Circulating testosterone is usually reduced in men with cirrhosis, but there has not been a comprehensive analysis of androgen status or circulating oestrogens. Little is known about associations between circulating sex steroids with aspects of health in this population.We report data from men with cirrhosis and low serum testosterone (<12 nmol/L or calculated free testosterone <230 pmol/L). Comprehensive circulating sex steroid profiles were measured by liquid chromatography-mass spectrometry and compared with age-matched controls. Relationships between sex hormone levels, severity of liver disease, biochemistry and clinical outcomes were assessed.Serum oestrone and oestradiol were significantly elevated in men with cirrhosis compared with controls (median, 869.1 pmol/L vs. 133.8 pmol/L and 166.7 pmol/L vs. 84.6 pmol/L respectively). Serum oestrone correlated with MELD score (correlation +0.306, P < 0.001) and inversely correlated with serum sodium (correlation -0.208, P = 0.004) and haemoglobin (correlation -0.177, P = 0.012). No such correlations were observed for oestradiol. Serum testosterone levels inversely correlated with MELD score (correlation -0.294, P < 0.001) and positively with handgrip strength (correlation +0.242, P < 0.001), physical activity (correlation +0.276, P = 0.012), haemoglobin (correlation +0.282, P < 0.001) and serum sodium (+0.344, P < 0.001). Dihydrotestosterone inversely correlated with MELD score (correlation -0.225, P = 0.002) and shared similar significant relationships to testosterone.Low serum androgens and elevated serum oestrone (but not oestradiol) are associated with higher MELD and individual adverse health outcomes in cirrhotic cohort of men selected for low testosterone. Serum oestrone may be a novel marker of ill health in this population. Whether low androgens are markers or mediators of ill health requires further investigation.
TSH-receptor autoantibodies (TRAbs) are a valuable diagnostic tool for comfirming a diagnosis of Graves’ disease (GD). While there is evidence that high TRAb levels are associated with relapse of GD, whether a discrimination of TRAb into stimulating (TSAb) and blocking (TBAb) autoantibodies would benefit the clinician in terms of outcome prediction remains unclear. To address this issue, we have determined TRAb, TSAb and TBAb levels in serum samples of ninety-six euthyroid patients with GD taken four weeks after antithyroid drug withdrawal (ATDT). Forty-seven patients (49 %) underwent relapse of GD within two years. Amongst those, forty-one (87 %) had been positive for TRAb and thirty-five (74 %) for TSAb after treatment. All patients except one were negative for TBAb. The correlation between TRAb and TSAb in those treated GD patients was relatively weak (r = 0.268, p < 0.001). Based on a cut-off limit of 1.5 IU/l, the positive and negative predictive values with respect to prediction of relapse were too low for any clinical relevance (TRAb: 49 % and 54 %; TSAb: 51 % and 55 %). However, when a cut-off level above 10 IU/l was used, the positive and negative predictive values increased to 83 % and 62 %. The additional measurement of TSAb or TBAb in those samples after therapy did not add additional information, even at higher deciscion thresholds. In conclusion, differentiation of TRAb into TSAb and TBAb is of no help in the prediction of relapse of GD in euthyroid patients at the end of ATDT, and only high TRAb levels are associated with relapse.
To examine the prevalence and prognostic implications of low serum testosterone levels in men with chronic liver disease.We conducted an observational study at a tertiary referral centre.Baseline serum testosterone was measured in 171 men presenting to the Victorian Liver Transplant Unit for liver transplant evaluation. Patients were followed up to liver transplant or death.Sixty-one per cent of men had a low total testosterone level (TT, <10 nm), and 90% of men had a low calculated free testosterone level (cFT, <230 pm). During the available observation time (median 8 months, interquartile range 4-14 months), 56 men (33%) died and 63 (37%) received a liver transplant. Fifty-two (30%) survived without a transplant. Median time to death was 8 months (range 2-13) and to liver transplant was 8 months (4-14). Baseline low TT and cFT levels both (P < 0·0001) predicted mortality. Moreover, in a Cox proportional hazard model, both low total (P = 0·02) and free testosterone (P = 0·007) levels remained predictive of death independently of established prognostic factors, such as the model for end-stage liver disease (MELD) score and serum sodium levels. A decrease in TT by 1 nm and in cFT by 10 pm was associated with an 8% increase in mortality.Low testosterone levels are common in men with severe liver disease and predict mortality independent of MELD, the standard score used to prioritize the allocation of liver transplants.
Several influences modulate biochemical responses to a weight-adjusted levothyroxine (l-T4) replacement dose. We conducted a secondary analysis of the relationship of l-T4 dose to TSH and free T3 (FT3), using a prospective observational study examining the interacting equilibria between thyroid parameters. We studied 353 patients on steady-state l-T4 replacement for autoimmune thyroiditis or after surgery for malignant or benign thyroid disease. Peripheral deiodinase activity was calculated as a measure of T4-T3 conversion efficiency. In euthyroid subjects, the median l-T4 dose was 1.3 μg/kg per day (interquartile range (IQR) 0.94,1.60). The dose was independently associated with gender, age, aetiology and deiodinase activity (all P<0.001). Comparable FT3 levels required higher l-T4 doses in the carcinoma group (n=143), even after adjusting for different TSH levels. Euthyroid athyreotic thyroid carcinoma patients (n=50) received 1.57 μg/kg per day l-T4 (IQR 1.40, 1.69), compared to 1.19 μg/kg per day (0.85,1.47) in autoimmune thyroiditis (P<0.01, n=76) and 1.08 μg/kg per day (0.82, 1.44) in patients operated on for benign disease (P< 0.01, n=80). Stratifying patients by deiodinase activity categories of <23, 23-29 and >29 nmol/s revealed an increasing FT3-FT4 dissociation; the poorest converters showed the lowest FT3 levels in spite of the highest dose and circulating FT4 (P<0.001). An l-T4-related FT3-TSH disjoint was also apparent; some patients with fully suppressed TSH failed to raise FT3 above the median level. These findings imply that thyroid hormone conversion efficiency is an important modulator of the biochemical response to l-T4; FT3 measurement may be an additional treatment target; and l-T4 dose escalation may have limited success to raise FT3 appropriately in some cases.
Low circulating testosterone levels have been associated with increased mortality in men. We hypothesized that the prognostic role of testosterone in men with type 2 diabetes mellitus (T2DM) is influenced by its carrier protein sex hormone-binding globulin (SHBG).We conducted a prospective cohort study at a tertiary referral centre.In total, 531 men with T2DM presenting to a diabetes clinic in 2004-2005 were followed prospectively until death, or July 31, 2014, and a survival analysis was performed. The main outcome measure was all cause mortality.Over a mean (S.D.) follow up of 7.6 years (2.6) 175 men (33%) died. In Cox proportional hazard models both higher SHBG (Hazard Ratio (HR) 1.012 (95% CI 1.002-1.022), P=0.02) and lower calculated free testosterone (cFT) (HR 0.995 (95% CI 0.993-0.998), P=0.001) were risk factors for all cause mortality independently of age, BMI, presence of macro- and microvascular disease, duration of T2DM, hemoglobin, renal function, insulin use, C-reactive protein and homeostatic model of insulin resistance. By contrast, the inverse association of total testosterone (TT) with mortality weakened after these adjustments (P=0.11). SHBG remained associated with mortality (P<0.001) both if substituted for or added to TT in the multivariable model. In the fully adjusted model, an increase of SHBG by 17.3 nmol/l (1 S.D.) increased mortality by 22% and a decrease in cFT by 81 pmol/l (1 S.D.) increased mortality by 45%.The association of SHBG with mortality in men with T2DM is novel. Whether SHBG acts via regulation of testosterone, has intrinsic biological roles, or is a marker of poor health requires further study.
The objective of the study was to evaluate the roles of central and peripheral T3 regulation. In a prospective study involving 1 796 patients, the equilibria between FT3 and TSH were compared in untreated and L-T4-treated patients with varying functional states, residual thyroid secretory capacities and magnitudes of TSH stimulation. T3 concentrations were stable over wide variations in TSH levels (from 0.2 to 7 mU/l) and endogenous T4 production in untreated patients, but unbalanced in L-T4-treated athyreotic patients where T3 correlated with exogenous T4 supply. T3 stability was related to TSH-stimulated deiodinase activity by clinical observation, as predicted by theoretical modelling. Deiodinase activity in treated patients was reduced due to both diminished responsiveness to TSH and lack of thyroidal capacity. Deiodinase activity was increased in high thyroid volume, compared to lower volumes in euthyroid patients (<5 ml, p<0.001). While deiodinase differed between euthyroid and subclinically hypothyroid patients in high volume, 26.7 nmol/s (23.6, 29.2), n=214 vs. 28.9 nmol/s (26.7, 31.5), n=20, p=0.02, it was equivalent between the 2 functional groups in low volume, 23.3 nmol/s (21.3, 26.1), n=117 vs. 24.6 nmol/s (22.2, 27.5), n=38, p=0.22. These findings suggest that the thyroid gland and peripheral tissues are integrated in the physiological process of T3 homeostasis in humans via a feed-forward TSH motif, which coordinates peripheral and central regulatory mechanisms. Regulatory and capacity deficiencies collectively impair T3 homeostasis in L-T4-treated patients.