Low glomerular filtration rate values are associated with higher TSH in an elderly population at high cardiovascular disease risk.

Background: Hypothyroidism is associated with impaired glomerular filtration rate (GFR), a recognized cardiovascular disease (CVD), and mortality risk factor. In older adults, this association remains unexplored. We aimed to determine the relationship of elevated TSH with GFR in an elderly population at high CVD risk. Methods: Older adults (age>65ys) with high CVD risk defined by two or more CVD risk factors: smoking (S), high blood pressure (HBP), high total cholesterol, low HDL cholesterol, diabetes (DM), metabolic syndrome or previous cardiovascular event, were prospectively included at our ambulatory Endocrine Clinic. Patients under levothyroxine or thyroid disease were excluded. TSH> 6mU/l defined subclinical hypothyroidism (ScH) with normal free T4 levels. Estimated GFR was calculated by the Berlin-Initiative Study (BIS)-1 formula for elderly population. Urinary albumin to creatinine ratio (uACR), IL-6 and TNF-α, and Carotid intima-media thickness (CIMT) were also determined. The U Mann-Whitney test, the Spearman test, and multiple linear regression were used as statistical tests. Results: Finally 246 patients (68% females) were included and 20 (8%) had ScH. This group, was older (median, Q1-Q3: 77,72-78; 72,68-77 years, p=0.01) and DM was less frequent than in the euthyroid group (35 vs 58%, p=0.039). Lower fasting glucose (-20%,p=0.01), GFR (-14%,p=0.01) and freeT4 (-10%,p<0.001) were found compared to euthyroid patients. A higher prevalence of Kidney failure was found in ScH (80 vs. 46%, p=0.003) vs. euthyroid individuals. Significant correlations with GFR were detected: age (r-0.482,p<0.001), TSH (r-0.172,p=0.004), IL-6 (r-0.150,p=0.047), TNF-α (r-0.274,p<0.001), uACR (r-0.170,p=0.009) and CIMT(r-0.189,p=0.004). By multiple linear regression, in a model adjusted by age, sex, BMI, uACR, S, DM, TNF-α and HBP, TSH (Bst -0.14, p=0.023, R2 = 0.25) was found an independent predictor of GFR. Conclusion: In older adults with high CVD risk, ScH is associated with lower renal function, and this relationship is present regardless of other cardiometabolic risk factors. These results suggest that ScH could contribute to low GFR and excess CVD risk, although this hypothesis should be addressed in longitudinal studies.

Association between worse metabolic control and increased thyroid volume and nodular disease in elderly adults with metabolic syndrome.

BACKGROUND: Metabolic syndrome has been associated with nodular goiter. Our aim was to evaluate which metabolic parameters in elderly patients with metabolic syndrome are associated with thyroid enlargement or increased prevalence of thyroid nodules. METHODS: In this cross-sectional study, 77 patients >65 years of age with metabolic syndrome were included. We evaluated the presence of thyroid nodules and thyroid volume by ultrasonography and several biochemical, metabolic and anthropometric parameters. Only patients with thyrotropin (thyroid-stimulating hormone, TSH) levels between 0.3 and 6 mU/L were included. We further divided subjects into two groups-type 2 diabetes mellitus (T2DM) and non-T2DM and established comparisons between them. RESULTS: Among all parameters analyzed we found a significant correlation between glycated hemoglobin (HbA1c) and volume (r=0.261, P=0.027) or number of nodules (r=0.266, P=0.023). Neither sex, age, body mass index (BMI), metformin, nor levothyroxine use were associated with thyroid volume or nodularity. Within the whole cohort, those patients with T2DM had larger thyroid volumes compared to non-T2DM [median (confidence interval, CI) 6.976 (5.220-10.789) vs. 5.034 (3.796-6.034) mL, P<0.008). Furthermore, a larger proportion of T2DM patients presented thyroid volumes >5.8 mL [69 vs. 23%, P<0.001; odds ratio=7.25 (CI 2.04-25.56)]. CONCLUSIONS: In elderly patients with metabolic syndrome, worse metabolic control, represented by higher HbA1c levels, was found associated to increased prevalence of thyroid nodules and larger thyroid volume. Moreover, within the whole metabolic syndrome group, patients with T2DM had the largest thyroid volumes.

High TSH and low T4 as prognostic markers in older patients.

OBJECTIVE: To examine the association between thyroid profile and morbidity/mortality (MM) in hospitalized older patients. DESIGN: This is a retrospective study of patients over the age of 60 yr admitted to the Dr. Cesar Milstein Hospital between 2009 and 2010 and who had thyroid function tests (TFT). The patients were grouped as per their thyroid tests and their clinical characteristics and MM was associated with their TFT. High MM was defined as mortality, intensive care unit (ICU) requirement or prolonged hospital stay (>18 days, 75th percentile), and mortality assessed during an 18-month follow-up period after their hospital discharge. RESULTS: Out of 2599 older patients admitted to our hospital, 7% had TFT performed for various reasons. The patients who had TFT were mostly women and presented in a more serious clinical condition compared to the rest of the patients. The patients were grouped as per their thyroid values as follows: 61% of them had a non-thyroidal illness, 25% were euthyroid,7% had overt hyperthyroidism, 5% overt hypothyroidism and 1% had subclinical hyper- or hypothyroidism. The hypothyroid patients had a worse clinical outcome compared to the others. Patients with increased MM exhibited higher TSH and lower TT4 (p<0.005). Short-term MM (OR=2.0,95%CI=1.1-3.6, p<0.01) was associated with the decrease of TT4 adjusted by age, sex, T3 and TSH, while for long-term MM the increase in TSH (OR=1.6,95%CI 1.1-2.3, p<0.05) was also significant. CONCLUSION: Among hospitalized older patients who had TFT tests, low TT4 and high TSH were associated with a worse prognosis. We propose that TFT be used as an additional tool in assessing MM in elderly hospitalized patients.