The optimal healthy ranges of thyroid function defined by the risk of cardiovascular disease and mortality: systematic review and individual participant data meta-analysis.

BACKGROUND: Reference intervals of thyroid-stimulating hormone (TSH) and free thyroxine (FT4) are statistically defined by the 2·5-97·5th percentiles, without accounting for potential risk of clinical outcomes. We aimed to define the optimal healthy ranges of TSH and FT4 based on the risk of cardiovascular disease and mortality. METHODS: This systematic review and individual participant data (IPD) meta-analysis identified eligible prospective cohorts through the Thyroid Studies Collaboration, supplemented with a systematic search via Embase, MEDLINE (Ovid), Web of science, the Cochrane Central Register of Controlled Trials, and Google Scholar from Jan 1, 2011, to Feb 12, 2017 with an updated search to Oct 13, 2022 (cohorts found in the second search were not included in the IPD). We included cohorts that collected TSH or FT4, and cardiovascular outcomes or mortality for adults (aged ≥18 years). We excluded cohorts that included solely pregnant women, individuals with overt thyroid diseases, and individuals with cardiovascular disease. We contacted the study investigators of eligible cohorts to provide IPD on demographics, TSH, FT4, thyroid peroxidase antibodies, history of cardiovascular disease and risk factors, medication use, cardiovascular disease events, cardiovascular disease mortality, and all-cause mortality. The primary outcome was a composite outcome including cardiovascular disease events (coronary heart disease, stroke, and heart failure) and all-cause mortality. Secondary outcomes were the separate assessment of cardiovascular disease events, all-cause mortality, and cardiovascular disease mortality. We performed one-step (cohort-stratified Cox models) and two-step (random-effects models) meta-analyses adjusting for age, sex, smoking, systolic blood pressure, diabetes, and total cholesterol. The study was registered with PROSPERO, CRD42017057576. FINDINGS: We identified 3935 studies, of which 53 cohorts fulfilled the inclusion criteria and 26 cohorts agreed to participate. We included IPD on 134 346 participants with a median age of 59 years (range 18-106) at baseline. There was a J-shaped association of FT4 with the composite outcome and secondary outcomes, with the 20th (median 13·5 pmol/L [IQR 11·2-13·9]) to 40th percentiles (median 14·8 pmol/L [12·3-15·0]) conveying the lowest risk. Compared with the 20-40th percentiles, the age-adjusted and sex-adjusted hazard ratio (HR) for FT4 in the 80-100th percentiles was 1·20 (95% CI 1·11-1·31) for the composite outcome, 1·34 (1·20-1·49) for all-cause mortality, 1·57 (1·31-1·89) for cardiovascular disease mortality, and 1·22 (1·11-1·33) for cardiovascular disease events. In individuals aged 70 years and older, the 10-year absolute risk of composite outcome increased over 5% for women with FT4 greater than the 85th percentile (median 17·6 pmol/L [IQR 15·0-18·3]), and men with FT4 greater than the 75th percentile (16·7 pmol/L [14·0-17·4]). Non-linear associations were identified for TSH, with the 60th (median 1·90 mIU/L [IQR 1·68-2·25]) to 80th percentiles (2·90 mIU/L [2·41-3·32]) associated with the lowest risk of cardiovascular disease and mortality. Compared with the 60-80th percentiles, the age-adjusted and sex-adjusted HR of TSH in the 0-20th percentiles was 1·07 (95% CI 1·02-1·12) for the composite outcome, 1·09 (1·05-1·14) for all-cause mortality, and 1·07 (0·99-1·16) for cardiovascular disease mortality. INTERPRETATION: There was a J-shaped association of FT4 with cardiovascular disease and mortality. Low concentrations of TSH were associated with a higher risk of all-cause mortality and cardiovascular disease mortality. The 20-40th percentiles of FT4 and the 60-80th percentiles of TSH could represent the optimal healthy ranges of thyroid function based on the risk of cardiovascular disease and mortality, with more than 5% increase of 10-year composite risk identified for FT4 greater than the 85th percentile in women and men older than 70 years. We propose a feasible approach to establish the optimal healthy ranges of thyroid function, allowing for better identification of individuals with a higher risk of thyroid-related outcomes. FUNDING: None.

Association of habitual coffee consumption and kidney function: A prospective analysis in the Rotterdam Study.

BACKGROUND & AIMS: Population-based studies have suggested a protective effect of coffee against development of chronic kidney disease (CKD), possibly through coffee's anti-inflammatory and antioxidant compounds. Studies on coffee and kidney function decline in the general population are scarce. We studied associations of habitual coffee consumption with repeated assessments of estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio (ACR). METHODS: We used data from 7,914 participants of the population-based Rotterdam Study. Baseline coffee consumption data (cups/day) were obtained from home interviews and validated food frequency questionnaires (1997-2008). Repeated assessments of eGFR (ml/min per 1.73 m2, 1997-2014) were calculated according to the creatinine-based CKD Epidemiology Collaboration equation of 2012. Repeated assessments of urinary albumin and creatinine were used to estimate ACR (mg/g, 2006-2014). Data were analyzed by applying linear mixed models, adjusted for sociodemographic, lifestyle and dietary factors, and cardiovascular disease risk factors. Predefined subgroup analyses were performed stratified by CKD risk factors. RESULTS: Participants' mean (SD) baseline age was 66 (10) years, 57% were women and median [IQR] coffee consumption was 3.0 [2.0, 5.0] cups/day. Those drinking more coffee were more likely to smoke, and to have type 2 diabetes (T2D) and obesity. Mean eGFR was 79 (15) ml/min per 1.73 m2. In the total study population, coffee was not associated with longitudinal eGFR during a median of 5.4 years of follow-up (ß = 0.04 ml/min per 1.73 m2 per one cup/day [95% CI: -0.10,0.18]). However, among those aged >70 years, one additional coffee cup/day was associated with on average 0.84 (0.51,1.18) ml/min per 1.73 m2 higher longitudinal eGFR. Among obese participants this estimate was 0.32 (0.01,0.63). A protective trend was also observed among former smokers (0.17 [-0.03,0.39]) and those with T2D (0.42 [-0.05,0.88]). Coffee was not associated with longitudinal ACR (0.01 mg/ml [-0.01,0.02]). CONCLUSION: While coffee was not associated with eGFR and ACR in the total population, more coffee consumption was associated with higher longitudinal eGFR among those at higher risk for CKD, i.e., among those aged 70+ and obese participants. These findings require confirmation in other prospective cohort studies.

Sorafenib-Induced Changes in Thyroid Hormone Levels in Patients Treated for Hepatocellular Carcinoma.

Context: The pathogenesis of tyrosine kinase inhibitor-induced thyroid hormone (TH) alterations are still a matter of debate. Objective: The objective of this study was to determine the effects of sorafenib on TH levels in patients with hepatocellular carcinoma (HCC) and to evaluate possible mechanisms. Design: We performed a prospective cohort study between 2009 and 2016. Setting: This study was conducted at a tertiary referral center. Patients: This study included 57 consecutive patients with HCC who were treated with sorafenib. Main Outcome Measure: Thyroid-stimulating hormone (TSH) and free thyroxine (FT4) levels were measured every 6 weeks, and extensive thyroid function tests (TFTs) were measured before treatment (t0), after 6 weeks (t6), and at the end of therapy. The effect of sorafenib on TH transport by monocarboxylate transporter (MCT)8 or MCT10 was tested in transfected COS1 cells. Results: Four patients (7%) developed thyroiditis. Among the other patients, 30% had elevation of TSH or FT4 above the normal range. Overall, between t0 and t6, mean TSH increased from 1.28 to 1.57 mU/L (P < 0.001) and mean FT4 from 18.4 to 21.2 pmol/L (P < 0.001). Simultaneously, the serum triiodothyronine (T3)/reverse triiodothyronine ratio and the (T3/thyroxine) ×100 ratio decreased. Sorafenib decreased cellular T3 uptake by MCT8 and to a lesser extent by MCT10. Conclusions: These in vivo data suggest that sorafenib affects TFTs on multiple levels. Our in vitro experiments suggest a possible role of sorafenib-induced inhibition of T3 transport into the cell by MCT8 and MCT10.