Hemoglobin A1c and abdominal obesity as predictors of diabetes and ASCVD in individuals with prediabetes in UK Biobank: a prospective observational study.

Objectives: Whether "prediabetes" merits particular clinical attention beyond the management of associated risk factors is controversial, particularly given the expansion of the definition of prediabetes from HbA1c 6.0-6.4% to 5.

Dysregulated nicotinamide adenine dinucleotide metabolome in patients hospitalized with COVID-19.

Nicotinamide adenine dinucleotide (NAD) depletion has been postulated as a contributor to the severity of COVID-19; however, no study has prospectively characterized NAD and its metabolites in relation to disease severity in patients with COVID-19. We measured NAD and its metabolites in 56 hospitalized patients with COVID-19 and in two control groups without COVID-19: (1) 31 age- and sex-matched adults with comorbidities, and (2) 30 adults without comorbidities. Blood NAD concentrations in COVID-19 group were only slightly lower than in the control groups (p < 0.

Discordance Analysis of VLDL-C and ApoB in UK Biobank and Framingham Study: A Prospective Observational Study.

Background: Recent observational and Mendelian randomization analyses have reported significant effects of VLDL-C (very-low density lipoprotein cholesterol) on risk that is independent of ApoB (apolipoprotein B). We aim to determine the independent association of VLDL-C and ApoB with the risk of new onset cardiovascular events in the UK Biobank and Framingham Heart Study cohorts.

Methods: We included 294 289 UK Biobank participants with a median age of 56 years, 42% men, and 2865 Framingham Heart Study participants (median age, 53 years; 47% men).

Modulation of circulating free testosterone fraction by testosterone, dihydrotestosterone, and estradiol during testosterone replacement therapy.

Background: Testosterone, estradiol, and dihydrotestosterone share common ligand binding sites on sex hormone binding globulin and albumin. It is unknown whether and how changes in testosterone, dihydrotestosterone, and estradiol concentrations during testosterone replacement therapy affect free testosterone fraction.

Objective: To determine the effect of changes in testosterone, dihydrotestosterone, and estradiol concentrations on free testosterone fraction during testosterone replacement therapy of men with hypogonadism.

The Causal-Benefit Model to Prevent Cardiovascular Events.

Selecting individuals for preventive lipid-lowering therapy is presently governed by the 10-year risk model. Once a prespecified level of cardiovascular disease risk is equaled or exceeded, individuals become eligible for preventive lipid-lowering therapy. A key limitation of this model is that only a small minority of individuals below the age of 65 years are eligible for therapy.

Discordance among apoB, non-high-density lipoprotein cholesterol, and triglycerides: implications for cardiovascular prevention.

Background And Aims: Despite growing evidence that apolipoprotein B (apoB) is the most accurate marker of atherosclerotic cardiovascular disease (ASCVD) risk, its adoption in clinical practice has been low. This investigation sought to determine whether low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (HDL-C), and triglycerides are sufficient for routine cardiovascular care.

Methods: A sample of 293 876 UK Biobank adults (age: 40-73 years, 42% men), free of cardiovascular disease, with a median follow-up for new-onset ASCVD of 11 years was included.

Bone microarchitectural alterations associated with spinal cord injury: Relation to sex hormones, metabolic factors, and loading.

Context: People living with spinal cord injury (SCI) are at high risk for bone fractures. Neural, hormonal and metabolic contributors to bone microarchitectural alterations are incompletely understood.

Objective: To determine the relationship of physical, metabolic and endocrine characteristics with bone microarchitecture, characterized using high-resolution peripheral quantitative computed tomography (HRpQCT) in SCI.

Effect of Testosterone on Progression From Prediabetes to Diabetes in Men With Hypogonadism: A Substudy of the TRAVERSE Randomized Clinical Trial.

Importance: The effect of testosterone replacement therapy (TRT) in men with hypogonadism on the risk of progression from prediabetes to diabetes or of inducing glycemic remission in those with diabetes is unknown.

Objective: To evaluate the efficacy of TRT in preventing progression from prediabetes to diabetes in men with hypogonadism who had prediabetes and in inducing glycemic remission in those with diabetes.

Design, Setting, And Participants: This nested substudy, an intention-to-treat analysis, within a placebo-controlled randomized clinical trial (Testosterone Replacement Therapy for Assessment of Long-Term Vascular Events and Efficacy Response in Hypogonadal Men [TRAVERSE]) was conducted at 316 trial sites in the US.

Depressive Syndromes in Men With Hypogonadism in the TRAVERSE Trial: Response to Testosterone-Replacement Therapy.

Context: The effect of testosterone on depressive symptoms in men with hypogonadism remains incompletely understood.

Objective: We assessed the effects of testosterone-replacement therapy (TRT) in improving depressive symptoms in hypogonadal men with and without depressive symptoms enrolled in the TRAVERSE cardiovascular safety trial.

Methods: A randomized, placebo-controlled, double-blind study was conducted at 316 trial sites.

Prostate Safety Events During Testosterone Replacement Therapy in Men With Hypogonadism: A Randomized Clinical Trial.

Importance: The effect of testosterone replacement therapy (TRT) on the risk of prostate cancer and other adverse prostate events is unknown.

Objective: To compare the effect of TRT vs placebo on the incidences of high-grade prostate cancers (Gleason score ≥4 + 3), any prostate cancer, acute urinary retention, invasive prostate procedures, and pharmacologic treatment for lower urinary tract symptoms in men with hypogonadism.

Design, Setting, And Participants: This placebo-controlled, double-blind randomized clinical trial enrolled 5246 men (aged 45-80 years) from 316 US trial sites who had 2 testosterone concentrations less than 300 ng/dL, hypogonadal symptoms, and cardiovascular disease (CVD) or increased CVD risk.

Efficacy of Testosterone Replacement Therapy in Correcting Anemia in Men With Hypogonadism: A Randomized Clinical Trial.

Importance: Testosterone deficiency causes mild anemia. Whether testosterone replacement therapy (TRT) can correct anemia or prevent the development of anemia in men with hypogonadism remains incompletely understood.

Objective: To assess the efficacy of TRT in correcting anemia in men with hypogonadism and anemia, and reducing the risk of developing anemia in those without anemia.

Effect of Testosterone Replacement Therapy on Sexual Function and Hypogonadal Symptoms in Men with Hypogonadism.

Context: Few long-term randomized trials have evaluated the efficacy of testosterone replacement therapy (TRT) in improving sexual function and hypogonadal symptoms in men with hypogonadism and whether effects are sustained beyond 12 months.

Objective: The Testosterone Replacement therapy for Assessment of long-term Vascular Events and efficacy ResponSE in hypogonadal men (TRAVERSE) study evaluated the effect of TRT on major adverse cardiovascular events in middle-aged and older men with hypogonadism. The Sexual Function Study, nested within the parent trial, determined testosterone's efficacy in improving sexual activity, hypogonadal symptoms, libido, and erectile function among men reporting low libido.

Cardiovascular Safety of Testosterone-Replacement Therapy.

Background: The cardiovascular safety of testosterone-replacement therapy in middle-aged and older men with hypogonadism has not been determined.

Methods: In a multicenter, randomized, double-blind, placebo-controlled, noninferiority trial, we enrolled 5246 men 45 to 80 years of age who had preexisting or a high risk of cardiovascular disease and who reported symptoms of hypogonadism and had two fasting testosterone levels of less than 300 ng per deciliter. Patients were randomly assigned to receive daily transdermal 1.

Is hypertriglyceridemia a reliable indicator of cholesterol-depleted Apo B particles?

Objectives: Because cholesterol-depleted Apo B particles are thought to be a hallmark of hypertriglyceridemia, American, Canadian and European Lipid Guidelines suggest screening for Apo B only in patients with hypertriglyceridemia. Accordingly, this study examines the relationship of triglycerides to the LDL-C/Apo B and non-HDL-C/Apo B ratios.

Methods: The study cohort consisted of 6272 NHANES subjects adjusted for a weighted sample size of 150 million subjects without previously diagnosed cardiac disease.

Nicotinamide Adenine Dinucleotide Augmentation in Overweight or Obese Middle-Aged and Older Adults: A Physiologic Study.

Context: Nicotinamide adenine dinucleotide (NAD) levels decline with aging and age-related decline in NAD has been postulated to contribute to age-related diseases.

Objective: We evaluated the safety and physiologic effects of NAD augmentation by administering its precursor, β-nicotinamide mononucleotide (MIB-626, Metro International Biotech, Worcester, MA), in adults at risk for age-related conditions.

Methods: Thirty overweight or obese adults, ≥ 45 years, were randomized in a 2:1 ratio to 2 MIB-626 tablets each containing 500 mg of microcrystalline β-nicotinamide mononucleotide or placebo twice daily for 28 days.

Circulating dihydrotestosterone, testosterone, and free testosterone levels and dihydrotestosterone-to-testosterone ratios in healthy women across the menstrual cycle.

Objective: To characterize the circulating androgen levels across the menstrual cycle in healthy women using highly sensitive and accurate methods and report sex differences in the relative levels of dihydrotestosterone (DHT) to testosterone (T) levels.

Design: Prospective cohort study.

Setting: Research clinic, academic teaching hospital.

Interplay of Atherogenic Particle Number and Particle Size and the Risk of Coronary Heart Disease.

Background: We examined the interplay of apolipoprotein B (apoB) and LDL particle size, approximated by the LDL-cholesterol (LDL-C)/apoB ratio, on the risk of new-onset coronary heart disease (CHD).

Methods: Participants without cardiovascular disease from the UK Biobank (UKB; n = 308 182), the Women's Health Study (WHS; n = 26 204), and the Framingham Heart Study (FHS; n = 2839) were included. Multivariable Cox models were used to assess the relationship between apoB and LDL-C/apoB ratio and incidence of CHD (14 994 events).

Reference intervals for free testosterone in adult men measured using a standardized equilibrium dialysis procedure.

Background: Free testosterone (FT) determination may be helpful in evaluating men suspected of testosterone deficiency especially in conditions with altered binding-protein concentrations. However, methods for measuring FT by equilibrium dialysis and reference intervals vary among laboratories.

Objective: To determine reference intervals for FT in healthy, nonobese men by age groups as well as in healthy young men, 19-39 years, using a standardized equilibrium dialysis procedure METHODS: We measured FT in 145 healthy, nonobese men, 19 years or older, using a standardized equilibrium dialysis method performed for 16-h at 37°C using undiluted serum and dialysis buffer that mimicked the ionic composition of human plasma.

Testosterone replacement in prostate cancer survivors with testosterone deficiency: Study protocol of a randomized controlled trial.

Background: Most men diagnosed with prostate cancer today have organ-confined disease and low risk of disease recurrence after radical prostatectomy. Testosterone deficiency in prostate cancer survivors contributes to impaired health-related quality of life but testosterone treatment is viewed as a contraindication in this population.

Objectives: We describe the design of the first randomized trial to determine the safety and efficacy of testosterone treatment in men who have undergone prostatectomy for non-aggressive prostate cancer and have symptomatic testosterone deficiency.

An adverse lipoprotein phenotype-hypertriglyceridaemic hyperapolipoprotein B-and the long-term risk of type 2 diabetes: a prospective, longitudinal, observational cohort study.

Background: This study examines the risk of new-onset diabetes in patients with hypertriglyceridaemic hyperapolipoprotein B (high triglycerides, high apolipoprotein B [apoB], low LDL cholesterol to apoB ratio, and low HDL cholesterol). The aim was to establish whether this lipoprotein phenotype identified a substantial group at high risk of developing diabetes over the next 20 years.

Methods: In this prospective, longitudinal, observational cohort study, we used data from the Framingham Offspring cohort (recruited in Framingham, MA, USA).

Effect of Selective Androgen Receptor Modulator on Cholesterol Efflux Capacity, Size, and Subspecies of HDL Particles.

Context: Selective androgen receptor modulators (SARMs), because of their preferential muscle vs prostate selectivity, are being developed for muscle-wasting conditions. Oral SARMs suppress high-density lipoprotein cholesterol (HDL-C) but their effects on functional capacity and atherogenic potential of HDL particles are unknown.

Objective: To determine the effects of an oral SARM (OPK-88004) on cholesterol efflux capacity, HDL particle number and size, apolipoprotein particle number and size and HDL subspecies.

Accurate Measurement and Harmonized Reference Ranges for Total and Free Testosterone Levels.

Diagnosing testosterone deficiency requires accurate and precise measurement of total testosterone levels by an accurate method, such as liquid chromatography-tandem mass spectrometry in a laboratory certified by an accuracy-based program (eg, Centers for Disease Control and Prevention's Hormone Standardization (HoST) Program), and, if needed, free testosterone level. Free testosterone level should ideally be measured by equilibrium dialysis method. Testosterone levels should be measured in 2 or more fasting samples obtained in the morning.

MIB-626, an Oral Formulation of a Microcrystalline Unique Polymorph of β-Nicotinamide Mononucleotide, Increases Circulating Nicotinamide Adenine Dinucleotide and its Metabolome in Middle-Aged and Older Adults.

Background: Nicotinamide adenine dinucleotide (NAD) precursors, nicotinamide mononucleotide (NMN), or nicotinamide riboside (NR) extend healthspan and ameliorate some age-related conditions in model organisms. However, early-phase trials of NAD precursors have yielded varying results and their pharmacokinetics remain incompletely understood. Here, we report the pharmacokinetics and pharmacodynamics of MIB-626, a microcrystalline unique polymorph βNMN formulation.

Reduced Levels of NAD in Skeletal Muscle and Increased Physiologic Frailty Are Associated With Viral Coinfection in Asymptomatic Middle-Aged Adults.

Background: People living with HIV (PLWH) are disproportionately burdened with multimorbidity and decline in physiologic function compared with their uninfected counterparts, but biological mechanisms that differentially contribute to the decline in muscle function in PLWH compared with uninfected people remain understudied.

Setting: The study site was Brigham and Women's Hospital, Harvard Medical School, Boston, MA.

Methods: We evaluated skeletal muscle tissue for levels of total nicotinamide adenine dinucleotide (NAD), NAD+, and nicotinamide adenine dinucleotide (NADH) in middle-aged asymptomatic PLWH, coinfected with hepatitis C virus and/or cytomegalovirus and compared them with uninfected control participants.