for the Thyroid Studies Collaboration C ONTROVERSY PERSISTS ON THEindications for screening and threshold levels of thyroidstimulating hormone (TSH) for treatment of subclinical hypothyroidism, 1-3 defined as elevated serum TSH levels with normal thyroxine (T 4 ) concentrations. Because subclinical hypothyroidism has been associated with hypercholesterolemia 4 and atherosclerosis, 5 screening and treatment have been advocated to prevent cardiovascular disease. 3 However, data on the associations with coronary heart disease (CHD) events and mortality are conflicting among several large prospective cohorts. [6][7][8][9] Three recent study-level metaanalyses 10-12 found modestly increased risks for CHD and mortality, but with heterogeneity among individual studies that used different TSH cutoffs, dif-See also Patient Page. CME available online at www.jamaarchivescme.com and questions on p 1392.

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% for AF 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.

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Objectives To investigate the performance of classic risk factors, and of some new biomarkers, in predicting cardiovascular mortality in very old people from the general population with no history of cardiovascular disease. Design The Leiden 85-plus Study (1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004) is an observational prospective cohort study with 5 years of follow-up. Setting General population of the city of Leiden, the Netherlands. Participants Population based sample of participants aged 85 years (215 women and 87 men) with no history of cardiovascular disease; no other exclusion criteria. Main measurements Cause specific mortality was registered during follow-up. All classic risk factors included in the Framingham risk score (sex, systolic blood pressure, total and high density lipoprotein cholesterol, diabetes mellitus, smoking and electrocardiogram based left ventricular hypertrophy), as well as plasma concentrations of the new biomarkers homocysteine, folic acid, C reactive protein, and interleukin 6, were assessed at baseline. Results During follow-up, 108 of the 302 participants died; 32% (35/108) of deaths were from cardiovascular causes. Classic risk factors did not predict cardiovascular mortality when used in the Framingham risk score (area under receiver operating characteristic curve 0.53, 95% confidence interval 0.42 to 0.63) or in a newly calibrated model (0.53, 0.43 to 0.64). Of the new biomarkers studied, homocysteine had most predictive power (0.65, 0.55 to 0.75). Entering any additional risk factor or combination of factors into the homocysteine prediction model did not increase its discriminative power. Conclusions In very old people from the general population with no history of cardiovascular disease, concentrations of homocysteine alone can accurately identify those at high risk of cardiovascular mortality, whereas classic risk factors included in the Framingham risk score do not. These preliminary findings warrant validation in a separate cohort.

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 Blum et al.

Background ACC/AHA Guidelines for the Diagnosis and Management of Heart Failure (HF) recommend investigating exacerbating conditions, such as thyroid dysfunction, but without specifying impact of different TSH levels. Limited prospective data exist regarding the association between subclinical thyroid dysfunction and HF events. Methods and Results We performed a pooled analysis of individual participant data using all available prospective cohorts with thyroid function tests and subsequent follow-up of HF events. Individual data on 25,390 participants with 216,248 person-years of follow-up were supplied from 6 prospective cohorts in the United States and Europe. Euthyroidism was defined as TSH 0.45–4.49 mIU/L, subclinical hypothyroidism as TSH 4.5–19.9 mIU/L and subclinical hyperthyroidism as TSH <0.45 mIU/L, both with normal free thyroxine levels. Among 25,390 participants, 2068 had subclinical hypothyroidism (8.1%) and 648 subclinical hyperthyroidism (2.6%). In age- and gender-adjusted analyses, risks of HF events were increased with both higher and lower TSH levels (P for quadratic pattern <0.01): hazard ratio (HR) was 1.01 (95% confidence interval [CI] 0.81–1.26) for TSH 4.5–6.9 mIU/L, 1.65 (CI 0.84–3.23) for TSH 7.0–9.9 mIU/L, 1.86 (CI 1.27–2.72) for TSH 10.0–19.9 mIUL/L (P for trend <0.01), and was 1.31 (CI 0.88–1.95) for TSH 0.10–0.44 mIU/L and 1.94 (CI 1.01–3.72) for TSH <0.10 mIU/L (P for trend = 0.047). Risks remained similar after adjustment for cardiovascular risk factors. Conclusions Risks of HF events were increased with both higher and lower TSH levels, particularly for TSH ≥10 mIU/L and for TSH <0.10 mIU/L.

IntroductionIn 2008, the Ministry of Health, Welfare and Sport commissioned the National Care for the Elderly Programme. While numerous research projects in older persons’ health care were to be conducted under this national agenda, the Programme further advocated the development of The Older Persons and Informal Caregivers Survey Minimum DataSet (TOPICS-MDS) which would be integrated into all funded research protocols. In this context, we describe TOPICS data sharing initiative (www.topics-mds.eu).Materials and MethodsA working group drafted TOPICS-MDS prototype, which was subsequently approved by a multidisciplinary panel. Using instruments validated for older populations, information was collected on demographics, morbidity, quality of life, functional limitations, mental health, social functioning and health service utilisation. For informal caregivers, information was collected on demographics, hours of informal care and quality of life (including subjective care-related burden).ResultsBetween 2010 and 2013, a total of 41 research projects contributed data to TOPICS-MDS, resulting in preliminary data available for 32,310 older persons and 3,940 informal caregivers. The majority of studies sampled were from primary care settings and inclusion criteria differed across studies.DiscussionTOPICS-MDS is a public data repository which contains essential data to better understand health challenges experienced by older persons and informal caregivers. Such findings are relevant for countries where increasing health-related expenditure has necessitated the evaluation of contemporary health care delivery. Although open sharing of data can be difficult to achieve in practice, proactively addressing issues of data protection, conflicting data analysis requests and funding limitations during TOPICS-MDS developmental phase has fostered a data sharing culture. To date, TOPICS-MDS has been successfully incorporated into 41 research projects, thus supporting the feasibility of constructing a large (>30,000 observations), standardised dataset pooled from various study protocols with different sampling frameworks. This unique implementation strategy improves efficiency and facilitates individual-level data meta-analysis.

Background Atrial fibrillation (AF) is a highly prevalent disorder leading to heart failure, stroke, and death. Enhanced understanding of modifiable risk factors may yield opportunities for prevention. The risk of AF is increased in subclinical hyperthyroidism, but it is uncertain whether variations in thyroid function within the normal range or subclinical hypothyroidism are also associated with AF. Methods We conducted a systematic review and obtained individual participant data from prospective cohort studies that measured thyroid function at baseline and assessed incident AF. Studies were identified from MEDLINE and EMBASE databases from inception to July 27, 2016. The euthyroid state was defined as thyroid stimulating hormone (TSH) 0.45–4.49mIU/l, and subclinical hypothyroidism as TSH 4.5–19.9mIU/l with free thyroxine (fT4) levels within reference range. The association of TSH levels in the euthyroid and subclinical hypothyroid range with incident AF was examined using Cox proportional hazards models. In euthyroid participants, we additionally examined the association between fT4 levels and incident AF. Results Of 30,085 participants from 11 cohorts (278,955 person-years of follow-up), 1,958 (6.5%) had subclinical hypothyroidism, and 2,574 individuals (8.6%) developed AF during follow-up. TSH at baseline was not significantly associated with incident AF in euthyroid participants or those with subclinical hypothyroidism. Higher fT4 levels at baseline in euthyroid individuals were associated with increased AF risk in age- and sex-adjusted analyses (hazard ratio=1.45; 95% confidence interval, 1.26–1.66, for the highest quartile vs the lowest quartile of fT4, p for trend ≤0.001 across quartiles). Estimates did not substantially differ after further adjustment for preexisting cardiovascular disease. Conclusion In euthyroid individuals, higher circulating fT4 levels, but not TSH levels, are associated with increased risk of incident AF.