The role of estrogens in men and androgens in women

The impact of gender on survival outcomes in patients with small intestinal stromal tumors: a comprehensive analysis using the SEER database

BACKGROUND

Small intestinal stromal tumors (SISTs) are a rare type of mesenchymal tumor. Gender is known to influence the incidence and prognosis of various tumors, but its role on the survival of SISTs at the population level remains unclear. Therefore, we aim to explore the relationship between gender and the prognosis of SISTs using the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Data on SISTs patients from 2000 to 2019 were derived from the SEER database. Multiple imputation was used to address missing data. Kaplan-Meier analyses and Cox proportional hazard models were applied to evaluate the impact of demographic and clinical characteristics on overall survival (OS) and cancer-specific survival (CSS).

RESULTS

A total of 3513 patients with SISTs were analyzed, including 1921 males and 1592 females. Kaplan-Meier analysis coupled with log-rank testing demonstrated a significantly higher mortality rate among male patients compared to females (P < 0.001). Notably, female patients exhibited superior OS (hazard ratio [HR] 0.808, 95% confidence interval [CI] 0.724-0.902, P < 0.001) and CSS (HR 0.801, 95% CI 0.692-0.927, P = 0.003) compared to male patients. While the mean 1-year CSS rates were comparable between genders (95.3% for males vs. 96.0% for females, P = 0.332), male patients consistently showed lower mean survival rates at 3-, 5-, and 10-year intervals. Surgical intervention significantly boosted 5-year OS and CSS rates in both male and female patients (P < 0.001). Multivariate Cox regression analysis identified age, sex, grade, TNM stage, surgery, and mitotic rate as independent risk factors for OS and CSS in patients with SISTs.

CONCLUSIONS

Our findings suggest that male patients with SISTs have a higher risk of mortality compared to female patients, indicating that gender may serve as a predictive indicator for survival in this patient population.

Impaired Prolactin-Lowering Effects of Metformin in Women with Polycystic Ovary Syndrome

The effect of metformin on prolactin concentration seems to be sex-dependent. The aim of this study was to determine whether the androgen status modulates the impact of metformin on plasma prolactin levels in women. This study included two matched groups of prediabetic women with hyperprolactinemia: 25 with PCOS and 25 control subjects with androgen levels within the reference range and with normal ovarian morphology. Glucose homeostasis markers, prolactin, the remaining anterior pituitary hormones, sex hormones, SHBG and IGF-1 were determined before and after six months of metformin treatment. At baseline, both groups differed in LH, LH/FSH ratio, testosterone, FAI, DHEA-S, androstenedione and estradiol. Although metformin improved insulin sensitivity and increased SHBG in both study groups, these effects were more pronounced in control subjects than in women with PCOS. In control subjects, the drug decreased total and monomeric prolactin and increased LH. In women with PCOS, metformin reduced LH, LH/FSH ratio, testosterone and FAI. In the control group, the impact on total and monomeric prolactin positively correlated with their baseline levels and with the degree of improvement in insulin sensitivity, as well as negatively correlated with testosterone and FAI. In women with PCOS, treatment-induced changes in testosterone and FAI positively correlated with the changes in LH and LH/FSH ratio. The obtained results suggest that the prolactin-lowering properties of metformin are less pronounced in women with coexisting PCOS than in women with elevated prolactin levels, probably owing to the increased production of endogenous testosterone.

Dimethandrolone Undecanoate, a Novel, Nonaromatizable Androgen, Increases P1NP in Healthy Men Over 28 Days

CONTEXT

Dimethandrolone undecanoate (DMAU) is being developed as a male contraceptive. Daily oral administration of DMAU, a potent androgen that is not aromatized, markedly suppresses serum testosterone (T) and estradiol (E2) in healthy men. E2 deficiency can increase bone resorption in men.

OBJECTIVE

This work aimed to assess changes in bone turnover markers with DMAU administration in a 28-day study.

DESIGN

A randomized, double-blind, placebo-controlled study was conducted.

SETTING

This study took place at 2 academic medical centers.

PARTICIPANTS

Healthy men, age 18 to50 years (n = 81), participated.

INTERVENTION

Men received 0, 100, 200, or 400 mg of oral DMAU for 28 days. Serum C-terminal telopeptide of type I collagen (CTX; bone resorption marker) and procollagen type I amino-terminal propeptide (P1NP; bone formation marker) were measured on days 1 and 28.

MAIN OUTCOME MEASURES

Changes in bone turnover markers and serum hormones over the treatment period were measured.

RESULTS

On day 28, median serum T and E2 were markedly suppressed in all treatment groups vs placebo (P < .001 for both). Percentage change (%) in serum P1NP significantly differed across treatment groups (P = .007): Serum P1NP significantly increased in the 200 mg (5%, interquartile range [IQR] -7% to 27%) and 400 mg (22%, IQR -1% to 40%) groups relative to placebo (-8%, IQR -20% to 0%). Change (%) in serum CTX did not differ between groups (P = .09).

CONCLUSIONS

DMAU administration for 28 days to healthy men leads to marked suppression of serum T and E2, yet increases P1NP, a serum marker of bone formation. Longer-term studies of the potent androgen DMAU are warranted to determine its impact on bone health in men.

Epidemiology and management of osteoporosis in the People's Republic of China: current perspectives

With the progressive aging of the population, osteoporosis has gradually grown into a global health problem for men and women aged 50 years and older because of its consequences in terms of disabilities and fragility fractures. This is especially true in the People's Republic of China, which has the largest population and an increasing proportion of elderly people, as osteoporosis has become a serious challenge to the Chinese government, society, and family. Apart from the fact that all osteoporotic fractures can increase the patient's morbidity, they can also result in fractures of the hip and vertebrae, which are associated with a significantly higher mortality. The cost of osteoporotic fractures, moreover, is a heavy burden on families, society, and even the country, which is likely to increase in the future due, in part, to the improvement in average life expectancy. Therefore, understanding the epidemiology of osteoporosis is essential and is significant for developing strategies to help reduce this problem. In this review, we will summarize the epidemiology of osteoporosis in the People's Republic of China, including the epidemiology of osteoporotic fractures, focusing on preventive methods and the management of osteoporosis, which consist of basic measures and pharmacological treatments.

Single, escalating dose pharmacokinetics, safety and food effects of a new oral androgen dimethandrolone undecanoate in man: a prototype oral male hormonal contraceptive

The novel androgen, dimethandrolone (DMA) has both androgenic and progestational activities, properties that may maximize gonadotropin suppression. We assessed the pharmacokinetics of dimethandrolone undecanoate (DMAU), an orally bioavailable, longer acting ester of DMA, for male contraceptive development. Our objective was to examine the safety and pharmacokinetics of single, escalating doses of DMAU (powder in capsule formulation) administered orally with or without food in healthy men. We conducted a randomized, double-blind Phase 1 study. For each dose of DMAU (25-800 mg), 10 male volunteers received DMAU and two received placebo at two academic medical centres. DMAU was administered both fasting and after a high-fat meal (200-800 mg doses). Serial serum samples were collected over 24 h following each dose. DMAU was well tolerated without significant effects on vital signs, safety laboratory tests or electrocardiograms. When administered while fasting, serum DMA (active compound) was detectable in only 4/10 participants after the 800 mg dose. When administered with a 50% fat meal, serum DMA was detectable in all participants given 200 mg DMAU and showed a dose-incremental increase up to 800 mg, with peak levels 4-8 h after taking the dose. Serum gonadotropins and sex hormone concentrations were significantly suppressed 12 h after DMAU administration with food at doses above 200 mg. This first-in-man study demonstrated that a single, oral dose of DMAU up to 800 mg is safe. A high-fat meal markedly improved DMAU/DMA pharmacokinetics.

Bone mineral density and vitamin D in PCOS and hirsutism

Polycystic ovary syndrome (PCOS) is the most frequent endocrinopathy in reproductive-aged women. The majority of hirsute patients are diagnosed with PCOS. Hyperandrogenemia, central obesity and insulin resistance may protect patients with PCOS from osteoporosis, whereas increased cortisol levels, low growth hormone and amenorrhea may be associated with decreased bone mineral density (BMD). Recent studies suggested that insulin resistance in PCOS is associated with decreased vitamin D levels that could not be explained by obesity alone. Vitamin D treatment may therefore have positive effects on insulin sensitivity and perhaps also hyperandrogenemia in patients with PCOS. In the present article, we review the evidence of changed BMD, bone mineral turnover and vitamin D status in PCOS and hirsutism compared with healthy women and the effects of medical intervention on BMD in PCOS.

Role of medicinal plants and natural products on osteoporotic fracture healing

Popularly known as “the silent disease” since early symptoms are usually absent, osteoporosis causes progressive bone loss, which renders the bones susceptible to fractures. Bone fracture healing is a complex process consisting of four overlapping phases—hematoma formation, inflammation, repair, and remodeling. The traditional use of natural products in bone fractures means that phytochemicals can be developed as potential therapy for reducing fracture healing period. Located closely near the equator, Malaysia has one of the world's largest rainforests, which are homes to exotic herbs and medicinal plants. Eurycoma longifolia (Tongkat Ali), Labisia pumila (Kacip Fatimah), and Piper sarmentosum (Kaduk) are some examples of the popular ethnic herbs, which have been used in the Malay traditional medicine. This paper focuses on the use of natural products for treating fracture as a result of osteoporosis and expediting its healing.

The effects of systemic chemical sympathectomy on local bone loss induced by sciatic neurectomy

BACKGROUND

It has been suggested that the sympathetic nervous system (SNS) is involved in bone metabolism and that blockade of the SNS could reduce bone loss and stimulate bone formation. However, the question of whether suppression of SNS tone could compensate for mechanical unloading-induced bone loss must be further clarified. The purpose of this study was to investigate whether systemically inhibiting sympathetic nervous system (SNS) tone could prevent bone loss from mechanical-inactivity-induced osteopenia.

METHODS

Female Wistar rats (12 weeks old) were randomly assigned to three groups: the SN group (n = 10), or single leg sciatic neurectomy group; the SNP group (n = 12), or single leg sciatic neurectomy + propranolol treatment (0.5 g/L in dietary water) group; and the CON group (n = 10), or single leg sham-operated group. Animals were fed with distilled water or propranolol in water, in accordance with their group design, for 30 days. Histomorphometry, geometry, tissue weight, and serum markers were assessed.

RESULTS

Propranolol-treated animals drank significantly less water, but did not differ in daily chow consumption or body weight gain. In histomorphometric analysis, the spongy bone volume ratio in proximal tibiae was significantly lower in the two sciatic neurectomy groups, but there was no difference between the SN and SNP groups. Architecture analysis showed that the SN group had significantly thinner trabeculae and fewer trabeculae than the CON group (p < 0.05), but there was no difference between the SNP and CON groups. There were no significant differences for tissue weight, geometric measurement, or serum markers assay.

CONCLUSION

It was observed that blockade of the SNS prevented neurectomy-induced bone resorption, as demonstrated by various histomorphometric data, although the difference between SN and SNP did not reach significance. In further work it would be valuable to study possible gender, age, and dose-dependent efficacy of propranolol on bone metabolism.

Male hormonal contraception: potential risks and benefits

An effective, safe, reversible, and acceptable method of contraception is an important component of reproductive health and provides the opportunity of shared responsibility for family planning for both partners. Female hormonal contraceptives have been proven to be safe, reversible, available and widely acceptable by different populations. In contrast, male hormonal contraception, despite significant progress showing contraceptive efficacy comparable to female hormonal methods during last three decades, has not yet led to an approved product. Safety of a pharmaceutical product is an appropriate concern but the majority of male hormonal contraceptive clinical trials have not reported significant short term safety concerns. While the absence of serious adverse effects is encouraging, the studies have been designed for efficacy endpoints not long term safety. In this review we summarize potential risks and benefits of putative male hormonal contraceptives on reproductive and non-reproductive organs. While the review covers what we believe will be the likely class of drugs used for male hormonal contraception a true assessment of long term risks and benefits cannot be achieved without an available product.

Reproductive hormones and bone

Hypothalamic gonadotropin-releasing hormone (GnRH) stimulates secretion of pituitary luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which directly regulate ovarian function. Pituitary FSH can modulate osteoclast development, and thereby influence bone turnover. Pituitary oxytocin and prolactin effects on the skeleton are not merely limited to pregnancy and lactation; oxytocin stimulates osteoblastogenesis and bone formation, whereas prolactin exerts skeletal effects in an age-dependent manner. Cyclic levels of inhibins and estrogen suppress FSH and LH, respectively, and also suppress bone turnover via their suppressive effects on osteoblast and osteoclast differentiation. However, continuous exposure to inhibins or estrogen/androgens is anabolic for the skeleton in intact animals and protects against gonadectomy-induced bone loss. Alterations of one hormone in the hypothalamic-pituitary-gonadal (HPG) axis influence other bone-active hormones in the entire feedback loop in the axis. Thus, we propose that the action of the HPG axis should be extended to include its combined effects on the skeleton, thus creating the HPG skeletal (HPGS) axis.

Associations of serum sex hormone-binding globulin and sex hormone concentrations with hip fracture risk in postmenopausal women

CONTEXT

Endogenous estradiol, testosterone, and SHBG may influence the risk of hip fracture.

DESIGN AND METHODS

From the Women's Health Initiative Observational Study, 39,793 eligible postmenopausal women did not have a previous hip fracture and were not using estrogen or other bone-active therapies. Of these, 400 who had a first-time nonpathological hip fracture (median follow-up, 7 yr) were matched to 400 controls by age, ethnicity, and baseline blood draw date. Estradiol, testosterone, and SHBG were measured in banked baseline serum.

RESULTS

Compared with women in the lowest tertiles, those with bioavailable testosterone in the highest tertile had a lower risk [odds ratio (OR) = 0.62; 95% confidence interval (CI) = 0.44-0.88]; those with bioavailable estradiol in the highest tertile had a lower risk (OR = 0.44; 95% CI = 0.29-0.66), and those with SHBG in the highest tertile had a higher risk (OR = 1.90; 95% CI = 1.31-2.74) of hip fracture. In models with all three hormones and potential confounders, high SHBG remained a strong independent risk factor (OR = 1.76; 95% CI = 1.12-2.78), high bioavailable testosterone remained protective (OR = 0.64; 95% CI = 0.40-1.00), but estradiol no longer was associated (OR = 0.72; 95% CI = 0.42-1.23).

CONCLUSIONS

High serum SHBG is associated with an increased risk of subsequent hip fracture and high endogenous testosterone with a decreased risk, independent of each other, serum estradiol concentration, and other putative risk factors. But endogenous estradiol has no independent association with hip fracture.

Secondary osteoporosis: a review of the recent evidence

OBJECTIVE

To review several causes of secondary osteoporosis as well as screening recommendations for underlying disorders.

METHODS

We conducted a review of the literature on many of the causes of osteoporosis that have been published during the past 15 years, focusing on those sources available from 2000 through the present. Indeed, more than two-thirds of the articles that we reviewed were printed during the past 6 years. These reports examined secondary osteoporosis in general, as well as many of the specific causes.

RESULTS

Secondary osteoporosis occurs in almost two-thirds of men, more than half of premenopausal and perimenopausal women, and about one-fifth of postmenopausal women. Its causes are vast, and they include hypogonadism, medications, hyperthyroidism, vitamin D deficiency, primary hyperparathyroidism, solid organ transplantation, gastrointestinal diseases, hematologic diseases, Cushing's syndrome, and idiopathic hypercalciuria. These causes have their own pathogenesis, epidemiologic features, and effect on the skeleton.

CONCLUSION

The causes of secondary osteoporosis are numerous, and an understanding of their characteristics with respect to bone density and potential fracture risk is essential in the management of osteoporosis. A heightened awareness of the possibility of their existence is necessary to provide optimal care.

Association analysis of estrogen receptor alpha gene polymorphisms with cross-sectional geometry of the femoral neck in Caucasian nuclear families

Bone geometry is a key factor in bone strength, which is the ultimate intrinsic determinant of fracture risk. Though the heritability of bone geometry is high, little effort has been spent on searching for the underlying genes. In this study, employing a sample of 1,873 subjects from 405 Caucasian nuclear families, we studied seven single nucleotide polymorphisms (SNPs) and their haplotypes of the ER-alpha gene for association with six hip geometric variables, namely, cross-sectional area (CSA), cortical thickness (CT), endocortical diameter (ED), subperiosteal width (W), sectional modulus (Z) and buckling ratio (BR). The major method used was the quantitative transmission disequilibrium test (QTDT). Our major findings were summarized below. The within-family association between SNP4 (rs1801132) in exon 4 with endocortical diameter and subperiosteal width was detected in single locus analyses (P=0.008 and 0.021, respectively) and verified in haplotype analyses (P=0.034 and 0.058, respectively). The total association of SNP4 with these two diameters was also observed in both single locus and haplotype analyses (P=0.005 and 0.031 for ED, plus P=0.003 and 0.070 for W). In addition, the total association between SNP5 (rs932477) in intron 4 with cortical thickness and buckling ratio was detected (single locus analyses: P=0.035 and 0.041, respectively). Haplotype analyses further supported the above association (P=0.010 and 0.004, respectively). Similar patterns of associations with the studied SNPs and their haplotypes were present in subsamples stratified by sex, too. However, after permutation tests, the empirical significance level was set as P<0.011, which renders most associations insignificant. Therefore, we concluded that polymorphisms in the ER-alpha gene were nominally associated with femoral neck (FN) geometry variables estimated from DXA. Such genetic effects on hip geometry were not sex specific.

LRP5 gene polymorphisms and idiopathic osteoporosis in men

Mutations in the low-density lipoprotein receptor-related protein 5 gene (LRP5) have demonstrated the role of LRP5 in bone mass acquisition. LRP5 variants were recently reported to contribute to the population-based variance in vertebral bone mass and size in males. To investigate whether LRP5 variants are implicated in idiopathic male osteoporosis, we studied 78 men with low BMD (<2.5 T score or < -2 Z score) aged less than 70 years (mean +/- SD: 50 +/- 16 years) in whom secondary causes of osteoporosis had been excluded and 86 controls (51 +/- 10 years). Genotypes and haplotypes were based on LRP5 missense substitutions in exons 9 (c.2047G > A, p.V667M) and 18 (c.4037C > T, p.A1330V), and their association with osteoporosis evaluated after adjustment for multiple clinical and environmental variables using logistic regression. The presence of osteoporosis was significantly associated with LRP5 haplotypes (P = 0.0036) independent of age (P = 0.006), weight (P = 0.004), calcium intake (P = 0.002), alcohol (P = 0.005) and tobacco (P = 0.004) consumption. Accordingly, the odds ratio for osteoporosis was 3.78 (95% CI 1.27-11.26, P < 0.001) in male carriers of haplotype 3 (c.2047A-4037T, n = 20 cases and 12 controls) versus homozygous carriers of haplotype 1 (c.2047G-4037C, n = 42 cases and 61 controls). In conclusion, these data indicate beyond a significant role for environmental factors, an association between LRP5 variants and idiopathic osteoporosis in males, pointing to a role of LRP5 in this disease.

Effects of bisphenol-A (BPA), dibutylphtalate (DBP), benzophenone-2 (BP2), procymidone (Proc), and linurone (Lin) on fat tissue, a variety of hormones and metabolic parameters: a 3 months comparison with effects of estradiol (E2) in ovariectomized (ovx) rats

The endocrine active substances BPA, DBP and BP2 have estrogenic effects in the uterus. Proc and Lin were shown to be antiandrogenic. Whether other estrogen-regulated parameters like lipids, fat metabolism and hormones are also affected by these substances is unknown. We compared the effects of a 3 months lasting administration of these substances with those of E2 on an estrogen-regulated fat depot and on serum TSH, T3, T4, LH, and lipid concentrations. BP2 shared many of the effects of E2 by suppressing LH, cholesterol, LDL, HDL and the size of a small estrogen-regulated fat depot in the lower hindleg. BP2 suppressed T4 but not T3 and TSH. The effects of DBP and BPA were mostly negligible whereas Lin and Proc also reduced the fat depot and serum leptin but increased triglycerides and serum lipids. Serum T3 and T4 concentrations were reduced by Lin and Proc. These data indicate that BP2 has similar, though slightly weaker effects as E2 whereas the effects of Proc and Lin differ from those of E2 on serum lipids and hormones. BP2 can be regarded as an estrogenic endocrine active substance whereas the effects of Lin and Proc appear not to involve estrogen receptors.

Higher bone mineral density in Caucasian, hirsute patients of reproductive age. Positive correlation of testosterone levels with bone mineral density in hirsutism

OBJECTIVE

The mechanisms leading to higher bone mineral density (BMD) in hirsute patients than in healthy controls have seldom been examined. We compared the metabolic, hormonal and bone metabolic parameters in hirsute patients and female controls and correlated BMD and bone metabolic parameters with testosterone, oestradiol and metabolic parameters.

PATIENTS

Fifty-one Caucasian, reproductive-aged, hirsute patients referred to the outpatient clinic of an academic tertiary-care medical centre and 63 healthy, female Caucasian controls matched for season, weight and age.

MEASUREMENTS

BMD (hip, neck, lumbar and total BMD), bone metabolic parameters (osteocalcin, alkaline phosphatase, PTH, ionized calcium, phosphate and 25-hydroxyvitamin D (25OHD)) and endocrine profiles (androgen status, oestradiol and insulin) were evaluated during follicular phase. Oestradiol measurement was repeated during cycle days 8-12.

RESULTS

Lumbar and neck BMD levels were significantly higher in hirsute patients than in controls: (mean +/- SD): lumbar BMD 1.10 +/- 0.12 vs. 1.06 +/- 0.10 g/cm2 and neck BMD 0.91 +/- 0.11 vs. 0.87 +/- 0.12 g/cm2, P < 0.05. Fasting insulin and free testosterone levels were significantly higher in hirsute patients than in controls. Free testosterone correlated positively with neck and hip BMD levels in hirsute patients. During multiple regression analysis, testosterone, oestradiol and waist/hip ratio (WHR) were found to have positive effects on BMD levels independent of body mass index (BMI). 25OHD levels were significantly lower in hirsute patients [42 (13-131)] than in controls [72 (27-196)] nmol/l (geometric mean +/- 2SD), P < 0.001].

CONCLUSION

Hirsute patients demonstrated significantly higher bone mineral density levels than controls, which could be explained by hyperinsulinaemia and higher testosterone levels in hirsute patients compared with controls. The pathogenesis for significantly lower 25-hydroxyvitamin D levels in hirsute patients compared with controls needs to be evaluated in future studies.

Two distinct cytochrome P450 aromatases in the orange-spotted grouper (Epinephelus coioides): cDNA cloning and differential mRNA expression

The cDNA sequences encoding two distinct cytochrome P450 aromatases, namely P450aromB and P450aromA, were isolated from brain and ovary cDNA libraries of the orange-spotted grouper, respectively. The P450aromB cDNA consists of 1892 bp, and the open reading frame (ORF) encodes a putative protein of 506 amino acids. The P450aromA cDNA consists of 1836 bp, and the ORF encodes a putative protein of 518 amino acids. Northern blot analysis revealed a transcript of about 1.9 kb for P450aromB in the brain and kidney, and 2.1 kb for P450aromA in the ovary. The expression of both P450aromB and P450aromA genes in different tissues was further examined using one-step RT-PCR followed by Southern blot analysis. High levels of P450aromB mRNA expression were detected in the olfactory bulb, forebrain, midbrain, hypothalamus, medulla, pituitary, gill filament, gill arch, kidney, muscle, adipose tissue, and blood cells, but low levels in the hindbrain and ovary. High levels of P450aromA mRNA expression were detected in the ovary, pituitary, gill filament, gill arch, and spleen, but low levels in the forebrain, hindbrain, hypothalamus, and blood cells. In addition, the expression of P450arom genes in the orange-spotted grouper of different gonadal stages as induced by 17 alpha-methyltestosterone (MT) was investigated. The mRNA expression of P450aromB in the hypothalamus was highest in the intersexual stage, whereas the mRNA expression of P450aromA in the gonads was highest in the female stage, decreased in the intersexual stage, and lowest in the male stage. Results from current study indicate that P450aromB and P450aromA genes of the orange-spotted grouper have distinct tissue patterns of mRNA expression, and both of them may be involved in the MT-induced sex change.

Osteoporosis: underrated, underdiagnosed and undertreated

Osteoporosis is: (1) Underrated. Currently costs about 7 billion dollars annually in Australia. Has high morbidity and 2-3-fold increase in risk of death after any major osteoporotic fracture. Genetic factors contribute highly to risk, modified by lifestyle and hormonal factors. (2) Underdiagnosed. Bone density is a good predictor of subsequent risk. Anyone with a low-trauma fracture has osteoporosis unless proven otherwise. Every individual with a low trauma fracture should be investigated for exclusion of underlying osteoporosis and considered for effective treatment to reduce future fracture risk. More than 75% of women and about 90% of men with a high likelihood of osteoporosis are not investigated. (3) Undertreated. More than 75% of those affected are not treated. Effective treatments (eg, hormone replacement therapy, selective oestrogen receptor modifiers and bisphosphonates) reduce fracture risk by 30%-60%. Simple measures like vitamin D and calcium supplementation and use of hip protectors can reduce hip fractures, particularly in institutionalised and housebound elderly people

Androgen Replacement Therapy

The major goal of androgen substitution is to replace testosterone at levels as close to physiological levels as is possible. For some androgen-dependent functions testosterone is a pro-hormone, peripherally converted to 5alpha-dihydrotestosterone (DHT) and 17beta-estradiol (E2), of which the levels preferably should be within normal physiological ranges. Furthermore, androgens should have a good safety profile without adverse effects on the prostate, serum lipids, liver or respiratory function, and they must be convenient to use and patient-friendly, with a relative independence from medical services. Natural testosterone is viewed as the best androgen for substitution in hypogonadal men. The reason behind the selection is that testosterone can be converted to DHT and E2, thus developing the full spectrum of testosterone activities in long-term substitution. The mainstays of testosterone substitution are parenteral testosterone esters (testosterone enantate and testosterone cipionate) administered every 2-3 weeks. A major disadvantage is the strongly fluctuating levels of plasma testosterone, which are not in the physiological range at least 50% of the time. Also, the generated plasma E2 is usually supraphysiological. A major improvement is parenteral testosterone undecanoate producing normal plasma levels of testosterone for 12 weeks, with normal plasma levels of DHT and E2 also. Subcutaneous testosterone implants provide the patient, depending on the dose of implants, with normal plasma testosterone for 3-6 months. However, their use is not widespread. Oral testosterone undecanoate dissolved in castor oil bypasses the liver via its lymphatic absorption. At a dosage of 80 mg twice daily, plasma testosterone levels are largely in the normal range, but plasma DHT tends to be elevated. For two decades transdermal testosterone preparations have been available and have an attractive pharmacokinetic profile. Scrotal testosterone patches generate supraphysiological plasma DHT levels, which is not the case with the nonscrotal testosterone patches. Transdermal testosterone gel produces fewer skin irritations than the patches and offers greater flexibility in dosage. Oromucosal testosterone preparations have recently become available. Testosterone replacement is usually of long duration and so patient compliance is of utmost importance. Therefore, the patient must be involved in the selection of type of testosterone preparation. Administration of testosterone to young individuals has almost no adverse effects. With increasing age the risk of adverse effects on the prostate, the cardiovascular system and erythropoiesis increases. Consequently, short-acting testosterone preparations are better suited for aging androgen-deficient men.

Ovarian Dysfunction, Stress, and Disease: A Primate Continuum

Menopause is recognized as a period of increased risk for coronary heart disease (CHD) and osteoporosis. Vulnerability to these conditions is often attributed to the naturally occurring estrogen deficiency characteristic of this part of the life cycle. Premenopausal reductions in endogenous estrogen occasioned by functional ovarian abnormalities or failure are hypothesized to be similarly pathogenic and to accelerate development of CHD and osteoporosis prematurely, thereby increasing the health burden of older women. These functional abnormalities, which occur along a continuum from mild, luteal phase progesterone deficiency to amenorrhea, are relatively common and are often attributed to psychogenic factors (stress, anxiety, depression, or other emotional disturbance), exercise, or energy imbalance. Although numerous investigators have commented on these functional deficits, the abnormalities can be difficult to diagnose and are generally unappreciated for the contribution they may make to postmenopausal disease. Studies in nonhuman primates confirm that these deficits are easily induced by psychological stress and exercise, and that they accelerate the development of cardiovascular disease and perhaps bone loss in the presence of a typical North American diet. However, functional reproductive deficits are also reversible and are thus potentially amenable to environmental or behavioral intervention. Data from both women and nonhuman primates support the hypothesis that functional reproductive deficits are adaptive when triggered appropriately but are detrimental when activated in an environment (e.g., sedentary lifestyle, high-fat diet) permissive to the development of chronic disease.