The relation between cortisol excretion and fractures in healthy older people: results from the MacArthur studies-Mac

Diurnal dynamic range as index of dysregulation of system dynamics. A cortisol examplar using data from the Study of Midlife in the United States

We discuss the importance of including measures of dysregulated system dynamics in the operationalization of allostatic load. The concept of allostatic load, as originally proposed by McEwen and Stellar, included dysregulation not only in the resting state of physiological systems, but also in system dynamics. We describe previous work on cortisol diurnal dynamic range (peak to nadir spread) as an index of the health of the hypothalamic-pituitary-adrenal axis, with compression of dynamic range being a marker of dysregulation. In particular, we review the evidence for a) diurnal dynamic range compression in people from disadvantaged backgrounds, b) cross-sectional association of cortisol diurnal dynamic range compression with dysregulation in other systems' resting states, and c) cross-sectional association of cortisol diurnal dynamic range compression with lower scores on cognitive testing. Then, we present new data from the Study of Midlife in the United States (MIDUS) on longitudinal associations of cortisol dynamic range compression with subsequent cognitive decline and all-cause mortality. Briefly, each standard deviation decrement in cortisol diurnal dynamic range is associated with adjusted mortality hazard ratio of 1.35 (95% confidence interval: 1.19, 1.54). Among those who scored at median or lower in executive functioning at baseline and survive, each standard deviation decrement in cortisol dynamic range is associated with 1% greater decline in executive functioning over a decade (95% confidence interval: 0.4%, 2.0%). We conclude that including measures of system dynamics like diurnal dynamic range in the next generation of allostatic load measurement will likely advance understanding of the cumulative physiological burden of chronic stress and life experiences, and improve the prediction of future health consequences.

Treatment of menopausal symptoms: concomitant modification of cortisol

OBJECTIVES

To evaluate whether change in menopausal symptoms is related to modification of 24-hour urinary cortisol.

METHODS

Sixty-nine postmenopausal women were treated for their menopausal symptoms with either estrogen progestin therapy (0.3 mg conjugate equine estrogens and 1.5 mg medroxyprogesterone acetate; n = 25), phytoestrogens (75 mg isoflavones, twice daily; n = 21) or acupuncture (once a week; n = 23). Baseline and treatment-induced changes of total and subscale scores (vasomotor, depression, anxiety, somatization, sexuality) of the Greene's Climacteric Scale and of 24-hour urinary cortisol were evaluated.

RESULTS

At baseline, 24-hour urinary cortisol was related to Greene's Climacteric Scale score (P < 0.0001). Independent determinants (R2 = 0.319) were the Greene's subscales scores of depression (with a mean difference of 24-h cortisol for score unit expressed as beta coefficient of regression (b) of 4.91, 95% CI 2.14-7.7; P = 0.0007), and of somatization (b 3.04 95% CI 0.69-5.4; P = 0.012). The Greene's Climacteric Scale score (-5.67 ± 6.8; P = 0.0001) and 24-hour cortisol (-23.6 ± 45.7 μg/24 h; P = 0.0001) declined after 3 months of treatment. Changes of 24-hour cortisol values were linearly related to changes of total Greene's Climacteric Scale score with a mean change for unit score (b) of 2.10, 95% CI 0.47-3.73; P = 0.012).

CONCLUSIONS

Present data indicate that greater reduction in menopausal symptoms is associated with a larger decrease in cortisol levels. Possible implication of this finding on the long-term consequences for women's health needs to be explored.

The association between abuse history in childhood and salivary rhythms of cortisol and DHEA in postmenopausal women

A history of child abuse (CA) is associated with morbidity and mortality in adulthood, and one proposed mechanism is dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis. Therefore, we evaluated whether a history of physical and sexual CA was associated with daily rhythms of HPA hormones (cortisol and dehydroepiandrosterone (DHEA)) among postmenopausal women (mean age: 60.6 years). In 2013, 233 participants from the Nurses' Health Study II provided up to 5-timed saliva samples over the course of a day: immediately upon awakening, 45 min, 4 h, and 10 h after waking, and prior to going to sleep. Among these 233 participants, 217 provided ≥4 timed saliva samples. Assessment of physical and sexual CA history occurred in 2001 using the Revised Conflict Tactics Scale. Cumulative CA history was derived by combining reports of physical and sexual abuse prior to age 18. Piecewise linear mixed models compared diurnal rhythms of cortisol and DHEA between participants with none-to-moderate CA (n = 104, reference group) versus high-to-severe CA (n = 113). Models adjusted for characteristics at each saliva collection, health status, sleep quality, medications, and hormone use. Compared to those with none-to-moderate CA, women with high-to-severe CA had different diurnal rhythms in the early and evening hours, including blunted (less steep) early declines in DHEA (% difference (%D) = 10.7, 95 % Confidence Interval (CI) 4.3, 17.5), and steeper late declines in both cortisol and DHEA (cortisol %D = -2.5, 95 % CI -4.8, -0.1, and DHEA %D= -3.9, 95 % CI -6.0, -1.8). In conclusion, high-to-severe abuse history prior to age 18 was more strongly associated with differences in DHEA rather than cortisol, suggesting that early life abuse may be related to dysregulation of stress-response mechanisms later in life.

Association between use of antidepressants or benzodiazepines and the risk of subsequent fracture among those aged 65+ in the Netherlands

This is the first study to examine the association between antidepressant and benzodiazepine use following a MOF and risk of subsequent fracture in those 65+. Using national data, drug use following MOF showed that the 1-year fully adjusted risk of subsequent MOF in those on antidepressants was more than doubled.

INTRODUCTION

We evaluated the association between the use of antidepressants or benzodiazepines and the risk of a subsequent major osteoporotic fracture.

METHODS

A cohort study was performed using the Dutch PHARMO Database Network. Between 2002 and 2011, a total of 4854 patients sustained a first major osteoporotic fracture after the age of 65 years, of which 1766 sustained a hip fracture. Incidence rates and adjusted hazard ratios were calculated using Cox proportional hazards models.

RESULTS

Within 1 year following a major osteoporotic fracture, 15% (95% CI 13.7-15.7) and 31% (95% CI 30.1-32.8) of patients were dispensed an antidepressant or benzodiazepine, respectively. Current use of antidepressants in the first year following a major osteoporotic fracture was associated with subsequent fracture (adjusted HR 2.17 (95% CI 1.37-3.43)). Recent and past use of antidepressants were also associated with an increased risk of subsequent fracture. When the complete follow-up period was included, only the current use of antidepressants was associated with subsequent fracture following a major osteoporotic fracture (adjusted HR 1.48; 95% CI 1.06-2.06). Current benzodiazepine use was not associated with an increased risk of fracture within 1 year following a major osteoporotic fracture (adjusted HR 1.18; 95% CI 0.76-1.81) or during the complete follow-up period (adjusted HR 1.18; 95% CI 0.90-1.55).

CONCLUSION

This study provides evidence that antidepressants should be used with caution following a major osteoporotic fracture. It provides needed insights that can be used to inform clinicians when assessing subsequent fracture risk in patients.

Glucocorticoids and Bone: Consequences of Endogenous and Exogenous Excess and Replacement Therapy

Osteoporosis associated with long-term glucocorticoid therapy remains a common and serious bone disease. Additionally, in recent years it has become clear that more subtle states of endogenous glucocorticoid excess may have a major impact on bone health. Adverse effects can be seen with mild systemic glucocorticoid excess, but there is also evidence of tissue-specific regulation of glucocorticoid action within bone as a mechanism of disease. This review article examines (1) the role of endogenous glucocorticoids in normal bone physiology, (2) the skeletal effects of endogenous glucocorticoid excess in the context of endocrine conditions such as Cushing disease/syndrome and autonomous cortisol secretion (subclinical Cushing syndrome), and (3) the actions of therapeutic (exogenous) glucocorticoids on bone. We review the extent to which the effect of glucocorticoids on bone is influenced by variations in tissue metabolizing enzymes and glucocorticoid receptor expression and sensitivity. We consider how the effects of therapeutic glucocorticoids on bone are complicated by the effects of the underlying inflammatory disease being treated. We also examine the impact that glucocorticoid replacement regimens have on bone in the context of primary and secondary adrenal insufficiency. We conclude that even subtle excess of endogenous or moderate doses of therapeutic glucocorticoids are detrimental to bone. However, in patients with inflammatory disorders there is a complex interplay between glucocorticoid treatment and underlying inflammation, with the underlying condition frequently representing the major component underpinning bone damage.

Testosterone supplementation, glucocorticoid milieu and bone homeostasis in the ageing male

Male ageing is entwined with a continuous fall in free testosterone levels, which contributes to the pathogenesis of bone loss. Glucocorticoid excess, either dependent on the ageing process or iatrogenically induced, was found to additionally impair the bone structure and metabolism. Cautious testosterone supplementation in this respect may positively affect the glucocorticoid milieu and bone homeostasis, while testosterone-induced changes in the glucocorticoid output could serve as a determinant of bone-related therapeutic outcome. Namely, bone mineral content/density, the parameters of trabecular bone structure as well as bone strength are enhanced, serum calcitonin levels tend to increase, while serum osteocalcin, serum parathyroid hormone and urinary calcium decrease, all upon testosterone administration to the ageing male. In parallel, testosterone application decreases glucocorticoid secretion in the animal models of male ageing, while clinical data in this field are still inconsistent. Importantly, a physiological link exists between testosterone-induced changes in glucocorticoid levels and the tendency of bone status improvement in the ageing male. We believe that the assessment of circulating adrenocorticotropic hormone concentrations together with glucocorticoid levels, reflecting the hypothalamic-pituitary-adrenal axis feedback loop operativeness during testosterone supplementation, represents a well-balanced bone-related therapeutic update.

The role of adaptive bone formation in the etiology of stress fracture

Stress fractures are common injuries with load-bearing activities. Stress fractures have been reported in the scientific literature for over a century; however, the etiology continues to be investigated with important distinctions made between the contributions of the tissue-level processes of bone remodeling and modeling. In response to novel repetitive loading, increased bone remodeling may serve to replace fatigue-damaged bone while at the same time creating temporary porosity. Much attention has been given to the role of remodeling in the etiology of stress fracture; however, the role of bone modeling has received less attention. Modest increases in modeling, via bone formation on the periosteal surface of long bones in response to mechanical loading, greatly increases the fatigue resistance of bone. Thus, enhancing this adaptive bone formation is a promising target for stress fracture prevention, and a focus on adaptive bone formation may reveal novel risk factors for stress fracture.

Higher diet-dependent renal acid load associates with higher glucocorticoid secretion and potentially bioactive free glucocorticoids in healthy children

Metabolic acidosis induces elevated glucocorticoid (GC) levels. However, the influence of less strong daily acid loads on GCs is largely unexplored. To investigate this, we studied whether higher acid loads in children, fully within the normal range of habitual diets, associate with endogenous GCs. In a specific quasi-experimental design, we examined 200 6- to 10-year-old healthy participants of the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study equally divided to either high or low 24-hour renal net acid excretion. Major urinary GC metabolites were analyzed by gas chromatography-mass spectrometry to assess daily adrenal GC secretion and metabolites of tissue cortisol catabolism (6β-hydroxycortisol and 20α-dihydrocortisol). Liquid chromatography-mass spectrometry was used to quantify urinary free cortisol and cortisone. After confounder adjustment, significant positive associations were unmasked for urinary potential renal acid load and net acid excretion with adrenal GC secretion, free cortisone, free cortisone plus cortisol, 6β-hydroxycortisol, and 20α-dihydrocortisol. An inverse association emerged for an enzymatic marker (5β-reductase) of irreversible GC inactivation. Our data suggest that existing moderate elevations in diet-dependent acid loads suffice to raise GCs and affect cortisol metabolism. Thus, potential detrimental effects of high acid loading appear to be mediated, in part, by increased GC activity via increased GC secretion and/or reduced GC inactivation. Higher cortisone levels, directly available for intracrine activation to cortisol may play a special role.

Associations between hypothalamic-pituitary-adrenal axis function and peak bone mass at 20years of age in a birth cohort

In older adults, high-normal circulating cortisol levels are associated with lower bone mass, but relationships between hypothalamic-pituitary-adrenal axis function and peak bone mass in young adults have not been examined. We studied 411 male and 390 female participants in the Western Australia Pregnancy Cohort (Raine) Study. At 18years of age, participants underwent a Trier Social Stress Test (TSST) with measurement of plasma and salivary cortisol at baseline and at multiple time points after stress. Cortisol responses were classified as anticipatory responder (significant fall in cortisol during the test), reactive responder (significant increase) or non-responder. At 20years, total body bone mineral content (BMC) and density (BMD) were measured by DXA. In males, after adjustment for weight, height (for BMC and bone area only), alcohol and smoking, there was a significant inverse relationship between both plasma and salivary cortisol measured at baseline in the TSST and each of BMC and BMD, such that each additional 10% of salivary cortisol was associated with reductions of 6.9g (95% CI -11.7, -2.2) in BMC, and 1.8mg/cm(2) (95% CI -3.3, -0.4) in BMD. Males classified as anticipatory responders in the TSST had 3.2% lower BMC (adjusted mean±SE: 3131±28 vs. 3233±18g, P=0.006) and 2.5% lower BMD (1108±9 vs. 1136±6mg/cm(2), P=0.022) than reactive responders. In females, there were no significant relationships between baseline cortisol or TSST responses and BMC or BMD in covariate-adjusted analyses. We conclude that in young males (but not females), higher circulating cortisol at the baseline of the stress test and an anticipatory responder pattern on the TSST are associated with lower total body bone mass.

The relationship between weight change and risk of hip fracture: meta-analysis of prospective studies

The relationship between weight change and risk of hip fracture is still controversial. We searched PubMed and Embase for studies on weight change and risk of hip fracture. Eight prospective studies were included. The weight loss studies included 85592 participants with 1374 hip fractures, and the weight gain studies included 80768 participants with 732 hip fractures. Weight loss is more likely a risk factor of hip fracture, with an adjusted RR (Relative Risk) (95% CI) of 1.84 (1.45, 2.33). In contrast, weight gain can decrease the risk of hip fracture, with an adjusted RR (95% CI) of 0.73 (0.61, 0.89). Dose-response meta-analysis shows that the risk of hip fracture is an ascending curve, with an increase of weight loss above the line of RR = 1; this trend is consistent with the results of forest plots that examine weight loss and hip fracture. For weight gain and risk of hip fracture, the descending curve below the line of RR = 1; this trend is consistent with the results of forest plots that examine weight gain and hip fracture. Our meta-analysis suggests that weight loss may be a risk factor for hip fracture and that weight gain may be a protective factor for hip fracture.

The association between urinary cortisol excretion and cardiovascular risk factors, bone status and quality of life in the population

OBJECTIVE

Patients with glucocorticoid excess have increased cardiovascular risk, decreased bone mineral density and impaired quality of life (QoL). The aim of this study was to evaluate the association between urinary cortisol excretion and cardiovascular risk factors, bone status and QoL in the population. We hypothesized that higher cortisol excretion was associated with adverse cardiovascular risk profile, worse skeletal health and QoL.

DESIGN, PATIENTS AND METHODS

This was a cross-sectional study including a population sample (n=348), aged 38-77years. The mean age in women was 64.0±8.5years (n=276) and 60.3±10.2years in men (n=72). The metabolic syndrome, body composition measured with bioimpedance, calcaneal quantitative ultrasound, fractures and QoL evaluated with the Nottingham Health Profile, Psychological General Well-Being (PGWB) and the Short Form 36 (SF-36) were studied. Urinary free cortisol (UFC) was measured using radioimmunoassay.

RESULTS

UFC was higher in men (230±120nmol/L) compared to women (153±71; P<0.001) and decreased with increasing age (P<0.001). In a regression analysis, after adjustment for gender, age and body mass index, higher UFC was associated with higher fat-free mass (P<0.01), favourable calcaneal bone measurements (P<0.05), better general health measured with PGWB (P<0.01) and SF-36 (P=0.001) and tended to be negatively associated with the metabolic syndrome (P=0.07).

CONCLUSION

In contrast to our hypothesis, UFC in the upper physiological range was associated with a favourable cardiovascular risk profile, bone measures and QoL.

Hypothalamic-pituitary-adrenal (HPA) axis and aging

Human aging is associated with increasing frailty and morbidity which can result in significant disability. Dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis may contribute to aging-related diseases like depression, cognitive deficits, and Alzheimer's disease in some older individuals. In addition to neuro-cognitive dysfunction, it has also been associated with declining physical performance possibly due to sarcopenia. This article reviews the pathophysiology of HPA dysfunction with respect to increased basal adrenocorticotropic hormone (ACTH) and cortisol secretion, decreased glucocorticoid (GC) negative feedback at the level of the paraventricular nucleus (PVN) of the hypothalamus, hippocampus (HC), and prefrontal cortex (PFC), and flattening of diurnal pattern of cortisol release. It is possible that the increased cortisol secretion is secondary to peripheral conversion from cortisone. There is a decline in pregnolone secretion and C-19 steroids (DHEA) with aging. There is a small decrease in aldosterone with aging, but a subset of the older population have a genetic predisposition to develop hyperaldosteronism due to the increased ACTH stimulation. The understanding of the HPA axis and aging remains a complex area with conflicting studies leading to controversial interpretations.

Higher glucocorticoid secretion in the physiological range is associated with lower bone strength at the proximal radius in healthy children: importance of protein intake adjustment

Whether higher production of glucocorticoids (GCs) within the physiological range may already be affecting bone status in healthy children is unknown. Because dietary protein intake affects both bone and GCs, we examined the association of urinary measures of glucocorticoid status and cortical bone in healthy non-obese children, after particularly controlling for protein intake. Proximal forearm bone parameters were measured by peripheral quantitative computed tomography (pQCT). Subjects studied (n = 175, 87 males, aged 6 to 18 years) had two 24-hour urine samples collected: the first sample at 1 year before bone measurement, and the second sample at the time of bone measurement. Major urinary GC metabolites were measured by mass spectrometry and summed to assess daily adrenal GC secretion (∑C21). Urinary free cortisol (UFF) and cortisone (UFE) were summed to assess potentially bioactive free GCs (UFF + UFE). After controlling for several covariates and especially urinary nitrogen (the biomarker of protein intake) cortisol secretion ∑C21 was inversely associated with all analyzed pQCT measures of bone quality. ∑C21 also predicted a higher endosteal and lower periosteal circumference, explaining both a smaller cortical area and (together with lower BMD) a lower strength-strain-index (SSI). UFF + UFE, UFE itself, and a urinary metabolite-estimate of 11beta-hydroxysteroid dehydrogenase type1 (11beta-HSD1) activity showed corresponding reciprocal associations (p < 0.05) with BMD and bone mineral content, but not with SSI and bone geometry variables. In conclusion, higher GC levels, even within the physiological range, appear to exert negative influences on bone modeling and remodeling already during growth. Our physiological data also suggest a relevant role of cortisone as the direct source for intracrine-generated cortisol by bone cell 11beta-HSD1.

Bone formation is suppressed with multi-stressor military training

PURPOSE

To determine the effects of US Army Ranger Training, an 8-week, physically demanding program (energy expenditure of 2,500-4,500 kcal/day) with energy restriction (deficit of 1,000-4,000 kcal/day) and sleep deprivation (<4 h sleep/night) on bone metabolism.

METHODS

Blood was collected from 22 men (age 24 ± 4 years) before and after training. Follow-up measurements were made in a subset of 8 subjects between 2 and 6 weeks after training. Serum was analyzed for bone formation biomarkers [bone alkaline phosphatase (BAP) and osteocalcin (OCN)], bone resorption biomarkers [C-telopeptide cross-links of type I collagen (CTX) and tartrate-resistant acid phosphatase (TRAP5b)], calcium, parathyroid hormone (PTH), and vitamin D 25(OH)D increased significantly by 37.3 ± 45.2 % with training [corrected]. A repeated-measures ANOVA with time as the only factor was used to analyze data on the subset of 8 subjects who completed follow-up data collection.

RESULTS

BAP and OCN significantly decreased by 22.8 ± 15.5% (pre 41.9 ± 10.1; post 31.7 ± 7.8 ng/ml) and 21.0 ± 23.3% (pre 15.0 ± 3.5; post 11.3 ± 2.1 ng/ml), respectively, with training, suggesting suppressed bone formation. OCN returned to baseline, while BAP remained suppressed 2-6 weeks post-training. TRAP5b significantly increased by 57.5 ± 51.6% (pre 3.0 ± 0.9; post 4.6 ± 1.4 ng/ml) from pre- to post-training, suggesting increased bone resorption, and returned to baseline 2-6 weeks post-training. PTH Increased significantly by 37.3 ± 45.2% with training. No changes in CTX, calcium, or PTH were detected.

CONCLUSIONS

These data indicate that multi-stressor military training results in increased bone resorption and suppressed bone formation, with recovery of bone metabolism 2-6 weeks after completion of training.

Endogenous Glucocorticoids and Bone

While the adverse effects of glucocorticoids on bone are well described, positive effects of glucocorticoids on the differentiation of osteoblasts are also observed. These paradoxical effects of glucocorticoids are dose dependent. At both physiologicaland supraphysiological levels of glucocorticoids, osteoblasts and osteocytes are the major glucocorticoid target cells. However, the response of the osteoblasts to each of these is quite distinct. At physiology levels, glucocorticoids direct mesenchymal progenitor cells to differentiate towards osteoblasts and thus increase bone formation in a positive way. In contrast with ageing, the excess production of glucocorticoids, at both systemic and intracellular levels, appear to impact on osteoblast and osteocytes in a negative way in a similar fashion to that seen with therapeutic glucocorticoids. This review will focus on therole of glucocorticoids in normal bone physiology, with particular emphasis on the mechanism by which endogenous glucocorticoids impact on bone and its constituent cells.

A pilot randomized, single-blind, placebo-controlled trial of traditional acupuncture for vasomotor symptoms and mechanistic pathways of menopause

OBJECTIVE

The aim of this study was to conduct a pilot study for the feasibility of planning a definitive clinical trial comparing traditional acupuncture (TA) with sham acupuncture (SA) and waiting control (WC) on menopause-related vasomotor symptoms (VMS), quality of life, and the hypothalamic-pituitary-adrenal axis in perimenopausal and postmenopausal women.

METHODS

Thirty-three perimenopausal and postmenopausal women with at least seven VMS daily were randomized to TA, SA, or WC. The TA and SA groups were given three treatments per week for 12 weeks. Outcomes included the number and severity of VMS, Menopause-Specific Quality of Life Questionnaire, Beck Depression Inventory, Spielberg State-Trait Anxiety Instrument, Pittsburgh Quality Sleep Index, 24-hour urine cortisol and metabolites, and adrenocorticotropic hormone stimulation testing.

RESULTS

Both the TA and SA groups demonstrated improved VMS trends compared with the WC group (Δ -3.5 ± 3.00 vs -4.1 ± 3.79 vs -1.2 ± 2.4, respectively; P = 20) and significantly improved Menopause-Specific Quality of Life Questionnaire vasomotor scores (Δ -1.5 ± 2.02 vs -1.8 ± 1.52 vs -0.3 ± 0.64, respectively; P = 0.04). There were no psychosocial group differences. Exit 24-hour urinary measures were lower in the TA versus the SA or WC group in total cortisol metabolites (4,658.9 ± 1,670.9 vs 7,735.8 ± 3,747.9 vs 5,166.0 ± 2,234.5, P = 0.03; respectively) and dehydroepiandrosterone (41.4 ± 27.46, 161.2 ± 222.77, and 252.4 ± 385.40, respectively; P = 0.05). The response data on adrenocorticotropic hormone stimulation cortisol also trended in the hypothesized direction (P = 0.17).

CONCLUSIONS

Both TA and SA reduce VMS frequency and severity and improve VMS-related quality of life compared with WC; however, TA alone may impact the hypothalamic-pituitary-adrenal axis. This association is viewed as preliminary and hypothesis generating and should be explored in a large clinical trial.

The relationship between 24-h urinary cortisol and bone in healthy young women

BACKGROUND

Cortisol within the normal range has been associated with reduced bone density in the elderly, but little is known about this relationship in healthy young women.

PURPOSE

The purpose of this study is to assess whether 24-h urinary free cortisol excretion (UFC) is related to bone density in 132 healthy, non-obese, regularly menstruating women, aged 19-35.

METHOD

Participants completed questionnaires (food frequency, demographics, physical activity, dietary restraint, perceived stress, and daily stress) and a 24-h urine collection. UFC was determined by high-throughput liquid chromatography and tandem mass spectrometry. Anthropometrics were completed and a dual energy X-ray absorptiometry scan measured areal bone mineral density (aBMD, g/cm(2)) and bone mineral content (BMC, g) at the lumbar spine (L1-4), hip, and total body (TB) as well as total body lean (LBM) and fat mass.

RESULTS

aBMD and BMC were significantly positively associated with height, LBM, physical activity, calcium intake, and duration of previous oral contraceptive use (except L1-4) and negatively with perceived stress. UFC was not correlated with any measured variables except urine volume (r = 0.17, p = 0.046). After adjusting for urine volume, height, LBM, ethnicity, and prior oral contraceptive use, UFC was significantly inversely associated with TB BMC (r = -0.30, p < 0.001) and aBMD (r = -0.27, p = 0.003), L1-4 aBMD (r = -0.19, p = 0.035) and BMC (r = -0.18, p = 0.049), and hip BMC (r = -0.23, p = 0.011). Further adjustment for sport activity, calcium intake and perceived stress did not change these relationships meaningfully except that L1-4 became nonsignificant (p < 0.07).

CONCLUSION

Cortisol within the normal range appears to have a minor negative influence on bone density in healthy young women.

Adiponectin and negative mood in healthy premenopausal and postmenopausal women

Negative mood and stress are associated with cardiovascular and metabolic disease. There are likely many physiological mechanisms underlying the poor health outcomes. The relationship of psychological states (negative mood, life stress, and stress-responsive hormones) and adiponectin, an adipokine that promotes insulin sensitivity, was investigated in two separate studies. The two groups of participants included 52 healthy, premenopausal women, and 63 postmenopausal women with a range of stress levels. The relationship between adiponectin and psychological state (perceived stress and negative mood) was examined cross-sectionally in both groups of participants, but also prospectively (1 year later) in the group of postmenopausal women. In premenopausal women, negative mood and nocturnal urinary epinephrine were significantly related to adiponectin, independent of BMI. In postmenopausal women, negative mood was not associated with adiponectin cross-sectionally, but negative mood was a significant predictor for lower levels of adiponectin 1 year later, independent of initial adiponectin concentrations and changes in body mass index. Lastly, having a depressive disorder was related to lower adiponectin. As adiponectin levels are associated with insulin resistance, obesity, and diabetes mellitus, these findings suggest there may be an adiponectin-mediated pathway explaining in part how negative mood affects metabolic health. Mechanistic studies are needed to explore this potential relationship further.

Effects of testosterone administration on nocturnal cortisol secretion in healthy older men

In animal studies, testosterone decreases, whereas estrogen increases, cortisol production. In one clinical study, short-term testosterone replacement attenuated corticotrophin-releasing hormone-stimulated cortisol secretion during leuprolide-induced hypogonadism in young men. The effects of longer term testosterone treatment on spontaneous cortisol secretion in younger or older men are unknown. In a randomized, double-masked placebo-controlled study, we assessed the effects of testosterone supplementation (100 mg intramuscular every 2 week) for 26 weeks on nocturnal cortisol secretory dynamics in healthy older men. Testosterone administration increased early morning serum concentrations of free testosterone by 34%, decreased sex hormone-binding globulin by 20%, and did not alter early morning concentrations of cortisol-binding globulin or cortisol compared with placebo treatment. Testosterone did not significantly alter nocturnal mean and integrated cortisol concentrations, cortisol burst frequency, mass/burst, basal secretion, pulsatile cortisol production rate, pattern regularity, or approximate entropy. We conclude that low-dose testosterone supplementation for 26 weeks does not affect spontaneous nocturnal cortisol secretion in healthy older men.

Adrenal gland and bone

The adrenal gland synthesizes steroid hormones from the adrenal cortex and catecholamines from the adrenal medulla. Both cortisol and adrenal androgens can have powerful effects on bone. The overproduction of cortisol in Cushing's disease leads to a dramatic reduction in bone density and an increase risk of fracture. Overproduction of adrenal androgens in congenital adrenal hyperplasia (CAH) leads to marked changes in bone growth and development with early growth acceleration but ultimately a significant reduction in final adult height. The role of more physiological levels of glucocorticoids and androgens on bone metabolism is less clear. Cortisol levels measured in elderly individuals show a weak correlation with measures of bone density and change in bone density over time with a high cortisol level associated with lower bone density and more rapid bone loss. Cortisol levels and the dynamics of cortisol secretion change with age which could also explain some age related changes in bone physiology. It is also now clear that adrenal steroids can be metabolized within bone tissue itself. Local synthesis of cortisol within bone from its inactive precursor cortisone has been demonstrated and the amount of cortisol produced within osteoblasts appears to increase with age. With regard to adrenal androgens there is a dramatic reduction in levels with aging and several studies have examined the impact that restoration of these levels back to those seen in younger individuals has on bone health. Most of these studies show small positive effects in women, not men, but the skeletal sites where benefits are seen varies from study to study.

Depression and osteoporosis: a research synthesis with meta-analysis

Major depressive disorder has been associated with low bone mineral density. The strength of this association, however, varies greatly among studies; the direction of the causative link is still controversial, and the etiology remains unclear. We aimed to confirm this association, assess its magnitude and estimate its clinical relevancy. A total of 535 articles were initially identified and the research synthesis was based on 33 qualified articles. Of these, 25 articles (or 76%) showed an inverse relationship between major depression or minor depression or depressive symptoms and bone mineral density or bone turnover. Meta-analysis could be performed on 20 of the initially selected 33 articles. Standardized weighted differences in mean AP spine, total femur and femoral neck bone mineral density, each from at least 10 studies, were computed in g/cm (2) and transformed into percent differences. At each site, bone mass was lower in subjects with depression as compared to controls: AP spine bone mineral density was 4.73% lower (95% CI -7.28% to -2.19%, p<0.0001; n=16 studies), total femur bone mineral density was 3.53% lower (95% CI -5.66% to -1.41%, p<0.001; n=13 studies), and femoral neck bone mineral density was 7.32% lower (95% CI -10.67% to -3.96%; p<0.0005; n=8 studies). In conclusion, major depressive disorder was associated with lower bone mineral density at the AP spine, femoral neck, and total femur. The deficits in bone mineral density in subjects with depression are of clinical significance and likely to increase fracture risk over the lifetime of these subjects.

The elderly as a sensitive population in environmental exposures: making the case

The US population is aging. CDC has estimated that 20% of all Americans will be 65 or older by the year 2030. As a part of the aging process, the body gradually deteriorates and physiologic and metabolic limitations arise. Changes that occur in organ anatomy and function present challenges for dealing with environmental stressors of all kinds, ranging from temperature regulation to drug metabolism and excretion. The elderly are not just older adults, but rather are individuals with unique challenges and different medical needs than younger adults. The ability of the body to respond to physiological challenge presented by environmental chemicals is dependent upon the health of the organ systems that eliminate those substances from the body. Any compromise in the function of those organ systems may result in a decrease in the body's ability to protect itself from the adverse effects of xenobiotics. To investigate this issue, we performed an organ system-by-organ system review of the effects of human aging and the implications for such aging on susceptibility to drugs and xenobiotics. Birnbaum (1991) reported almost 20 years ago that it was clear that the pharmacokinetic behavior of environmental chemicals is, in many cases, altered during aging. Yet, to date, there is a paucity of data regarding recorded effects of environmental chemicals on elderly individuals. As a result, we have to rely on what is known about the effects of aging and the existing data regarding the metabolism, excretion, and adverse effects of prescription medications in that population to determine whether the elderly might be at greater risk when exposed to environmental substances. With increasing life expectancy, more and more people will confront the problems associated with advancing years. Moreover, although proper diet and exercise may lessen the immediate severity of some aspects of aging, the process will continue to gradually degrade the ability to cope with a variety of injuries and diseases. Thus, the adverse effects of long-term, low-level exposure to environmental substances will have a longer time to be manifested in a physiologically weakened elderly population. When such exposures are coupled with concurrent exposure to prescription medications, the effects could be devastating. Public health officials must be knowledgeable about the sensitivity of the growing elderly population, and ensure that the use of health guidance values (HGVs) for environmental contaminants and other substances give consideration to this physiologically compromised segment of the population.

Cortisol levels during the menopausal transition and early postmenopause: observations from the Seattle Midlife Women's Health Study

OBJECTIVE

Cortisol levels rise among some women during the late stage of the menopausal transition (MT), but we know little about changes in cortisol levels in relation to menopause-related factors (MT stage, urinary estrone glucuronide [E1G], testosterone, follicle-stimulating hormone [FSH]), stress-related factors (epinephrine, norepinephrine, and perceived stress), symptoms (hot flashes, mood, memory, and sleep), social factors (income adequacy, role burden, social support, employment, parenting, and history of sexual abuse), and health-related factors (depressed mood, perceived health, physical appraisal, body mass index, and smoking). The aim of the study was to examine the influence of menopause-related factors, stress-related factors, symptoms, social factors, and health-related factors on cortisol levels during the MT.

METHODS

Participants were a subset of Seattle Midlife Women's Health Study who provided data during the late reproductive, early and late MT stages, or early postmenopause and who were not using hormone therapy or corticosteroids (N = 132 women, up to 5,218 observations). Data provided included menstrual calendars for staging the MT, annual health reports, health diaries, and overnight urine specimens (assayed for cortisol, catecholamines, E1G, and FSH) between 1990 and 2005 were included. Perceived stress, symptoms, and health behaviors were assessed in a health diary. Health-related and social factors were assessed in an annual health update. Multilevel modeling was used to test the effects of menopause-related and other factors on overnight cortisol levels.

RESULTS

When tested with age as a measure of time, menopause-related covariates, including E1G, FSH, and testosterone, were associated with significant increases in overnight cortisol levels (P < 0.0001). Likewise, epinephrine and norepinephrine were each associated significantly with overnight cortisol levels (P < 0.0001). In multivariate analyses, E1G, FSH, and testosterone constituted the best set of predictors.

CONCLUSIONS

Overnight cortisol levels during the MT were associated with E1G, testosterone, and FSH levels. In addition, they were significantly and positively associated with epinephrine and norepinephrine. MT stage, symptoms, and social, stress-related, and health-related factors had little relationship to overnight cortisol levels when other biological indicators were considered.

Increased urinary cortisol levels during the menopausal transition

OBJECTIVE

To determine whether cortisol levels change prospectively during the menopausal transition (MT); whether these changes are associated with changes in the hypothalamic-pituitary-ovarian axis (follicle-stimulating hormone [FSH] and estrone glucuronide [E1G]), stressors, or menopause symptoms; and whether women who experienced a rise in cortisol levels during the transition had behavioral practices, stressors, vasomotor symptoms, or mood or sleep disturbances that affected hypothalamic-pituitary-adrenal axis function.

DESIGN

One hundred sixty-nine women in the middle or late MT or early postmenopause stages provided monthly urine specimens for cortisol, FSH, and E1G, and rated symptoms and stress levels as part of a longitudinal study of the MT. Of these women, 91 completed a transition to the next MT stage: from early to middle (n = 30), middle to late (n = 39), or late to postmenopause (n = 22) and were eligible for inclusion in the analyses.

RESULTS

Cortisol increased from 7 to 12 months before the late MT stage to 7 to 12 months after onset of the late MT stage. There were no differences before and after the middle MT stage or the final menstrual period. Women with increased cortisol (>10 ng/mg creatinine) during the late MT stage had more severe vasomotor symptoms than those without changes, but did not differ in terms of age, body mass index, levels of FSH or E1G, health practices, exercise, mood, sleep, cognition, or stress levels.

CONCLUSIONS

Cortisol levels rise with age, but have not been linked to stages of the MT. Increased cortisol levels during the late MT stage, when menstrual irregularities are greatest, suggests increases in adrenal androgens and intraabdominal fat with menopause, and may influence risk of cardiovascular disease, vasomotor symptoms, mood, cognition, and bone loss.

Depression and osteoporosis: epidemiology and potential mediating pathways

INTRODUCTION

There have been numerous studies examining the association between depression and bone mineral density (BMD), but the underlying nature of this relationship remains unclear. Independent of this association, there is a growing body of evidence that depression impacts the risk for fracture in older adults. This article reviews the current epidemiological evidence regarding comorbidity of depression, low bone mineral density, and fracture.

METHODS

A review of the literature on depression, depressive symptoms, low BMD, osteoporosis, and fracture using electronic databases.

RESULTS

We reviewed 20 studies of the association between depression and BMD and five reports of the relationship between depression and fractures. Potential mediating mechanisms (both physiological and behavioral) are discussed, as well as potential confounding influences (e.g., medication use).

CONCLUSIONS

Most studies support the finding that depression is associated with increased risk for both low BMD and fractures, but variation in study design, sample composition, and exposure measurement make comparisons across studies difficult. Researchers should be aware of potential confounders, such as medication use, that may influence results. Future research should focus on identifying mediating pathways and targets for intervention in the relationships between depression, low BMD, and fracture.

Biomarkers related to aging in human populations

Biomarkers are increasingly employed in empirical studies of human populations to understand physiological processes that change with age, diseases whose onset appears linked to age, and the aging process itself. In this chapter, we describe some of the most commonly used biomarkers in population aging research, including their collection, associations with other markers, and relationships to health outcomes. We discuss biomarkers of the cardiovascular system, metabolic processes, inflammation, activity in the hypothalamic-pituitary axis (HPA) and sympathetic nervous system (SNS), and organ functioning (including kidney, lung, and heart). In addition, we note that markers of functioning of the central nervous system and genetic markers are now becoming part of population measurement. Where possible, we detail interrelationships between these markers by providing correlations between high risk levels of each marker from three population-based surveys: the National Health and Nutrition Examination Survey (NHANES) III, NHANES 1999-2002, and the MacArthur Study of Successful Aging. NHANES III is used instead of NHANES 1999-2002 when specific markers of interest are available only in NHANES III and when we examine the relationship of biomarkers to mortality which is only known for NHANES III. We also describe summary measures combining biomarkers across systems. Finally, we examine associations between individual markers and mortality and provide information about biomarkers of growing interest for future research in population aging and health.

The endocrine system and ageing

Complex changes occur within the endocrine system of ageing individuals. This article explores the changes that occur in the metabolism and production of various hormones and discusses the resulting clinical consequences. As individuals age there is a decline in the peripheral levels of oestrogen and testosterone, with an increase in luteinizing hormone, follicle-stimulating hormone and sex hormone-binding globulin. Additionally there is a decline in serum concentrations of growth hormone, insulin-like growth factor-I and dehydroepiandrosterone and its sulphate-bound form. Even though there are complex changes within the hypothalmo-pituitary-adrenal/thyroid axis, there is minimal change in adrenal and thyroid function with ageing. The clinical significance of these deficiencies with age are variable and include reduced protein synthesis, decrease in lean body mass and bone mass, increased fat mass, insulin resistance, higher cardiovascular disease risk, increase in vasomotor symptoms, fatigue, depression, anaemia, poor libido, erectile deficiency and a decline in immune function. For each endocrine system, studies have been carried out in an attempt to reverse the effects of ageing by altering the serum hormonal levels of older individuals. However, the real benefits of hormonal treatment in older individuals are still being evaluated.

High Cognitive Dietary Restraint Is Associated With Increased Cortisol Excretion in Postmenopausal Women

BACKGROUND

Cognitive dietary restraint (perceived ongoing effort to limit dietary intake to manage body weight) is common in women at all life stages. In young women, high dietary restraint has been associated with both increased excretion of cortisol (a stress hormone) and reduced bone mass. Whether this occurs in older women is unknown and is reported here for the first time.

METHODS

Postmenopausal women (49-75 years old) with high (n = 41) or low (n = 37) dietary restraint were compared to examine differences in urinary cortisol excretion, body composition assessed by dual-energy x-ray absorptiometry (bone mineral density, % body fat), dietary intake, anthropometrics, current exercise, and perceived stress.

RESULTS

Women with high or low dietary restraint did not differ in age, body mass index, waist-to-hip ratio, energy intake, perceived stress, current exercise, or measures of body composition. However, urinary cortisol excretion was higher in the high restraint group (248.2 +/- 61.7 nmol/d vs 204.3 +/- 66.1 nmol/d; p =.01). Multiple regression analysis indicated that restraint group (high or low) independently predicted 7.6% of the variance in cortisol excretion.

CONCLUSIONS

Postmenopausal women with high dietary restraint excrete more cortisol than do those with low restraint, suggesting that dietary restraint may be a source of stress. Although this was not associated with negative health effects in this sample, further investigation is warranted.

Cortisol secretion and rate of bone loss in a population-based cohort of elderly men and women

Although excessive glucocorticoids are a well-recognized cause of osteoporosis, little is known about the role of endogenous glucocorticoids in determining skeletal mass. We have performed a detailed study of the hypothalamic-pituitary-adrenal (HPA) axis to explore the relationships between cortisol secretion and adult bone mass in 151 healthy men and 96 healthy women aged 61 to 73 years. At baseline and 4-year follow-up, bone mineral density (BMD) was measured by dual energy X-ray absorptiometry (DXA) at the lumbar spine and proximal femur; a lifestyle questionnaire was completed; and height, weight, and waist and hip circumferences were measured. At follow-up subjects underwent a very low-dose (0.25 mg) dexamethasone suppression test, a low-dose (1 microg) short synacthen test, and a 24-hour urine collection for measurement of cortisol and its metabolites. In men, elevated peak plasma cortisol was associated with accelerated loss of mineral density in the lumbar spine (r = 0.16, P = 0.05). This relationship remained significant after adjustment for testosterone, estradiol, 25-hydroxyvitamin D, and parathyroid hormone levels (r = 0.22, P = 0.01) and after additional adjustment for age, (BM), activity, cigarette and alcohol consumption, and Kellgren/Lawrence score (r = 0.19, P = 0.03). In contrast in women, elevated peak plasma cortisol was associated with lower baseline BMD at the femoral neck (r = -0.23, P = 0.03) and greater femoral neck loss rate (r = 0.24, P = 0.02). There was no association between plasma cortisol concentrations after dexamethasone or urinary total cortisol metabolite excretion and bone density or bone loss rate at any site. These data provide evidence that circulating endogenous glucocorticoids influence the rate of involutional bone loss in healthy individuals.

Long-term mental distress, bone mineral density and non-vertebral fractures. The Tromsø Study

The purpose of this study was to examine, prospectively, the risk of non-vertebral fractures and low bone mineral density in a population-based cohort with respect to indicators of subjective mental distress. In 1979-1980 all males born 1925-1959 and all females born 1930-1959 living in Tromsø were invited (21,441; response rate, 78%). The same individuals were invited to the subsequent studies in 1986-1987 and 1994-1995 (74% attended the first two, and 71% attended all three surveys). Non-vertebral fractures were registered by linkage to the hospital X-ray register for the period 1988-1995, and forearm bone mineral density (BMD) was available in a subsample of 4,690 who had attended three times. Questions about mental distress (depression, insomnia and coping problems) were repeated three times and analyzed as cumulated exposure. Women who reported being depressed at two time points had an adjusted odds ratio (OR) =2.5 (95% confidence interval [CI] 1.3-4.9) for sustaining a non-vertebral fracture and OR=3.1 (95% CI 1.3-7.2) for sustaining an osteoporotic fracture, compared with those without depression on any occasion. The corresponding odds ratios for those with coping problems at two time points were slightly higher, whereas sleeping problems seem only to be weakly associated with non-vertebral fractures. The pattern of associations and the magnitude of OR estimates were mainly the same in women younger than 50 years and those 50 years and older. Women using nerve medicine and reporting depression twice had an odds ratio of 4.4 (95% CI 1.1-17.7) for sustaining a non-vertebral fracture, and those using nerve medicine and reporting coping problems twice had a corresponding OR 4.7 (95% CI 1.2-18.4). Among men no significant associations were found for either fracture type. No association was found between mean BMD and number of times reporting depression, insomnia or coping problems, in women or men. Long-term mental distress is associated with risk of all non-vertebral fractures and osteoporotic fractures in middle-aged women, but not in men. Mental distress itself seems to be more important than the use of nerve medicine.

Adrenal Steroid Hormones and Metaphyseal Bone in Children

BACKGROUND/OBJECTIVES

The responses of metaphyseal bone tissue to physiological variations of endogenous adrenal steroid hormones during childhood are unclear. Therefore, we studied potential hormonal influences in children before the appearance of pubic hair (onset of pubarche).

METHODS

Excretions of major glucocorticoid metabolites (C21), cortisol, sum of adrenarchal dehydroepiandrosterone and its immediate 16-hydroxylated metabolites (DHEA&M), and 5-androstene-3beta,17beta-diol (hermaphrodiol) were analyzed in a cross-sectional study in 24-hour urine samples of 109 healthy boys and girls, aged 6-13 years, using steroid profiling by gas chromatography-mass spectrometry. Total and trabecular volumetric bone mineral densities, bone mineral content (BMC) and bone strength strain index were determined with peripheral quantitative computed tomography at the distal forearm.

RESULTS

In multiple regression analyses significant associations with the metaphyseal radius were seen for grip force, age, or BMI depending on gender and bone variable analyzed. DHEA&M did not contribute to the explanation of the variance of any bone variable. However, hermaphrodiol positively explained a significant part of variation of bone mineral densities, and BMC (p < 0.01) in girls. Significantly negative associations with all bone variables were seen in boys for cortisol.

CONCLUSIONS

The steroid hormones, cortisol and hermaphrodiol, in their physiological ranges, but not the adrenarche marker DHEA&M, appear to associate with metaphyseal bone in a sex-dependent manner during childhood.

Sensitivity of bone to glucocorticoids

Glucocorticoids are used widely in a range of medical specialities, but their main limitation is an adverse impact on bone. Although physicians are increasingly aware of these deleterious effects, the marked variation in susceptibility between individuals makes it difficult to predict who will develop skeletal complications with these drugs. Although the mechanisms underlying the adverse effects on bone remain unclear, the most important effect appears to be a rapid and substantial decrease in bone formation. This review will examine recent studies that quantify the risk of fracture with glucocorticoids, the mechanisms that underlie this increase in risk and the potential basis for differences in individual sensitivity. An important determinant of glucocorticoid sensitivity appears to be the presence of glucocorticoid-metabolizing enzymes within osteoblasts and this may enable improved estimates of risk and generate new approaches to the development of bone-sparing anti-inflammatory drugs.

Intentional and unintentional weight loss increase bone loss and hip fracture risk in older women

OBJECTIVES

To test the hypothesis that unintentional weight loss increases the rate of bone loss and risk of hip fracture more than intentional weight loss.

DESIGN

Prospective cohort study.

SETTING

Four communities within the United States.

PARTICIPANTS

Six thousand seven hundred eighty-five elderly white women with measurement of weight change and assessment of intention to lose weight.

MEASUREMENTS

Weight change between baseline and fourth examinations (average 5.7 years between examinations) and assessment of intention to lose weight. Weight loss was defined as a decrease of 5% or more from baseline weight, stable weight was defined as less than a 5% change from baseline weight, and weight gain was defined as an increase of 5% or more from baseline weight. Rate of change in bone mineral density at the hip between fourth and sixth examinations (average 4.4 years between examinations) was measured using dual-energy x-ray absorptiometry. Incident hip fractures occurring after the fourth examination until June 1, 2001 (average follow-up 6.6 years) was confirmed using radiographic reports.

RESULTS

The adjusted average rate of decline in total hipbone density steadily increased from -0.52% per year in women with weight gain to -0.68% per year in women with stable weight to -0.92% per year in women with weight loss (P-value for trend <.001). Higher rates of hip-bone loss were observed in women with weight loss irrespective of body mass index (BMI) or intention to lose weight. During follow-up of an average 6.6 years after the fourth examination, 400 (6%) of the cohort suffered a first hip fracture. Women with weight loss had 1.8 times the risk (95% confidence interval (CI)=1.43-2.24) of subsequent hip fracture as those with stable or increasing weight. The association between weight loss and increased risk of hip fracture was consistent across categories of BMI and intention to lose weight. Even voluntary weight loss in overweight women with a BMI of 25.9 kg/m2 (median) or greater increased the risk of hip fracture (multivariate hazard ratio=2.48, 95% CI=1.33-4.62).

CONCLUSION

Older women who experience weight loss in later years have increased rates of hip-bone loss and a two-fold greater risk of subsequent hip fracture, irrespective of current weight or intention to lose weight. These findings indicate that even voluntary weight loss in overweight elderly women increases hip fracture risk.

Cognitive dietary restraint is associated with eating behaviors, lifestyle practices, personality characteristics and menstrual irregularity in college women

This study characterized associations of restraint with selected physical, lifestyle, personality and menstrual cycle characteristics in female university students. The survey instrument, distributed to 1350 women, included standardized questionnaires (Three-Factor Eating Questionnaire, Perceived Stress Scale and Rosenberg's Self-esteem Scale), and assessed weight and dieting history, exercise, lifestyle characteristics, menstrual cycle characteristics and whether participants were following vegetarian diets. Among the 596 respondents included in the analysis (44%), women with high (n=145), medium (n=262) or low (n=189) restraint had similar ages, heights and weights. Despite this, compared to women with low scores, those with high scores exercised more (4.6+/-5.3 vs. 3.2+/-3.5 h/wk), were more likely to be vegetarian (14.5 vs. 3.7%), have a history of eating disorders (13.7 vs. 1.2%), be currently trying to lose weight (80.3 vs. 15.3%), report irregular menstrual cycles (34.7 vs. 17.0%), and have scores reflecting lower self-esteem and higher perceived stress. Menstrual irregularity was an independent predictor of restraint score, and restraint score was the only variable to differentiate women with regular and irregular menstrual cycles. We conclude that women with high restraint may use a combination of behavioral strategies for weight control, and differ from women with low restraint scores in personality characteristics and weight history. Some of these behaviors or characteristics may influence menstrual function.

Cortisol, DHEAS and aging: resistance to cortisol suppression in frail institutionalized elderly

Convincing evidences has linked the hypothalamus-pituitary-adrenal (HPA) axis to aging patterns. F excess is implicated in the development of frailty characteristics whereas DHEAS is positively correlated to successful aging. We compared serum F and DHEAS levels of independent community-living (successful group, 19 M and 28 F, 69 to 87 yr) with those of institutionalized elderly (frail group, 20 M and 30 F, 65 to 95 yr). Serum F was determined at 1) baseline (08:00 h, 16:00 h and 23:00 h), 2) after 2 overnight dexamethasone (DEX) suppression tests (DST, using 0.25 and 1.0 mg doses), and 3) 60 min after ACTH stimulation (250 microg i.v. bolus); serum DHEAS was determined at 08:00 h. Basal serum F at 08:00 h, 16:00 h and 23:00 h and serum DHEAS levels were similar in both groups; however F: DHEAS ratio at 08:00 h was higher in the frail, compared to the successful group (mean +/- SD: 0.55 +/- 0.53 and 0.35 +/- 0.41, respectively; p = 0.04). In response to DST, F suppression was less effective in frail elderly after either 0.25 or 1.0 mg doses (9.0 +/- 6.0 and 2.0 +/- 0.9 microg/dl), as compared to the successful group (5.8 +/- 4.4 and 1.5 +/- 0.5 microg/dl) (p = 0.01). In addition, a significant correlation was observed between post-DEX F levels (both doses) and parameters of cognitive and physical frailty. Normal and similar F levels were observed after ACTH stimulation in both groups. Our data suggest a deficient feedback regulation of the HPA axis in frail institutionalized elderly, as demonstrated by a higher set point for F suppression. This augmented HPA tonus enforces the hypothesis that even milder F excess may be related to characteristics of frailty in the elderly.

Urinary free cortisol is similar in older and younger women

The increased cortisol secretion that occurs with aging is associated with characteristics of frailty. In this study we investigated whether healthy elderly women excrete increased amounts of urinary free cortisol (UFC) when compared to younger women. Twenty-four-hour UFC levels were measured in 25 elderly (70 to 87 years of age; median: 74) and 24 younger (19 to 59 years of age; median: 46) community-living women. All subjects were healthy and cognition was unimpaired. No differences in 24-hr UFC were observed between elderly and younger women (54.2 +/- 28.0 and 45.1 +/- 15.6 micrograms/24 hr, respectively) and no correlation was found between 24-hr UFC and age. Also, elderly and younger women had similar 24-hr urinary volumes (1366 +/- 531 and 1514 +/- 412 ml 24 hr, respectively) that did not correlate with UFC. In conclusion, older and younger healthy women have similar 24-hr UFC levels, possibly reflecting a comparable adrenocortical secretion of cortisol.

Rapid resting heart rate: a simple and powerful predictor of osteoporotic fractures and mortality in older women

OBJECTIVES

To determine whether resting heart rate is associated with several types of osteoporotic fractures, mortality, and cause-specific mortality in older women.

DESIGN

A prospective cohort study.

SETTING

Four communities across the United States.

PARTICIPANTS

We prospectively assessed resting pulse rate in 9,702 women aged 65 and older enrolled in the Study of Osteoporotic Fractures.

MEASUREMENTS

Resting pulse was measured in the supine position. Hip, humerus, pelvis, rib, ankle, and wrist fractures were identified by self-report and validated by radiographs. Incident vertebral fractures were assessed by quantitative morphometry. Cause-specific mortality was assessed from death certificates and hospital discharge summaries.

RESULTS

Women with resting heart rates of greater than 80 beats per minute (bpm) (n = 1,140 (12%)) had an adjusted 1.6-fold (95% confidence interval (CI) = 1.2-2.0) increased risk of either a hip, pelvis, or rib fracture and a 1.9-fold (95% CI = 1.4-2.5) increased risk of vertebral fracture. A heart rate of 80 bpm or greater was also associated with 1.4-fold (95% Cl = 1.2-1.5) increased all-cause mortality and 1.5-fold (95% CI = 1.2-2.1) increased coronary heart disease mortality. Investigating resting heart rate as a continuous variable, we detected a general pattern of increasing risks with higher heart rate that could not be explained by age, weight, poor health, physical activity, hyperthyroidism, or smoking.

CONCLUSIONS

Older women with resting heart rates of 80 bpm or more have an increased risk of several osteoporotic fractures and of mortality that is not explained by other risk factors. Heart rate may be a simple tool for assessing risk of fracture and of death from coronary heart disease in older women.

Eating attitudes and habitual calcium intake in peripubertal girls are associated with initial bone mineral content and its change over 2 years

This 2-year prospective study examined associations among bone mineral acquisition and physical, maturational, and lifestyle variables during the pubertal transition in healthy girls. Forty-five girls, initially 10.5+/-0.6 years, participated. Body composition and bone mineral content (BMC) at the spine and total body (TB) were assessed at baseline and annually thereafter using dual-energy X-ray absorptiometry (DXA). Nutrient intakes were assessed using 3-day diet records and a calcium food frequency questionnaire (FFQ), physical activity by questionnaire, sexual maturation using Tanner's stages of breast and pubic hair maturation, growth by height and weight, and eating attitudes using the children's Eating Attitudes Test (Children's EAT). Mean children's EAT subscale scores (dieting, oral control [OC], and bulimia) were stable over time. Median split of OC subscale scores was used to form high and low OC groups. Groups had similar body composition, dietary intake, activity, and Tanner stage at baseline and 2 years. Using height, weight, and Tanner breast stage as covariates, girls with low OC scores had greater TB BMC at baseline (1452+/-221 g vs. 1387+/-197 g; p = 0.030) and 2 years (2003+/-323 g vs. 1909+/-299 g; p = 0.049) and greater lumbar spine (LS) BMC at 2 years (45.2+/-8.8 g vs. 41.2+/-9.6 g; p = 0.042). In multiple regression analysis, OC score predicted baseline, 2 years, and 2-year change in TB and spinal BMC, contributing 0.9-7.6% to explained variance. Calcium intake predicted baseline, 2 years, and 2-year change in TB BMC, explaining 1.6-5.3% of variance. We conclude that both OC and habitual calcium intake may influence bone mineral acquisition.

Cortisol and GH secretory dynamics, and their interrelationships, in healthy aged women and men

We studied 130 healthy aged women (n = 57) and men (n = 73), age 65-88 yr, with age-related reductions in insulin-like growth factor I and gonadal steroid levels to assess the interrelationships between cortisol and growth hormone (GH) secretion and whether these relationships differ by sex. Blood was sampled every 20 min from 8:00 PM to 8:00 AM; cortisol was measured by RIA and GH by immunoradiometric assay, followed by deconvolution analyses of hormone secretory parameters and assessment of approximate entropy (ApEn) and cross-ApEn. Cortisol mass/burst, cortisol production rate, and mean and integrated serum cortisol concentrations (P < 0.0005), and overnight basal GH secretion (P < 0.05), were elevated in women vs. men. Integrated cortisol concentrations were directly related to most measures of GH secretion in women (P < 0.01) and with mean and integrated GH concentrations in men (P < 0.05). Integrated GH concentrations were directly related to mean and integrated cortisol levels in women (P < 0.005) and men (P < 0.05), with no sex differences. There were no sex differences in cortisol or GH ApEn values; however, the cross-ApEn score was greater in women (P < 0.05), indicating reduced GH-cortisol pattern synchrony in aged women vs. men. There were no significant relationships of integrated cortisol secretion with GH ApEn, or vice versa, in either sex. Thus postmenopausal women appear to maintain elevated cortisol production in patterns that are relatively uncoupled from those of GH, whereas mean hormone outputs remain correlated.

Cognitive dietary restraint is associated with higher urinary cortisol excretion in healthy premenopausal women

BACKGROUND

Cognitive dietary restraint, assessed by the Three-Factor Eating Questionnaire restraint subscale, is associated with subclinical menstrual cycle disturbances. This association may be mediated by stress-activated cortisol release.

OBJECTIVE

We assessed whether 24-h urinary cortisol excretion differs between women with high and low restraint scores.

DESIGN

Participants (aged 21.6+/-2.5 y; n = 62) with normal-length menstrual cycles and high (n = 33) or low (n = 29) restraint scores completed a questionnaire describing weight history, dietary practices, and exercise. Cortisol, calcium, and creatinine were measured in urine collected over 24 h on a day when all food and beverages were provided and measured. Previously, 3-d food records and anthropometric measurements were obtained.

RESULTS

Age, height, weight, body mass index, and length of menstrual cycle were similar between groups. The reported amount of exercise was higher (3.4+/-1.7 compared with 2.2+/-1.8 h/wk; P<0.05) and energy intakes (assessed from 3-d and 24-h food records) were lower in the high- than in the low-restraint group. Ratios of urinary cortisol (nmol) to creatinine (mmol) were higher in the high-restraint than in the low-restraint group (42.9+/-12.9 compared with 36.3+/-8.9; P<0.05), whereas ratios of urinary calcium (mmol) to creatinine were lower (0.3+/-0.1 compared with 0.4+/-0.2; P<0.05) in the high-restraint group. Urinary cortisol was not associated with exercise, nutrient intakes, or anthropometric measurements.

CONCLUSIONS

High dietary restraint scores are associated with urinary cortisol, a biological marker of stress, and high cortisol excretion may affect bone health. Our results suggest that further research is warranted to clarify these associations and to determine whether they persist over time.

The role of bone turnover markers and risk factors in the assessment of osteoporosis and fracture risk

The clinical evaluation of osteoporosis in individual patients involves confirmation of the diagnosis, the investigation of secondary causes of osteoporosis and the evaluation of subsequent fracture risk. Optimum clinical assessment involves bone mineral densitometry with the treatment thresholds modified by clinical risk factors for individual patients. Bone turnover markers and clinical risk factors can be used to identify patients at risk of osteoporotic fracture and those who have secondary osteoporosis. Risk assessment should involve the evaluation of absolute rather than relative risk. Further work is required to improve the integration of clinical risk factors, bone turnover markers and bone densitometry into appropriate models to enable the assessment of the absolute risk of fracture for individual patients.