Standardising the biochemical confirmation of adult male hypogonadism; a joint position statement by the Society for Endocrinology and Association of Clinical Biochemistry and Laboratory Medicine.

Background: Inter-assay variation between different immunoassays and different mass spectrometry methods hampers the biochemical confirmation of male hypogonadism. Furthermore, some laboratories utilis eassay manufacturer reference ranges that do not necessarily mirror assay performance characteristics, with the lower limit of normality ranging from 4.9 nmol/L to 11 nmol/L. The quality of the normative data underlying commercial immunoassay reference ranges is uncertain.Design: A working group reviewed published evidence and agreed upon standardised reporting guidance to augment total testosterone reports. Results: Evidence-based guidance on appropriate blood sampling, clinical action limits, and other major factors likely to affect the interpretation of results are provided. Conclusions: This article aims to improve the quality of the interpretation of testosterone results by non-specialist clinicians. It also discusses approaches for assay harmonisation which have been successful in some but not all healthcare systems.

Standardising the biochemical confirmation of adult male hypogonadism: A joint position statement by the Society for Endocrinology and Association of Clinical Biochemistry and Laboratory Medicine.

BACKGROUND: Inter-assay variation between different immunoassays and different mass spectrometry methods hampers the biochemical confirmation of male hypogonadism. Furthermore, some laboratories utilise assay manufacturer reference ranges that do not necessarily mirror assay performance characteristics, with the lower limit of normality ranging from 4.9 nmol/L to 11 nmol/L. The quality of the normative data underlying commercial immunoassay reference ranges is uncertain. DESIGN: A working group reviewed published evidence and agreed upon standardised reporting guidance to augment total testosterone reports. RESULTS: Evidence-based guidance on appropriate blood sampling, clinical action limits, and other major factors likely to affect the interpretation of results are provided. CONCLUSIONS: This article aims to improve the quality of the interpretation of testosterone results by non-specialist clinicians. It also discusses approaches for assay harmonisation which have been successful in some but not all healthcare systems.

Lessons learnt from the variation across 6741 family/general practices in England in the use of treatments for hypogonadism.

INTRODUCTION: We have previously reported rates of diagnosis of male hypogonadism in United Kingdom (UK) general practices. We aimed to identify factors associated with testosterone prescribing in UK general practice. METHODS: We determined for 6741 general practices in England, the level of testosterone prescribing in men and the relation between volume of testosterone prescribing and (1) demographic characteristics of the practice, (2) % patients with specific comorbidities and (3) national GP patient survey results. RESULTS: The largest volume (by prescribing volume) agents were injectable preparations at a total cost in the 12-month period 2018/19 of £8,172,519 with gel preparations in second place: total cost £4,795,057. Transdermal patches, once the only alternative to testosterone injections or implants, were little prescribed: total cost £222,022. The analysis accounted for 0.27 of the variance in testosterone prescribing between general practices. Thus, most of this variance was not accounted for by the analysis. There was a strong univariant relation (r = .95, P < .001) between PDE5-I prescribing and testosterone prescribing. Other multivariant factors independently linked with more testosterone prescribing were as follows: HIGHER proportion of men with type 2 diabetes(T2DM) on target control (HbA1c ≤ 58 mmol/mol) and HIGHER overall practice rating on the National Patient Survey for good experience, while non-white ethnicity and socio-economic deprivation were associated with less testosterone prescribing. There were a number of comorbidity factors associated with less prescribing of testosterone (such as T2DM, hypertension and stroke/TIA). CONCLUSION: Our analysis has indicated that variation between general practices in testosterone prescribing in a well developed health economy is only related to small degree (r2  = 0.27) to factors that we can define. This suggests that variation in amount of testosterone prescribed is largely related to general practitioner choice/other factors not studied and may be amenable to measures to increase knowledge/awareness of male hypogonadism, with implications for men's health.

Significant increase in high-density lipoprotein cholesterol with fibrates is associated with low pretreatment high-density lipoprotein cholesterol: findings from an outpatient clinic setting.

BACKGROUND: Change in high-density lipoprotein cholesterol (HDL-C) observed in large randomized controlled trials using fibrates has varied. Inconsistent cardiovascular outcomes have also been the common theme of these trials. Subgroup analysis of even the negative trials, however, reveals significant reduction in cardiovascular disease in patients with low HDL-C and high triglycerides. We wished to study HDL-C change following fibrate therapy in our lipid clinic and determine the factors associated with HDL-C change. METHODS: Data were collected from case notes of patients started on fibrates (n=248) between 2002 and 2008 in the lipid clinics at Heart of England NHS Foundation Trust. Regression analyses were carried out to determine factors associated with changes in HDL-C. RESULTS: Linear regression analysis revealed that HDL-C change was associated with pretreatment HDL-C (P<0.001), diabetes (P=0.004) and treatment duration (P=0.036). Multiple regression analysis with all of the factors in the model suggested that they were independent. Patients with a baseline HDL-C <1.0 mmol/L showed a greater HDL-C increase when compared to patients with a baseline HDL-C ≥1.0 mmol/L; HDL-C <1.0 mmol/L (increase of 0.15 mmol/L, linear regression: c=0.14, 95% confidence interval 0.05-0.30, P<0.001) and HDL-C ≥1.0 (increase of 0.002 mmol/L, linear regression: reference category). A similar relationship between change in HDL-C and baseline HDL-C was observed within groups stratified by patient characteristics (apart from those on concurrent statin therapy and females). CONCLUSIONS: Our results may explain the discrepancies observed in some randomized controlled trials whereby subgroup analysis of patients with the metabolic syndrome appeared to show benefit whereas this was absent in the total cohort. Thus, future interventional studies using fibrates should perhaps focus on patients with low HDL-C levels.

Growth differentiation factor-15 predicts mortality and morbidity after cardiac resynchronization therapy.

AIMS: The aim of this study was to determine whether growth differentiation factor-15 (GDF-15) predicts mortality and morbidity after cardiac resynchronization therapy (CRT). Growth differentiation factor-15, a transforming growth factor-beta-related cytokine which is up-regulated in cardiomyocytes via multiple stress pathways, predicts mortality in patients with heart failure treated pharmacologically. METHODS AND RESULTS: Growth differentiation factor-15 was measured before and 360 days (median) after implantation in 158 patients with heart failure [age 68 +/- 11 years (mean +/- SD), left ventricular ejection fraction (LVEF) 23.1 +/- 9.8%, New York Class Association (NYHA) class III (n = 117) or IV (n = 41), and QRS 153.9 +/- 28.2 ms] undergoing CRT and followed up for a maximum of 5.4 years for events. In a stepwise Cox proportional hazards model with bootstrapping, adopting log GDF-15, log NT pro-BNP, LVEF, and NYHA class as independent variables, only log GDF-15 [hazard ratio (HR), 3.76; P = 0.0049] and log NT pro-BNP (HR, 2.12; P = 0.0171) remained in the final model. In the latter, the bias-corrected slope was 0.85, the optimism (O) was -0.06, and the c-statistic was 0.74, indicating excellent internal validity. In univariate analyses, log GDF-15 [HR, 5.31; 95% confidence interval (CI), 2.31-11.9; likelihood ratio (LR) chi(2) = 14.6; P < 0.0001], NT pro-BNP (HR, 2.79; 95% CI, 1.55-5.26; LR chi(2) = 10.4; P = 0.0004), and the combination of both biomarkers (HR, 7.03; 95% CI, 2.91-17.5; LR chi(2) = 19.1; P < 0.0001) emerged as significant predictors. The biomarker combination was associated with the highest LR chi(2) for all endpoints. CONCLUSION: Pre-implant GDF-15 is a strong predictor of mortality and morbidity after CRT, independent of NT pro-BNP. The predictive value of these analytes is enhanced by combined measurement.

A prospective study in primary care in patients without vascular disease comparing levels of coronary risk factors in those recommended for lipid-lowering drugs based on either absolute risk or absolute risk reduction.

In the United Kingdom, the current recommendation is that lipid-lowering drugs should be prescribed for primary prevention only to subjects with an absolute coronary risk (AR) greater than 15% in 5 years (i.e., myocardial infarction or angina). However, to achieve greater benefit it may be preferable to direct treatment to those patients showing the greatest absolute risk reduction (ARR). The aim of this study was to compare the characteristics of subjects eligible for lipid-lowering drugs based on the AR criteria or on an ARR of >4.45%. A prospective study was carried out over 29 months in primary care in a part of the United Kingdom with a prevalence of coronary disease nearly 20% above the national average. Risk factors were recorded in men and women aged 30-75 years who were being considered by their primary care physician for lipid-lowering drug therapy. Of the 2351 patients included in the study, 2139 (91%) and 101 (4.3%) were, respectively, below and above the criteria for treatment by both AR and ARR criteria. In 111 (4.7%) subjects, treatment was recommended based on only one of the criteria-82 on AR and 29 on ARR. Comparing these two groups, those treated on AR only were older (mean age 68.1 years [SD, 4.1] vs. 49.1 years [SD, 4.6]; p<0.0001) and had a lower total cholesterol (260 vs. 288 mg/dL; p=0.015); higher high-density lipoprotein cholesterol (50 vs. 43 mg/dL; p=0.003), lower low-density lipoprotein cholesterol (160 vs. 184 mg/dL; p=0.03), a lower total to high-density lipoprotein cholesterol ratio (5.4 vs. 7.1; p<0.0001), and lower triglycerides (258 vs. 435 mg/dL; p=0.007). The AR group also had a higher mean systolic blood pressure (170.9 vs. 158.9 mm Hg; p=0.013), presumably an attribute of their greater age. Although the AR and ARR groups did not show a difference in the proportion of males or diabetics, there was a significantly greater proportion of smokers in the latter group (72% vs. 35%; p=0.001). In conclusion, treatment recommendations based on AR alone would result in nontreatment of young subjects with significant hyperlipidemia and at high relative risk of coronary disease, whereas lipid-lowering drugs would be given preferentially to patients whose main coronary heart disease risk factors are age and hypertension but not hyperlipidemia. By contrast, treatment recommendations based on ARR ensure that lipid-lowering drugs are directed to patients who will derive the most benefit. Furthermore, delaying treatment in younger subjects at high relative risk but not high AR results in their accumulating significant coronary risk in the years before their AR exceeds an arbitrary threshold before lipid-lowering drugs are prescribed.