Improvement of endothelial function following initiation of testosterone replacement therapy

Transformation or replacement - Effects of hormone therapy on cardiovascular risk

Hormone therapy (HT) is important and frequently used both regarding replacement therapy (HRT) and gender affirming therapy (GAHT). While HRT has been effective in addressing symptoms related to hormone shortage, several side effects have been described. In this context, there are some studies that show increased cardiovascular risk. However, there are also studies reporting protective aspects of HT. Nevertheless, the exact impact of HT on cardiovascular risk and the underlying mechanisms remain poorly understood. This article explores the relationship between diverse types of HT and cardiovascular risk, focusing on mechanistic insights of the underlying hormones on platelet and leukocyte function as well as on effects on endothelial and adipose tissue cells.

Testosterone and Exercise in Middle-to-Older Aged Men: Combined and Independent Effects on Vascular Function

[Figure: see text].

Sex differences in vascular aging in response to testosterone

Large elastic arterial stiffening and endothelial dysfunction are phenotypic characteristics of vascular aging, a major risk factor for age-associated cardiovascular diseases. Compared to men, vascular aging in women appears to be slowed until menopause, whereafter vascular aging accelerates to match that seen in men. These sex differences in vascular aging have been attributed to changes in sex hormones that occur with aging. Although the role of estradiol in vascular aging in women has been highlighted in recent aging research, little is known about the impact of declining testosterone concentrations in both sexes. Importantly, while androgen concentrations generally decline with age in men, there are data that indicate reductions in androgen concentrations in women as well. Evidence suggests that low testosterone is associated with impaired endothelial function and increased arterial stiffness in men, although the effect of androgens on vascular aging in women remains unclear. Testosterone may modulate vascular aging by mitigating the effects of oxidative stress and inflammation, although there is sex specificity to this effect. The purpose of this review is to present and summarize the research regarding sex differences in vascular aging in response to androgens, specifically testosterone. Because exercise is a potent lifestyle factor for slowing and reversing vascular aging, we briefly summarize the available literature regarding the regulatory function of testosterone on vascular adaptations to exercise training.

Vascular Dysfunction among Malaysian Men with Increased BMI: An Indication of Synergistic Effect of Free Testosterone and Inflammation

Background and objectives: Obesity is associated with poor vascular function and may lead to future cardiovascular disease (CVD). Obesity is also related to increased inflammation and a low testosterone level. This study was conducted to determine the relationship between inflammation, testosterone level, and vascular function among subjects with an increased body mass index (BMI) and to determine whether both low testosterone and high inflammation have synergistic effects towards vascular dysfunction. Materials and Methods: A total of 303 men aged 40-80 years were recruited from Klang Valley, Malaysia. Their height, weight, blood pressure (BP), lipid, blood glucose level, total testosterone (TT), free testosterone (FT), and C-reactive protein (CRP) were measured. The carotid femoral pulse wave velocity (PWVCF) and augmentation index (AI) were also recorded as markers of vascular function. Results: The mean age of all the subjects was 54.46 ± 9.77 years. Subjects were divided into a low/normal body mass index (BMI) group (BMI < 25 kg/m2; NG, n = 154) and high BMI group (BMI ≥ 25 kg/m2; OG, n = 149). The mean BMI for NG was 22.20 ± 1.94 kg/m2 while for OG was 28.87 ± 3.24 kg/m2 (p < 0.01). The level of TT (OG = 21.13 ± 6.44 versus NG = 16.18 ± 6.16 nmol/L, p < 0.01) and FT (OG = 0.34 ± 0.12 versus NG = 0.39 ± 0.11 nmol/L, p < 0.01) were reduced while the level of CRP [OG = 1.05 (2.80) versus NG = 0.50 (1.50) mmol/L, p = 0.01] was increased in OG compared to NG. PWVCF (OG = 8.55 ± 1.34 versus NG = 8.52 ± 1.42 m/s, p = 0.02) and AI (OG = 16.91% ± 6.00% versus 15.88% ± 5.58%, p < 0.01) were significantly increased in OG after adjustment for other CVD risk factors. The subjects that had both a low FT and an increased CRP had higher AI when compared to those with a high CRP and high FT (p < 0.01). Conclusions: The increased BMI was associated with vascular dysfunction, mediated by a low testosterone level and increased inflammation. Furthermore, having both conditions concurrently lead to higher vascular dysfunction. Weight loss, testosterone supplementation, and the anti-inflammatory agent may be beneficial for men to prevent vascular dysfunction.

New insights into arterial stiffening: does sex matter?

This review discusses sexual dimorphism in arterial stiffening, disease pathology interactions, and the influence of sex on mechanisms and pathways. Arterial stiffness predicts cardiovascular mortality independent of blood pressure. Patients with increased arterial stiffness have a 48% higher risk for developing cardiovascular disease. Like other cardiovascular pathologies, arterial stiffness is sexually dimorphic. Young women have lower stiffness than aged-matched men, but this sex difference reverses during normal aging. Estrogen therapy does not attenuate progressive stiffening in postmenopausal women, indicating that currently prescribed drugs do not confer protection. Although remodeling of large arteries is a protective adaptation to higher wall stress, arterial stiffening increases afterload to the left ventricle and transmits higher pulsatile pressure to smaller arteries and target organs. Moreover, an increase in aortic stiffness may precede or exacerbate hypertension, particularly during aging. Additional studies are needed to elucidate the mechanisms by which females are protected from arterial stiffness to provide insight into its mechanisms and, ultimately, therapeutic targets for treating this pathology.

Benefits and Health Implications of Testosterone Therapy in Men With Testosterone Deficiency

INTRODUCTION

Testosterone (T) deficiency (TD; hypogonadism) has deleterious effects on men's health; negatively affects glycometabolic and cardiometabolic functions, body composition, and bone mineral density; contributes to anemia and sexual dysfunction; and lowers quality of life. T therapy (TTh) has been used for the past 8 decades to treat TD, with positive effects on signs and symptoms of TD.

AIM

To summarize the health benefits of TTh in men with TD.

METHODS

A comprehensive literature search was carried out using PubMed, articles relevant to TTh were accessed and evaluated, and a comprehensive summary was synthesized.

MAIN OUTCOME MEASURES

Improvements in signs and symptoms of TD reported in observational studies, registries, clinical trials, and meta-analyses were reviewed and summarized.

RESULTS

A large body of evidence provides significant valuable information pertaining to the therapeutic value of TTh in men with TD. TTh in men with TD provides real health benefits for bone mineral density, anemia, sexual function, glycometabolic and cardiometabolic function, and improvements in body composition, anthropometric parameters, and quality of life.

CONCLUSION

TTh in the physiologic range for men with TD is a safe and effective therapeutic modality and imparts great benefits on men's health and quality of life. Traish AM. Benefits and Health Implications of Testosterone Therapy in Men With Testosterone Deficiency. Sex Med Rev 2018;6:86-105.

Androgens and cardiovascular disease in women and men

Cardiovascular disease is the leading cause of death in both women and men. Its pathogenesis is multifactorial, with sex hormones playing an important role. Androgens have both direct and indirect effects on the vasculature. This review summarizes evidence on the association of both endogenous and exogenous androgens with subclinical and overt cardiovascular disease in women and men. Concerning women, both high and low levels of endogenous androgens have been associated with cardiovascular disease, while other studies have reported no association. Adiposity, impaired glucose metabolism, dyslipidemia and estrogen levels may mediate the observed associations. Regarding testosterone therapy in women, there have been no large prospective studies on cardiovascular outcomes. Concerning men, most studies indicate that low levels of circulating testosterone are associated with increased rates of cardiovascular disease in the general population; the causality, however, of this association remains to be proven. Testosterone replacement therapy in men with symptoms of hypogonadism and low serum testosterone merits caution with regard to cardiovascular safety, as evidence is still conflicting.