's Disease Center autopsy cohort (n = 136 subjects). Digital pathologic methods were used to discriminate and quantify both neuritic and intracytoplasmic TDP-43 pathology in the hippocampal formation. Overall, 46.4% of the cases were positive for TDP-43 intracellular inclusions, which is consistent with results in other prior community-based cohorts. The pathologies were correlated with hippocampal sclerosis of aging (HS-Aging) linked genotypes. We also assayed brain parenchymal thyroid hormone (triiodothyronine [T3] and thyroxine [T4]) levels. In cases with SLCO1A2/IAPP or ABCC9 risk associated genotypes, the T3/T4 ratio tended to be reduced (p = .051 using 2-tailed statistical test), and in cases with low T3/T4 ratios (bottom quintile), there was a higher likelihood of HS-Aging pathology (p = .025 using 2-tailed statistical test). This is intriguing because the SLCO1A2/IAPP and ABCC9 risk associated genotypes have been associated with altered expression of the astrocytic thyroid hormone receptor (protein product of the nearby gene SLCO1C1). These data indicate that dysregulation of thyroid hormone signaling may play a role in age-related TDP-43 proteinopathy.
Collapse
|
17
|
Bavarsad K, Hadjzadeh MAR, Hosseini M, Pakdel R, Beheshti F, Bafadam S, Ashaari Z. Effects of levothyroxine on learning and memory deficits in a rat model of Alzheimer’s disease: the role of BDNF and oxidative stress. Drug Chem Toxicol 2018; 43:57-63. [DOI: 10.1080/01480545.2018.1481085] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Kowsar Bavarsad
- Student Research Committee, Department of Physiology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Physiology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mousa-Al-Reza Hadjzadeh
- Division of Neurocognitive Sciences, Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mahmoud Hosseini
- Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Roghayeh Pakdel
- Research Center of Physiology, Semnan University of Medical Sciences, Semnan, Iran
| | - Farimah Beheshti
- Department of Basic Sciences and Neuroscience Research Center, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran
| | - Soleyman Bafadam
- Department of Physiology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Zeinab Ashaari
- Department of Physiology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| |
Collapse
|
18
|
Brenowitz WD, Han F, Kukull WA, Nelson PT. Treated hypothyroidism is associated with cerebrovascular disease but not Alzheimer's disease pathology in older adults. Neurobiol Aging 2018; 62:64-71. [PMID: 29107848 PMCID: PMC5743774 DOI: 10.1016/j.neurobiolaging.2017.10.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 10/02/2017] [Accepted: 10/02/2017] [Indexed: 01/01/2023]
Abstract
Thyroid hormone disease is common among older adults and is associated with cognitive impairment. However, pathologic correlates are not well understood. We studied pathologic and clinical factors associated with hypothyroidism, the most common manifestation of thyroid disease, in research subjects seen annually for clinical evaluations at U.S. Alzheimer's Disease Centers. Thyroid disease and treatment status were assessed during clinician interviews. Among autopsied subjects, there were 555 participants with treated hypothyroidism and 2146 without known thyroid disease; hypothyroidism was associated with severe atherosclerosis (odds ratio: 1.35; 95% confidence interval: 1.02, 1.79) but not Alzheimer's disease pathologies (amyloid plaques or neurofibrillary tangles). Among participants who did not undergo autopsy (4598 with treated hypothyroidism and 20,945 without known thyroid hormone disease), hypercholesterolemia and cerebrovascular disease (stroke and/or transient ischemic attack) were associated with hypothyroidism, complementing findings in the smaller autopsy sample. This is the first large-scale evaluation of neuropathologic concomitants of hypothyroidism in aged individuals. Clinical hypothyroidism was prevalent (>20% of individuals studied) and was associated with cerebrovascular disease but not Alzheimer's disease-type neuropathology.
Collapse
Affiliation(s)
- Willa D Brenowitz
- National Alzheimer's Coordinating Center (NACC), Department of Epidemiology, University of Washington, Seattle, WA, USA.
| | - Fang Han
- Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, China
| | - Walter A Kukull
- National Alzheimer's Coordinating Center (NACC), Department of Epidemiology, University of Washington, Seattle, WA, USA
| | - Peter T Nelson
- Division of Neuropathology, Department of Pathology, University of Kentucky, Lexington, KY, USA; Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA.
| |
Collapse
|
19
|
Thyroid hormones in extreme longevity. Mech Ageing Dev 2017; 165:98-106. [PMID: 28286215 DOI: 10.1016/j.mad.2017.03.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 02/27/2017] [Accepted: 03/08/2017] [Indexed: 11/20/2022]
Abstract
The aim of the present review was to summarize knowledge about thyroid hormones (THs) and longevity. Longevity is a complex multifactorial phenomenon on which specific biological pathways, including hormonal networks involved in the regulation of homeostasis and survival, exert a strong impact. THs are the key responsible for growth, metabolism rate and energy expenditure, and help in maintaining cognition, bone and cardiovascular health. THs production and metabolism are fine tuned, and may help the organism to cope with a variety of environmental challenges. Experimental evidence suggests that hypothyroid state may favor longevity by reducing metabolism rate, oxidative stress and cell senescence. Data from human studies involving healthy subjects and centenarians seem to confirm this view, but THs changes observed in older patients affected by chronic diseases cannot be always interpreted as a protective adaptive mechanism aimed at reducing catabolism and prolonging survival. Medications, selected chronic diseases and multi-morbidity can interfere with thyroid function, and their impact is still to be elucidated.
Collapse
|