@article {890, title = {Thyroid status, cardiovascular risk, and mortality in older adults.}, journal = {JAMA}, volume = {295}, year = {2006}, month = {2006 Mar 01}, pages = {1033-41}, abstract = {

CONTEXT: Previous studies have suggested that subclinical abnormalities in thyroid-stimulating hormone levels are associated with detrimental effects on the cardiovascular system.

OBJECTIVE: To determine the relationship between baseline thyroid status and incident atrial fibrillation, incident cardiovascular disease, and mortality in older men and women not taking thyroid medication.

DESIGN, SETTING, AND PARTICIPANTS: A total of 3233 US community-dwelling individuals aged 65 years or older with baseline serum thyroid-stimulating hormone levels were enrolled in 1989-1990 in the Cardiovascular Health Study, a large, prospective cohort study.

MAIN OUTCOME MEASURES: Incident atrial fibrillation, coronary heart disease, cerebrovascular disease, cardiovascular death, and all-cause death assessed through June 2002. Analyses are reported for 4 groups defined according to thyroid function test results: subclinical hyperthyroidism, euthyroidism, subclinical hypothyroidism, and overt hypothyroidism.

RESULTS: Individuals with overt thyrotoxicosis (n = 4) were excluded because of small numbers. Eighty-two percent of participants (n = 2639) had normal thyroid function, 15\% (n = 496) had subclinical hypothyroidism, 1.6\% (n = 51) had overt hypothyroidism, and 1.5\% (n = 47) had subclinical hyperthyroidism. After exclusion of those with prevalent atrial fibrillation, individuals with subclinical hyperthyroidism had a greater incidence of atrial fibrillation compared with those with normal thyroid function (67 events vs 31 events per 1000 person-years; adjusted hazard ratio, 1.98; 95\% confidence interval, 1.29-3.03). No differences were seen between the subclinical hyperthyroidism group and euthyroidism group for incident coronary heart disease, cerebrovascular disease, cardiovascular death, or all-cause death. Likewise, there were no differences between the subclinical hypothyroidism or overt hypothyroidism groups and the euthyroidism group for cardiovascular outcomes or mortality. Specifically, individuals with subclinical hypothyroidism had an adjusted hazard ratio of 1.07 (95\% confidence interval, 0.90-1.28) for incident coronary heart disease.

CONCLUSION: Our data show an association between subclinical hyperthyroidism and development of atrial fibrillation but do not support the hypothesis that unrecognized subclinical hyperthyroidism or subclinical hypothyroidism is associated with other cardiovascular disorders or mortality.

}, keywords = {Aged, Atrial Fibrillation, Cardiovascular Diseases, Female, Humans, Hyperthyroidism, Hypothyroidism, Male, Proportional Hazards Models, Risk Factors, Thyroid Gland, Thyrotropin}, issn = {1538-3598}, doi = {10.1001/jama.295.9.1033}, author = {Cappola, Anne R and Fried, Linda P and Arnold, Alice M and Danese, Mark D and Kuller, Lewis H and Burke, Gregory L and Tracy, Russell P and Ladenson, Paul W} } @article {1053, title = {Subclinical thyroid dysfunction, cardiac function, and the risk of heart failure. The Cardiovascular Health study.}, journal = {J Am Coll Cardiol}, volume = {52}, year = {2008}, month = {2008 Sep 30}, pages = {1152-9}, abstract = {

OBJECTIVES: The goal of this study was to determine whether subclinical thyroid dysfunction was associated with incident heart failure (HF) and echocardiogram abnormalities.

BACKGROUND: Subclinical hypothyroidism and hyperthyroidism have been associated with cardiac dysfunction. However, long-term data on the risk of HF are limited.

METHODS: We studied 3,044 adults>or=65 years of age who initially were free of HF in the Cardiovascular Health Study. We compared adjudicated HF events over a mean 12-year follow-up and changes in cardiac function over the course of 5 years among euthyroid participants, those with subclinical hypothyroidism (subdivided by thyroid-stimulating hormone [TSH] levels: 4.5 to 9.9, >or=10.0 mU/l), and those with subclinical hyperthyroidism.

RESULTS: Over the course of 12 years, 736 participants developed HF events. Participants with TSH>or=10.0 mU/l had a greater incidence of HF compared with euthyroid participants (41.7 vs. 22.9 per 1,000 person years, p=0.01; adjusted hazard ratio: 1.88; 95\% confidence interval: 1.05 to 3.34). Baseline peak E velocity, which is an echocardiographic measurement of diastolic function associated with incident HF in the CHS cohort, was greater in those patients with TSH>or=10.0 mU/l compared with euthyroid participants (0.80 m/s vs. 0.72 m/s, p=0.002). Over the course of 5 years, left ventricular mass increased among those with TSH>or=10.0 mU/l, but other echocardiographic measurements were unchanged. Those patients with TSH 4.5 to 9.9 mU/l or with subclinical hyperthyroidism had no increase in risk of HF.

CONCLUSIONS: Compared with euthyroid older adults, those adults with TSH>or=10.0 mU/l have a moderately increased risk of HF and alterations in cardiac function but not older adults with TSH<10.0 mU/l. Clinical trials should assess whether the risk of HF might be ameliorated by thyroxine replacement in individuals with TSH>or=10.0 mU/l.

}, keywords = {Aged, Aged, 80 and over, Cohort Studies, Echocardiography, Female, Heart, Heart Failure, Heart Function Tests, Humans, Hyperthyroidism, Hypertrophy, Left Ventricular, Hypothyroidism, Male, Risk Factors, Time Factors}, issn = {1558-3597}, doi = {10.1016/j.jacc.2008.07.009}, author = {Rodondi, Nicolas and Bauer, Douglas C and Cappola, Anne R and Cornuz, Jacques and Robbins, John and Fried, Linda P and Ladenson, Paul W and Vittinghoff, Eric and Gottdiener, John S and Newman, Anne B} } @article {1246, title = {Subclinical thyroid dysfunction and incident hip fracture in older adults.}, journal = {Arch Intern Med}, volume = {170}, year = {2010}, month = {2010 Nov 22}, pages = {1876-83}, abstract = {

BACKGROUND: Subclinical thyroid dysfunction is common in older adults and affects bone metabolism, but its effects on fracture risk have not been reported. We sought to determine prospectively whether older men and women with subclinical hyperthyroidism or hypothyroidism have an increased risk of hip fracture.

METHODS: Prospective cohort of 3567 US community-dwelling adults, 65 years or older, with biochemically defined subclinical thyroid dysfunction or euthyroidism was enrolled from June 10, 1989, through May 30, 1990, and followed up through 2004. Main outcome measures included incidence and hazard ratios (HRs), with 95\% confidence intervals (CIs), of confirmed incident hip fractures for groups with subclinical hypothyroidism, subclinical hyperthyroidism, and euthyroidism as defined at baseline.

RESULTS: During 39 952 person-years (median follow-up, 13 years), hip fracture incidence (per 1000 men-years) was 13.65 in men with subclinical hyperthyroidism (n = 29) and 10.27 in men with subclinical hypothyroidism (n = 184), both greater than 5.0 in men with euthyroidism (n = 1159). Men with subclinical hypothyroidism had a multivariable-adjusted HR of 2.31 (95\% CI, 1.25-4.27); those with subclinical hyperthyroidism, 3.27 (0.99-11.30). After excluding those with baseline use of thyroid-altering medications, men with endogenous subclinical hyperthyroidism had a higher HR of 4.91 (95\% CI, 1.13-21.27), as did men with endogenous subclinical hypothyroidism (2.45, 1.27-4.73). Hip fracture incidence (per 1000 women-years) was 8.93 in women with subclinical hypothyroidism (n = 359) and 10.90 in women with subclinical hyperthyroidism (n = 142) compared with 10.18 in women with euthyroidism (n = 1694). No clear association between subclinical dysfunction and fracture was observed in women.

CONCLUSIONS: Older men with subclinical hyperthyroidism or hypothyroidism are at increased risk for hip fracture. Whether treatment of the subclinical syndrome reduces this risk is unknown.

}, keywords = {Aged, Female, Follow-Up Studies, Hip Fractures, Humans, Hyperthyroidism, Hypothyroidism, Incidence, Male, Multivariate Analysis, Proportional Hazards Models, Prospective Studies, Risk Factors, Sex Distribution, Thyrotropin, United States}, issn = {1538-3679}, doi = {10.1001/archinternmed.2010.424}, author = {Lee, Jennifer S and B{\r u}zkov{\'a}, Petra and Fink, Howard A and Vu, Joseph and Carbone, Laura and Chen, Zhao and Cauley, Jane and Bauer, Doug C and Cappola, Anne R and Robbins, John} } @article {1545, title = {Subclinical hyperthyroidism and the risk of coronary heart disease and mortality.}, journal = {Arch Intern Med}, volume = {172}, year = {2012}, month = {2012 May 28}, pages = {799-809}, abstract = {

BACKGROUND: Data from prospective cohort studies regarding the association between subclinical hyperthyroidism and cardiovascular outcomes are conflicting.We aimed to assess the risks of total and coronary heart disease (CHD) mortality, CHD events, and atrial fibrillation (AF) associated with endogenous subclinical hyperthyroidism among all available large prospective cohorts.

METHODS: Individual data on 52 674 participants were pooled from 10 cohorts. Coronary heart disease events were analyzed in 22 437 participants from 6 cohorts with available data, and incident AF was analyzed in 8711 participants from 5 cohorts. Euthyroidism was defined as thyrotropin level between 0.45 and 4.49 mIU/L and endogenous subclinical hyperthyroidism as thyrotropin level lower than 0.45 mIU/L with normal free thyroxine levels, after excluding those receiving thyroid-altering medications.

RESULTS: Of 52 674 participants, 2188 (4.2\%) had subclinical hyperthyroidism. During follow-up, 8527 participants died (including 1896 from CHD), 3653 of 22 437 had CHD events, and 785 of 8711 developed AF. In age- and sex-adjusted analyses, subclinical hyperthyroidism was associated with increased total mortality (hazard ratio[HR], 1.24, 95\% CI, 1.06-1.46), CHD mortality (HR,1.29; 95\% CI, 1.02-1.62), CHD events (HR, 1.21; 95\%CI, 0.99-1.46), and AF (HR, 1.68; 95\% CI, 1.16-2.43).Risks did not differ significantly by age, sex, or preexisting cardiovascular disease and were similar after further adjustment for cardiovascular risk factors, with attributable risk of 14.5\% for total mortality to 41.5\% forAF in those with subclinical hyperthyroidism. Risks for CHD mortality and AF (but not other outcomes) were higher for thyrotropin level lower than 0.10 mIU/L compared with thyrotropin level between 0.10 and 0.44 mIU/L(for both, P value for trend, .03).

CONCLUSION: Endogenous subclinical hyperthyroidism is associated with increased risks of total, CHD mortality, and incident AF, with highest risks of CHD mortality and AF when thyrotropin level is lower than 0.10 mIU/L.

}, keywords = {Adolescent, Adult, Age Distribution, Aged, Aged, 80 and over, Atrial Fibrillation, Cause of Death, Cohort Studies, Coronary Artery Disease, Female, Humans, Hyperthyroidism, Male, Middle Aged, Prognosis, Prospective Studies, Risk Assessment, Severity of Illness Index, Sex Distribution, Survival Analysis, Switzerland, Thyroid Function Tests, Thyrotropin, Young Adult}, issn = {1538-3679}, doi = {10.1001/archinternmed.2012.402}, author = {Collet, Tinh-Hai and Gussekloo, Jacobijn and Bauer, Douglas C and den Elzen, Wendy P J and Cappola, Anne R and Balmer, Philippe and Iervasi, Giorgio and Asvold, Bj{\o}rn O and Sgarbi, Jos{\'e} A and V{\"o}lzke, Henry and Gencer, Bari{\c s} and Maciel, Rui M B and Molinaro, Sabrina and Bremner, Alexandra and Luben, Robert N and Maisonneuve, Patrick and Cornuz, Jacques and Newman, Anne B and Khaw, Kay-Tee and Westendorp, Rudi G J and Franklyn, Jayne A and Vittinghoff, Eric and Walsh, John P and Rodondi, Nicolas} } @article {5877, title = {A meta-analysis of thyroid-related traits reveals novel loci and gender-specific differences in the regulation of thyroid function.}, journal = {PLoS Genet}, volume = {9}, year = {2013}, month = {2013}, pages = {e1003266}, abstract = {

Thyroid hormone is essential for normal metabolism and development, and overt abnormalities in thyroid function lead to common endocrine disorders affecting approximately 10\% of individuals over their life span. In addition, even mild alterations in thyroid function are associated with weight changes, atrial fibrillation, osteoporosis, and psychiatric disorders. To identify novel variants underlying thyroid function, we performed a large meta-analysis of genome-wide association studies for serum levels of the highly heritable thyroid function markers TSH and FT4, in up to 26,420 and 17,520 euthyroid subjects, respectively. Here we report 26 independent associations, including several novel loci for TSH (PDE10A, VEGFA, IGFBP5, NFIA, SOX9, PRDM11, FGF7, INSR, ABO, MIR1179, NRG1, MBIP, ITPK1, SASH1, GLIS3) and FT4 (LHX3, FOXE1, AADAT, NETO1/FBXO15, LPCAT2/CAPNS2). Notably, only limited overlap was detected between TSH and FT4 associated signals, in spite of the feedback regulation of their circulating levels by the hypothalamic-pituitary-thyroid axis. Five of the reported loci (PDE8B, PDE10A, MAF/LOC440389, NETO1/FBXO15, and LPCAT2/CAPNS2) show strong gender-specific differences, which offer clues for the known sexual dimorphism in thyroid function and related pathologies. Importantly, the TSH-associated loci contribute not only to variation within the normal range, but also to TSH values outside the reference range, suggesting that they may be involved in thyroid dysfunction. Overall, our findings explain, respectively, 5.64\% and 2.30\% of total TSH and FT4 trait variance, and they improve the current knowledge of the regulation of hypothalamic-pituitary-thyroid axis function and the consequences of genetic variation for hypo- or hyperthyroidism.

}, keywords = {Female, Genome-Wide Association Study, Humans, Hyperthyroidism, Hypothyroidism, Male, Phenotype, Polymorphism, Genetic, Polymorphism, Single Nucleotide, Sex Characteristics, Signal Transduction, Thyroid Gland, Thyrotropin, Thyroxine}, issn = {1553-7404}, doi = {10.1371/journal.pgen.1003266}, author = {Porcu, Eleonora and Medici, Marco and Pistis, Giorgio and Volpato, Claudia B and Wilson, Scott G and Cappola, Anne R and Bos, Steffan D and Deelen, Joris and den Heijer, Martin and Freathy, Rachel M and Lahti, Jari and Liu, Chunyu and Lopez, Lorna M and Nolte, Ilja M and O{\textquoteright}Connell, Jeffrey R and Tanaka, Toshiko and Trompet, Stella and Arnold, Alice and Bandinelli, Stefania and Beekman, Marian and B{\"o}hringer, Stefan and Brown, Suzanne J and Buckley, Brendan M and Camaschella, Clara and de Craen, Anton J M and Davies, Gail and de Visser, Marieke C H and Ford, Ian and Forsen, Tom and Frayling, Timothy M and Fugazzola, Laura and G{\"o}gele, Martin and Hattersley, Andrew T and Hermus, Ad R and Hofman, Albert and Houwing-Duistermaat, Jeanine J and Jensen, Richard A and Kajantie, Eero and Kloppenburg, Margreet and Lim, Ee M and Masciullo, Corrado and Mariotti, Stefano and Minelli, Cosetta and Mitchell, Braxton D and Nagaraja, Ramaiah and Netea-Maier, Romana T and Palotie, Aarno and Persani, Luca and Piras, Maria G and Psaty, Bruce M and R{\"a}ikk{\"o}nen, Katri and Richards, J Brent and Rivadeneira, Fernando and Sala, Cinzia and Sabra, Mona M and Sattar, Naveed and Shields, Beverley M and Soranzo, Nicole and Starr, John M and Stott, David J and Sweep, Fred C G J and Usala, Gianluca and van der Klauw, Melanie M and van Heemst, Diana and van Mullem, Alies and Vermeulen, Sita H and Visser, W Edward and Walsh, John P and Westendorp, Rudi G J and Widen, Elisabeth and Zhai, Guangju and Cucca, Francesco and Deary, Ian J and Eriksson, Johan G and Ferrucci, Luigi and Fox, Caroline S and Jukema, J Wouter and Kiemeney, Lambertus A and Pramstaller, Peter P and Schlessinger, David and Shuldiner, Alan R and Slagboom, Eline P and Uitterlinden, Andr{\'e} G and Vaidya, Bijay and Visser, Theo J and Wolffenbuttel, Bruce H R and Meulenbelt, Ingrid and Rotter, Jerome I and Spector, Tim D and Hicks, Andrew A and Toniolo, Daniela and Sanna, Serena and Peeters, Robin P and Naitza, Silvia} } @article {6795, title = {Subclinical thyroid dysfunction and fracture risk: a meta-analysis.}, journal = {JAMA}, volume = {313}, year = {2015}, month = {2015 May 26}, pages = {2055-65}, abstract = {

IMPORTANCE: Associations between subclinical thyroid dysfunction and fractures are unclear and clinical trials are lacking.

OBJECTIVE: To assess the association of subclinical thyroid dysfunction with hip, nonspine, spine, or any fractures.

DATA SOURCES AND STUDY SELECTION: The databases of MEDLINE and EMBASE (inception to March 26, 2015) were searched without language restrictions for prospective cohort studies with thyroid function data and subsequent fractures.

DATA EXTRACTION: Individual participant data were obtained from 13 prospective cohorts in the United States, Europe, Australia, and Japan. Levels of thyroid function were defined as euthyroidism (thyroid-stimulating hormone [TSH], 0.45-4.49 mIU/L), subclinical hyperthyroidism (TSH <0.45 mIU/L), and subclinical hypothyroidism (TSH >=4.50-19.99 mIU/L) with normal thyroxine concentrations.

MAIN OUTCOME AND MEASURES: The primary outcome was hip fracture. Any fractures, nonspine fractures, and clinical spine fractures were secondary outcomes.

RESULTS: Among 70,298 participants, 4092 (5.8\%) had subclinical hypothyroidism and 2219 (3.2\%) had subclinical hyperthyroidism. During 762,401 person-years of follow-up, hip fracture occurred in 2975 participants (4.6\%; 12 studies), any fracture in 2528 participants (9.0\%; 8 studies), nonspine fracture in 2018 participants (8.4\%; 8 studies), and spine fracture in 296 participants (1.3\%; 6 studies). In age- and sex-adjusted analyses, the hazard ratio (HR) for subclinical hyperthyroidism vs euthyroidism was 1.36 for hip fracture (95\% CI, 1.13-1.64; 146 events in 2082 participants vs 2534 in 56,471); for any fracture, HR was 1.28 (95\% CI, 1.06-1.53; 121 events in 888 participants vs 2203 in 25,901); for nonspine fracture, HR was 1.16 (95\% CI, 0.95-1.41; 107 events in 946 participants vs 1745 in 21,722); and for spine fracture, HR was 1.51 (95\% CI, 0.93-2.45; 17 events in 732 participants vs 255 in 20,328). Lower TSH was associated with higher fracture rates: for TSH of less than 0.10 mIU/L, HR was 1.61 for hip fracture (95\% CI, 1.21-2.15; 47 events in 510 participants); for any fracture, HR was 1.98 (95\% CI, 1.41-2.78; 44 events in 212 participants); for nonspine fracture, HR was 1.61 (95\% CI, 0.96-2.71; 32 events in 185 participants); and for spine fracture, HR was 3.57 (95\% CI, 1.88-6.78; 8 events in 162 participants). Risks were similar after adjustment for other fracture risk factors. Endogenous subclinical hyperthyroidism (excluding thyroid medication users) was associated with HRs of 1.52 (95\% CI, 1.19-1.93) for hip fracture, 1.42 (95\% CI, 1.16-1.74) for any fracture, and 1.74 (95\% CI, 1.01-2.99) for spine fracture. No association was found between subclinical hypothyroidism and fracture risk.

CONCLUSIONS AND RELEVANCE: Subclinical hyperthyroidism was associated with an increased risk of hip and other fractures, particularly among those with TSH levels of less than 0.10 mIU/L and those with endogenous subclinical hyperthyroidism. Further study is needed to determine whether treating subclinical hyperthyroidism can prevent fractures.

}, keywords = {Adolescent, Adult, Aged, Aged, 80 and over, Female, Fractures, Bone, Hip Fractures, Humans, Hyperthyroidism, Hypothyroidism, Male, Middle Aged, Risk Factors, Spinal Fractures, Thyrotropin, Young Adult}, issn = {1538-3598}, doi = {10.1001/jama.2015.5161}, author = {Blum, Manuel R and Bauer, Douglas C and Collet, Tinh-Hai and Fink, Howard A and Cappola, Anne R and da Costa, Bruno R and Wirth, Christina D and Peeters, Robin P and Asvold, Bj{\o}rn O and den Elzen, Wendy P J and Luben, Robert N and Imaizumi, Misa and Bremner, Alexandra P and Gogakos, Apostolos and Eastell, Richard and Kearney, Patricia M and Strotmeyer, Elsa S and Wallace, Erin R and Hoff, Mari and Ceresini, Graziano and Rivadeneira, Fernando and Uitterlinden, Andr{\'e} G and Stott, David J and Westendorp, Rudi G J and Khaw, Kay-Tee and Langhammer, Arnuf and Ferrucci, Luigi and Gussekloo, Jacobijn and Williams, Graham R and Walsh, John P and J{\"u}ni, Peter and Aujesky, Drahomir and Rodondi, Nicolas} } @article {7585, title = {Association between subclinical thyroid dysfunction and change in bone mineral density in prospective cohorts.}, journal = {J Intern Med}, volume = {283}, year = {2018}, month = {2018 Jan}, pages = {56-72}, abstract = {

BACKGROUND: Subclinical hyperthyroidism (SHyper) has been associated with increased risk of hip and other fractures, but the linking mechanisms remain unclear.

OBJECTIVE: To investigate the association between subclinical thyroid dysfunction and bone loss.

METHODS: Individual participant data analysis was performed after a systematic literature search in MEDLINE/EMBASE (1946-2016). Two reviewers independently screened and selected prospective cohorts providing baseline thyroid status and serial bone mineral density (BMD) measurements. We classified thyroid status as euthyroidism (thyroid-stimulating hormone [TSH] 0.45-4.49 mIU/L), SHyper (TSH < 0.45 mIU/L) and subclinical hypothyroidism (SHypo, TSH >= 4.50-19.99 mIU/L) both with normal free thyroxine levels. Our primary outcome was annualized percentage BMD change (\%ΔBMD) from serial dual X-ray absorptiometry scans of the femoral neck, total hip and lumbar spine, obtained from multivariable regression in a random-effects two-step approach.

RESULTS: Amongst 5458 individuals (median age 72 years, 49.1\% women) from six prospective cohorts, 451 (8.3\%) had SHypo and 284 (5.2\%) had SHyper. During 36 569 person-years of follow-up, those with SHyper had a greater annual bone loss at the femoral neck versus euthyroidism: \%ΔBMD = -0.18 (95\% CI: -0.34, -0.02; I2 = 0\%), with a nonstatistically significant pattern at the total hip: \%ΔBMD = -0.14 (95\% CI: -0.38, 0.10; I2 = 53\%), but not at the lumbar spine: \%ΔBMD = 0.03 (95\% CI: -0.30, 0.36; I2 = 25\%); especially participants with TSH < 0.10 mIU/L showed an increased bone loss in the femoral neck (\%Δ BMD = -0.59; [95\% CI: -0.99, -0.19]) and total hip region (\%ΔBMD = -0.46 [95\% CI: -1.05, -0.13]). In contrast, SHypo was not associated with bone loss at any site.

CONCLUSION: Amongst adults, SHyper was associated with increased femoral neck bone loss, potentially contributing to the increased fracture risk.

}, keywords = {Aged, Asymptomatic Diseases, Bone Density, Female, Fractures, Bone, Humans, Hyperthyroidism, Hypothyroidism, Male, Risk Factors}, issn = {1365-2796}, doi = {10.1111/joim.12688}, author = {Segna, D and Bauer, D C and Feller, M and Schneider, C and Fink, H A and Aubert, C E and Collet, T-H and da Costa, B R and Fischer, K and Peeters, R P and Cappola, A R and Blum, M R and van Dorland, H A and Robbins, J and Naylor, K and Eastell, R and Uitterlinden, A G and Rivadeneira Ramirez, F and Gogakos, A and Gussekloo, J and Williams, G R and Schwartz, A and Cauley, J A and Aujesky, D A and Bischoff-Ferrari, H A and Rodondi, N} }