Polycystic ovary syndrome: associations with cardiovascular disease

Polycystic ovary syndrome (PCOS), characterized by abnormal menstrual periods, elevated androgen levels and polycystic ovary morphology on ultrasound, is the most common endocrine disorder among females. PCOS is associated with cardiovascular disease (CVD) risk factors including diabetes, obesity, metabolic syndrome, adverse pregnancy outcomes such as pre-eclampsia and psychosocial distress including depression. Previous evidence on the association between PCOS and CVD is inconclusive but the latest 2023 International Evidence-Based PCOS Guideline identifies PCOS as a risk factor for CVD. This review will discuss the relationship between PCOS and CVD along with current direction for CVD screening and prevention among individuals with PCOS.

Learning health systems and evidence ecosystems: a perspective on the future of evidence-based medicine and evidence-based guideline development

Despite forming the cornerstone of modern clinical practice for decades, implementation of evidence-based medicine at scale remains a crucial challenge for health systems. As a result, there has been a growing need for conceptual models to better contextualise and pragmatize the use of evidence-based medicine, particularly in tandem with patient-centred care. In this commentary, we highlight the emergence of the learning health system as one such model and analyse its potential role in pragmatizing both evidence-based medicine and patient-centred care. We apply the learning health system lens to contextualise the key activity of evidence-based guideline development and implementation, and highlight how current inefficiencies and bottlenecks in the evidence synthesis phase of evidence-based guideline development threaten downstream adherence. Lastly, we introduce the evidence ecosystem as a complementary model to learning health systems, and propose how innovative developments from the evidence ecosystem may be integrated with learning health systems to better enable health impact at speed and scale.

Development, women-centricity and psychometric properties of maternity patient-reported outcome measures (PROMs): A systematic review

BACKGROUND

Measuring maternity care outcomes based on what women value is critical to promoting woman-centred maternity care. Patient-reported outcome measures (PROMs) are instruments that enable service users to assess healthcare service and system performance.

AIM

To identify and critically appraise the risk of bias, woman-centricity (content validity) and psychometric properties of maternity PROMs published in the scientific literature.

METHODS

MEDLINE, CINAHL Plus, PsycINFO and Embase were systematically searched for relevant records between 01/01/2010 and 07/10/2021. Included articles underwent risk of bias, content validity and psychometric properties assessments in line with COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidance. PROM results were summarised according to language subgroups and an overall recommendation for use was determined.

FINDINGS

Forty-four studies reported on the development and psychometric evaluation of 9 maternity PROMs, grouped into 32 language subgroups. Risk of bias assessments for the PROM development and content validity showed inadequate or doubtful methodological quality. Internal consistency reliability, hypothesis testing (for construct validity), structural validity and test-retest reliability varied markedly in sufficiency and evidence quality. No PROMs received a level 'A' recommendation, required for real-world use.

CONCLUSION

Maternity PROMs identified in this systematic review had poor quality evidence for their measurement properties and lacked sufficient content validity, indicating a lack of woman-centricity in instrument development. Future research should prioritise women's voices in deciding what is relevant, comprehensive and comprehensible to measure, as this will impact overall validity and reliability and facilitate real-world use.

Levels of physical activity and sitting time in women with infants, toddlers and preschoolers: a population-based cross-sectional study

OBJECTIVES

Insufficient physical activity (PA) and prolonged sitting time (ST) increase the risk of chronic disease and mortality. Caring for young children can potentially impact maternal PA and sedentary behaviours. The aims of this study were to explore the levels of PA and ST in women with young children (infants, toddlers and preschoolers) and sociodemographic and behavioural factors associated with these.

STUDY DESIGN

This was a population-based cross-sectional study.

METHODS

Survey 5 data collected in 2009 (n = 4290) of the 1973-1978 birth cohort of the Australian Longitudinal Study on Women's Health were used. Multiple linear and logistic regression models were used to examine associations.

RESULTS

In adjusted models, compared with women with preschoolers, women whose youngest child was an infant aged 0-6 months, aged >6-12 months or toddler had lower PA (-321.3 MET.min/week [95% confidence interval (CI) -416.2, -226.4], -147.9 MET.min/week [95% CI -237.6, -58.1] and -106.4 MET.min/week [95% CI -172.3, -40.5]). ST was higher in women whose youngest child was an infant aged 0-6 months (0.48 h/day; 95% CI 0.19, 0.77) but lower with infants aged >6-12 months (-0.33 h/day; 95% CI -0.60, -0.05) and toddlers (-0.40 h/day; 95% CI -0.60, -0.20) than in those with preschoolers. The findings were similar in the logistic model. Sociodemographic and behavioural factors such as occupation and marital status also influenced PA and ST.

CONCLUSIONS

Women with infants and toddlers have lower PA than women with preschoolers. Women are more likely to sit more in the first 6 months after childbirth. These findings can inform resources and intervention development to improve activity levels in women with young children through consideration of the age of the youngest child, sociodemographic and behavioural factors.

Is parity a risk factor for excessive weight gain during pregnancy and postpartum weight retention? A systematic review and meta-analysis

The aim of this study was to systematically review and meta-analyse the associations between parity, pre-pregnancy body mass index (BMI), gestational weight gain (GWG) and, when included, postpartum weight retention (PPWR). Papers reporting associations between parity and BMI and/or GWG in adult women were eligible: 2,195 papers were identified, and 41 longitudinal studies were included in the narrative synthesis; 17 studies were included in a meta-analysis. Findings indicated that parity was associated positively with pre-pregnancy BMI. In contrast, the role of parity in GWG was less clear; both positive and negative relationships were reported across studies. Parity was not associated directly with PPWR. This pattern of results was supported by our meta-analysis with the only significant association between parity and pre-pregnancy BMI. Overall, parity was associated with higher pre-pregnancy BMI; however, the role of parity in GWG and PPWR remains unclear, and it is likely that its influence is indirect and complex. Further research to better understand the contribution of parity to maternal obesity is warranted.

Gaps and barriers in health-care provision for co-morbid diabetes and chronic kidney disease: a cross-sectional study

BACKGROUND

Patients with diabetes and chronic kidney disease (CKD) are a complex subset of the growing number of patients with diabetes, due to multi-morbidity. Gaps between recommended and received care for diabetes and chronic kidney disease (CKD) are evident despite promulgation of guidelines. Here, we document gaps in tertiary health-care, and the commonest patient-reported barriers to health-care, before exploring the association between these gaps and barriers.

METHODS

This cross-sectional study recruited patients with diabetes and CKD (eGFR < 60 mL/min/1.73 m2) across 4 large hospitals. For each patient, questionnaires were completed examining clinical data, recommended care, and patient-reported barriers limiting health-care. Descriptive statistics, subgroup analyses by CKD stage and hospital, and analyses examining the relationship between health-care gaps and barriers were performed.

RESULTS

308 patients, of mean age 66.9 (SD 11.0) years, and mostly male (69.5%) and having type 2 diabetes (88.0%), participated. 49.1% had stage 3, 24.7% stage 4 and 26.3% stage 5 CKD. Gaps between recommended versus received care were evident: 31.9% of patients had an HbA1c ≥ 8%, and 39.3% had a measured blood pressure ≥ 140/90 mmHg. The commonest barriers were poor continuity of care (49.3%), inadequate understanding/education about CKD (43.5%), and feeling unwell (42.6%). However, barriers associated with a failure to receive items of recommended care were inadequate support from family and friends, conflicting advice from and poor communication amongst specialists, the effect of co-morbidities on self-management and feeling unmotivated (all p < 0.05).

CONCLUSIONS

Barriers to health-care varied across CKD stages and hospitals. Barriers associated with a deviation from recommended care were different for different items of care, suggesting that specific interventions targeting each item of care are required.

Young women's psychological distress after a diagnosis of polycystic ovary syndrome or endometriosis

STUDY QUESTION

Do young women with polycystic ovary syndrome (PCOS) or endometriosis report more psychological distress than their peers without a history of these conditions?

SUMMARY ANSWER

Young women (aged 18-23 years) with PCOS or endometriosis had a greater risk of moderate to severe psychological distress than women without a history of these conditions.

WHAT IS KNOWN ALREADY

Psychological distress appears common among women with PCOS and endometriosis. However, population-based studies that examine the psychological outcomes for adolescents and young women are generally absent from the literature.

STUDY DESIGN, SIZE, DURATION

This is a secondary analysis of data collected from 17 015 young, Australian women participating in a national, longitudinal cohort study. Women were first surveyed in 2012-2013 when they were aged 18-23 years. In 2014, women completed the second survey when they were aged 19-24 years and 11324 (67%) women responded.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We analysed data from 11 238 women who participated in both Surveys 1 and 2 and who responded to questions about PCOS and endometriosis. Using logistic regression, we compared the odds of moderate to severe psychological distress at Surveys 1 and 2 for women reporting a recent diagnosis (within the last 12 months) of PCOS or endometriosis and women with a pre-existing diagnosis, with that for women without a history of these conditions.

MAIN RESULTS AND THE ROLE OF CHANCE

At Survey 2, around 60% of women reporting a diagnosis of PCOS or endometriosis had moderate to severe levels of psychological distress. Compared to women without a history of these conditions, the odds of moderate to severe psychological distress at Survey 2 were significantly higher for women recently diagnosed with PCOS [Adjusted Odds Ratio (AOR) = 1.62, 95% CI = 1.21-2.18] or endometriosis (AOR= 1.77; 95% CI = 1.20-2.63) and for women with a pre-existing diagnosis of PCOS (AOR = 1.57, 95% CI = 1.30-1.89) or endometriosis (AOR = 1.61; 95% CI = 1.26-2.06). Women recently diagnosed with PCOS or endometriosis also had a greater likelihood of moderate to severe distress in the year prior to their diagnosis. The association between PCOS and psychological distress was attenuated when adjusting for BMI, but hormonal contraceptive use did not attenuate the risk of distress among the women with PCOS or endometriosis.

LIMITATIONS, REASONS FOR CAUTION

All data were self-reported and, therefore, the diagnoses of PCOS or endometriosis were not confirmed by a medical practitioner.

WIDER IMPLICATIONS OF THE FINDINGS

Health professionals should be aware of the potential psychosocial and healthcare needs among young women with these conditions, particularly women with PCOS who are obese. While hormonal contraceptives may help to regulate the hormonal aspects of these conditions, they do not appear to reduce women's psychological distress. Because psychological distress among the young women in this study remained elevated even after diagnosis, this supports the need for multidisciplinary health care to help women adjust to their diagnosis and treatment regimens and facilitate positive, long-term mental health outcomes. Future research that examines medical and psychosocial sources of distress for young women with PCOS and endometriosis is needed.

STUDY FUNDING/COMPETING INTERESTS

I.J.R. was supported by an Australian National Health and Medical Research Council Centre for Research Excellence (grant number: APP1000986). G.D.M. is funded by the Australian Research Council Future Fellowship (FT120100812). The Australian Longitudinal Study on Women's Health is funded by the Australian Government Department of Health. H.T. is supported by an Australian National Health and Medical Research Council Practitioner Fellowship. The authors declare that no competing interests exist.

TRIAL REGISTRATION NUMBER

N/A.

Symptoms, health behavior and understanding of menopause therapy in women with premature menopause

OBJECTIVE

To explore symptoms, understanding of menopausal therapies, medication use and health-related behavior in women with and without premature menopause.

METHODS

Cross-sectional, questionnaire-based study involving a community-based sample of 77 women in Australia: 23 premenopausal, 25 with premature ovarian failure (POF) and 29 with medically induced premature menopause (MIPM).

RESULTS

The median (interquartile range) age of each group was: premenopausal = 29 (13) years, POF = 36 (8.0) years and MIPM = 38 (4.0) years (p < 0.001). The reported frequency of menopausal symptoms differed across the groups for difficulty sleeping (premenopausal = 26%, POF = 44%, MIPM = 69%, p = 0.01), some depression symptoms (premenopausal = 4.4-22%, POF = 20-25%, MIPM = 38-59%, p < 0.05), hot flushes (premenopausal = 4.4%, POF = 28%, MIPM = 59%, p < 0.001), sweating at night (premenopausal = 4.4%, POF = 20%, MIPM = 52%, p < 0.001) and loss of interest in sex (premenopausal = 17%, POF = 52%, MIPM = 54%, p = 0.02). More women with premature menopause than premenopausal women reported taking prescription medication (premenopausal = 52%, POF = 92%, MIPM = 86%, p = 0.002), perceived that hormone therapy (HT) was associated with increased breast cancer risk (premenopausal = 43%, POF = 56%, MIPM = 79%, p = 0.03) and that HT prevented fractures (premenopausal = 13%, POF = 56%, MIPM = 39%, p = 0.01). Most women reported not knowing risks/benefits of bioidentical hormone therapy (premenopausal = 86%, POF = 56%, MIPM = 75%, p = 0.06). Regarding health-related behavior around prevention and screening, varying rates of bone densitometry (premenopausal = 4.4%, POF = 64%, MIPM = 59%, p < 0.001), blood glucose testing (premenopausal = 39%, POF = 67%, MIPM = 57%, p = 0.16) and cholesterol testing (premenopausal = 22%, POF = 71%, MIPM = 54%, p = 0.003) were reported.

CONCLUSIONS

Differences in understanding of menopausal therapies and health-related behavior exist among women with premature menopause of differing etiology and premenopausal women. While perceived understanding of HT was greater than other therapies, targeted education is needed regarding specific risks/benefits of menopausal therapies and regarding preventive health screening after premature menopause.

Breast cancer and menopause: perceptions of diagnosis, menopausal therapies and health behaviors

OBJECTIVES

The aim of this study was to investigate the perception and experience of menopause diagnosis and therapies, the information provided and health behaviors in younger women with breast cancer.

METHODS

The questionnaire study was completed by 114 women, aged 40-51 years, with non-metastatic breast cancer. Women were recruited from outpatient clinics and the community. Descriptive statistics were completed.

RESULTS

Most women were satisfied with the manner in which they were informed of the breast cancer (69%) and the menopause (59%) diagnoses. Although 80% of women were given breast cancer information, only 54% were given menopause information at diagnosis. Women were least satisfied (26%) with information regarding the long-term complications of menopause. Women perceived exercise (68%) and improving lifestyle (61%) as most effective in alleviating symptoms of menopause. The majority of women reported that they did not understand the risks/benefits of 'bioidentical' hormones (79%) and herbal therapies (78%), while 58% perceived hormone replacement therapies as associated with an increased risk of breast cancer. Most women reported weight gain (68%) and osteoporosis (67%) as the most common problems/fears regarding menopause. However, regarding health behaviors, only 56% reported having relevant tests including a blood sugar test or a bone density test.

CONCLUSION

While information needs regarding breast cancer appear well met in younger women, unmet information needs regarding menopause after breast cancer persist. Further education and support are required for these women to optimize health screening and prevention behaviors and to ensure informed decision-making regarding menopause treatment options.

Polycystic ovary syndrome: a complex condition with psychological, reproductive and metabolic manifestations that impacts on health across the lifespan

Polycystic ovary syndrome (PCOS) is of clinical and public health importance as it is very common, affecting up to one in five women of reproductive age. It has significant and diverse clinical implications including reproductive (infertility, hyperandrogenism, hirsutism), metabolic (insulin resistance, impaired glucose tolerance, type 2 diabetes mellitus, adverse cardiovascular risk profiles) and psychological features (increased anxiety, depression and worsened quality of life). Polycystic ovary syndrome is a heterogeneous condition and, as such, clinical and research agendas are broad and involve many disciplines. The phenotype varies widely depending on life stage, genotype, ethnicity and environmental factors including lifestyle and bodyweight. Importantly, PCOS has unique interactions with the ever increasing obesity prevalence worldwide as obesity-induced insulin resistance significantly exacerbates all the features of PCOS. Furthermore, it has clinical implications across the lifespan and is relevant to related family members with an increased risk for metabolic conditions reported in first-degree relatives. Therapy should focus on both the short and long-term reproductive, metabolic and psychological features. Given the aetiological role of insulin resistance and the impact of obesity on both hyperinsulinaemia and hyperandrogenism, multidisciplinary lifestyle improvement aimed at normalising insulin resistance, improving androgen status and aiding weight management is recognised as a crucial initial treatment strategy. Modest weight loss of 5% to 10% of initial body weight has been demonstrated to improve many of the features of PCOS. Management should focus on support, education, addressing psychological factors and strongly emphasising healthy lifestyle with targeted medical therapy as required. Monitoring and management of long-term metabolic complications is also an important part of routine clinical care. Comprehensive evidence-based guidelines are needed to aid early diagnosis, appropriate investigation, regular screening and treatment of this common condition. Whilst reproductive features of PCOS are well recognised and are covered here, this review focuses primarily on the less appreciated cardiometabolic and psychological features of PCOS.

A biochanin-enriched isoflavone from red clover lowers LDL cholesterol in men

OBJECTIVE

To determine whether the two major isoflavones in red clover differ in their effect on low-density lipoprotein cholesterol (LDL-C).

DESIGN

A randomised, placebo-controlled, double-blind trial; two parallel groups taking one of the two isoflavones within which treatment and placebo were administered in a crossover design.

SETTING

Free-living volunteers.

SUBJECTS

A total of 46 middle-aged men and 34 postmenopausal women.

INTERVENTION

Two mixtures of red clover isoflavones enriched in either biochanin (n=40) or formononetin (n=40) were compared. Placebo and active treatment (40 mg/day) were administered for 6 weeks each in a crossover design within the two parallel groups.

MAIN OUTCOME MEASURES

Plasma lipids were measured twice at the end of each period.

RESULTS

Baseline LDL-C concentrations did not differ significantly between men (n=46) and women (n=34), nor between those randomised to biochanin or formononetin. Interaction between time and treatments, biochanin, formononetin and corresponding placebos (two-way ANOVA) on LDL-C showed a significant effect of biochanin treatment alone. The biochanin effect was confined to men; median LDL-C was 3.61 (3.05-4.14) mmol/l with biochanin and 3.99 (3.16-4.29) mmol/l with the corresponding placebo (RM ANOVA with Dunnett's adjustment P<0.05). The difference between placebo and biochanin effects on LDL-C was 9.5%. No other lipid was affected and women failed to respond significantly to treatment.

CONCLUSION

Isolated isoflavones from red clover enriched in biochanin (genistein precursor) but not in formononetin (daidzein precursor), lowered LDL-C in men. This may partly explain the previous failure to demonstrate cholesterol-lowering effects with mixed isoflavones studied predominantly in women.

SPONSORSHIP

Novogen Ltd, North Ryde NSW, Australia, provided partial support including provision of tablets and outside monitoring.

Gender differences in protein kinase G-mediated vasorelaxation of rat aorta

Although gender and oestrogen treatment influence production of the vasorelaxant, NO, their influence on factors downstream in the NO signal-transduction pathway, specifically protein kinase G (PKG), remains unknown. We aimed to study the influence of sex hormones on PKG, along with the endothelial modulation of these effects, in rat thoracic aortic rings in two separate groups, control male and female rats and ovariectomized female rats after treatment with oestrogen or vehicle. Vessel preparations were preconstricted with phenylephrine (0.1 microM). Constrictions were greater in male than female aortas. This differential effect was attenuated by endothelium removal, addition of the guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, 1 microM) and the nitric oxide synthase (NOS) inhibitor N(G)-monomethyl-L-arginine (L-NMMA, 100 microM), supporting the role of NO in maintenance of basal relaxation and vascular tone in females. We have examined the relative activity of the specific PKG subtypes 1 alpha and 1 beta in vascular smooth muscle, based on relaxation of rat aortas by two cGMP analogues with different selectivity, beta-phenyl-l-N(2)-ethano-8-bromo-cGMP (8-Br-PET-cGMP) and 8-(2-aminophenylthio)cGMP (8-APT-cGMP). 8-Br-PET-cGMP was more potent than 8-APT-cGMP in both sexes, suggesting that PKG 1 alpha is the primary subtype involved in vasorelaxation. The gender differences in PKG activity were examined based on relaxation responses in male and female rat aortas. Both 8-Br-PET-cGMP and 8-APT-cGMP were more potent in aortas from male than female rats. In further studies on the endothelial modulation of relaxation with 8-APT-cGMP, the differential gender-vasorelaxation response was negated by endothelium removal and addition of the guanylate cyclase inhibitor ODQ (1 microM), but not by the NOS inhibitor L-NMMA (100 microM), suggesting that an endothelial-dependent factor other than NO may be responsible for the observed differential PKG-mediated vasorelaxation between the sexes. To further investigate oestrogen influence on PKG, treated female rats were studied. Contrary to our hypothesis, in the presence of 1 microM ODQ, there were no differences in either the phenylephrine constriction, or the relaxation with 8-APT-cGMP from either sham-operated, vehicle-treated or oestrogen-treated ovariectomized rats. In conclusion, female rat aortas have greater basal NO production compared with males. Relaxant responses to PKG activation are greater in aortas from male compared with female rats. These findings suggest hormonal regulation of PKG; however, oestrogen treatment of ovariectomized rats did not affect PKG activity, suggesting factors other than oestrogen may be responsible for the gender differences noted in this study.

Evidence that parenteral testosterone therapy may improve endothelium-dependent and -independent vasodilation in postmenopausal women already receiving estrogen

The gender difference in cardiovascular disease has been partly attributed to higher androgenic hormone levels. Although testosterone in women may not affect lipids, it remains unknown whether it negates favorable estrogenic effects on endothelial function. We have investigated the effects of testosterone implant therapy on arterial reactivity encompassing endothelial-dependent and -independent vasodilation in women using hormone replacement therapy (HRT). B-mode ultrasound measurements of resting brachial artery diameter, following reactive hyperemia [endothelium-dependent flow- mediated dilation (FMD)] and following glyceryl trinitrate (GTN) (endothelium-independent dilation), were recorded in 33 postmenopausal women stabilized on HRT (>6 months), at baseline, and 6 weeks after a testosterone implant (50 mg), with 15 postmenopausal nonusers of HRT serving as controls. In the brachial artery, baseline resting diameter was similar (0.40 +/- 0.01 vs. 0.41 +/- 0.01 cm, P = 0.5). In the treated group, testosterone levels increased (0.99 +/- 0.08 to 4.99 +/- 0.3 nmol/L, P < 0.001), associated with a mean 42% increase in FMD (6.4% +/- 0.7 to 9.1% +/- 1.1, P = 0.03). The control group did not change (8.1% +/- 1.4 to 5.6% +/- 1.0, P = 0.4). ANOVA of repeated measures (P = 0.04) and mean change (P = 0.02) in FMD both demonstrated significantly greater improvement with testosterone compared with controls. GTN induced vasodilation increased with testosterone treatment (14.9% +/- 0.9 to 17.8% +/- 1.2, P = 0.03). Our preliminary data indicate that parenteral testosterone therapy improves both endothelial-dependent (flow-mediated) and endothelium-independent (GTN-mediated) brachial artery vasodilation in postmenopausal women using long-term estrogen therapy. The mechanisms underlying these potentially beneficial cardiovascular effects require further investigation.

Non-invasive measurements of arterial structure and function: repeatability, interrelationships and trial sample size

1. Repeatability of measurements of arterial compliance and flow-mediated dilation of the brachial artery has been infrequently reported, despite increasing use in interventional and risk-factor modification studies. Furthermore, little is known about the interrelationships of the various indices. The purposes of this study were to determine the repeatability and interrelationships of a range of arterial indices.2. Fifty healthy volunteers, 20 men and 30 women, aged 20-70 (mean 46.5) years, were studied on two occasions, using an identical protocol, at a mean interval of 2.5 weeks. Tonometry, ultrasound and Doppler technique were used to measure the following: carotid wall intima-media thickness (IMT), total systemic artery compliance (SAC), arterial pulse wave velocity [PWV aorto-femoral (A-F), and femoral-dorsalis pedis (F-D)], carotid distensibility coefficient (DC) and carotid augmentation index (AI). Brachial flow-mediated dilation was measured in 30 subjects with analysis of diameter change for 4 min post ischaemia.3. There were no systematic differences over the observed range of measurements for any of the reported parameters. Coefficients of variation were as follows: IMT 2.8%, SAC 9.2%, PWV(A-F) 3.2%, PWV(F-D) 5.0%, DC 10.0%, AI 1.3%. Brachial flow-mediated dilation curves were not different between visits; changes were maximum 60-s post ischaemia. All indices of arterial compliance were significantly correlated with age. The three different indices of central arterial compliance [SAC, PWV(A-F) and AI] were significantly correlated with carotid intima-media thickness.4. Under controlled experimental conditions there was good repeatability of measurements of indices between sessions of both intrinsic and functional arterial mechanical properties (central and carotid arterial compliance, intima-media thickness and brachial flow-mediated dilation). Sample size tables for clinical trials using these indices are presented.

Reproducibility of arterial compliance and carotid wall thickness measurements in normal subjects

1. Non-invasive techniques to measure indices of arterial function and wall thickness are frequently used as surrogate markers of cardiovascular disease. Reproducibility of measurements of arterial compliance has been infrequently reported and little is known about the interrelationships of the various indices in vivo. 2. The present study was designed to assess reproducibility and interrelationships of indices of systemic arterial compliance, pulse wave velocity, carotid compliance and intima-media thickness (IMT). 3. Fifty healthy volunteers (20 male and 30 female: aged 20-70 years, mean 46.5 years), participated in the present study. Each subject was studied on two occasions by the same investigators, using an identical protocol at an interval of 1-5 weeks (mean 2.5 weeks) without lifestyle change. 4. There were no significant differences between visits for any recorded general data, except resting blood pressure, which was lower on the second occasion. There were no systematic differences within each pair over the range of measurements for any of the variables. Bland-Altman plots of repeatability of changes in indices showed that the mean values between visits were not significantly different. All indices of central arterial compliance were significantly related to age and IMT. 5. Thus, under controlled experimental conditions, there was satisfactory repeatability of measurements of indices of both intrinsic and functional arterial mechanical properties (central and carotid arterial compliance and IMT). This type of information will permit the construction of sample size tables for clinical trials using these indices. 6. Central arterial compliance may be an important determinant of IMT.

Age-related deterioration in arterial structure and function in postmenopausal women: impact of hormone replacement therapy

Epidemiological evidence suggests that hormone replacement therapy (HRT) reduces morbidity and mortality from cardiovascular diseases in postmenopausal women. In this study, indices of arterial function [total systemic arterial compliance (SAC) and carotid arterial distensibility coefficient (DC)], structure [carotid intima-media thickness (IMT)], and lipid profiles were compared in postmenopausal women on long-term HRT and aged-matched controls. One hundred nine women aged 44 to 77 years taking HRT and an age-matched group of 108 female controls were entered into the study. The two groups were similar for body mass index, smoking status, exercise level, alcohol intake, and blood pressure. Fasting cholesterol, low density lipoprotein, and lipoprotein(a) were reduced and high density lipoprotein increased in the HRT group. IMT increased with age; SAC and DC were reduced with age in both groups. The HRT group had a higher mean SAC (0.42+/-0.02 versus 0.34+/-0.02 U/mm Hg, P=0.0001) and a lower mean IMT (0.67+/-0.01 versus 0.74+/-0.02 mm, P=0.006) than did controls. Subgroup analysis for estrogen versus estrogen plus progestin revealed no differences for SAC and IMT; DC, however, was greater in estrogen-only users. Smokers on HRT had a higher mean SAC (0.41+/-0.02 versus 0.31+/-0.01 U/mm Hg, P=0.008) and a lower IMT (0.65+/-0.02 versus 0.75+/-0.03 mm, P=0.002) than did smokers not taking such therapy. A protective effect of long-term estrogen therapy on age-related changes in arterial structure and function in postmenopausal women was evident in smokers and nonsmokers alike. Progestin appeared to counteract the effects of estrogen on carotid compliance only. Long-term controlled trials are needed to determine the significance of these findings.

Effects of oestrogen and progesterone on age-related changes in arteries of postmenopausal women

1. Hormone replacement therapy (HRT) with oestrogen or oestrogen plus progestin may have different effects on arterial structure and function. To examine this question, carotid artery intima-medial thickness (IMT) and indices of systemic and carotid arterial compliance were measured in groups of older men, postmenopausal women not on HRT (non-HRT) and those women on long-term HRT with oestrogen alone (HRT-E) or oestrogen plus progestin (HRT-EP). 2. Sixty men, 90 postmenopausal women taking HRT and 91 not taking HRT participated in the study. The groups were similar for age, body mass index, numbers of smokers, physical activity, alcohol intake and blood pressure. 3. Plasma total cholesterol was reduced and high-density lipoprotein-cholesterol was increased in the HRT group compared with the non-HRT group; low-density lipoprotein-cholesterol, triglyceride and lipoprotein (a) values were similar in these two groups. Results for HRT-E and HRT-EP subgroups were similar. 4. Carotid IMT was significantly reduced in the HRT group compared with men and non-HRT groups. Results for HRT-E and HRT-EP subgroups were similar. 5. Mean systemic arterial compliance (SAC) was significantly greater in men than in women and was related to age; SAC was higher in both HRT-E and HRT-EP groups compared with the non-HRT group. Indices of carotid stiffness were similar in men and in non-HRT groups. The HRT-EP group showed increased carotid stiffness compared with the HRT-E group. 6. There is an apparent protective effect of long-term oestrogen therapy on carotid IMT and age-related changes in arterial stiffness. Progestin does not alter the IMT effects but may adversely influence arterial stiffness.

Anticoagulant regimens in acute continuous hemodiafiltration: a comparative study

OBJECTIVE

To compare and contrast different heparin regimens for extracorporeal circuit anticoagulation in patients receiving acute continuous hemodiafiltration (ACHD).

DESIGN

Prospective controlled randomized comparisons of the following regimens: 1) Low dose (500 IU/h) pre-filter heparin versus regional anticoagulation in patients on continuous arteriovenous hemodiafiltration (CAVHD) via A-V shunt. 2) Low dose pre-filter heparin versus no anticoagulation in patients receiving CAVHD via femoral cannulae. 3) Low dose pre-filter heparin versus regional anticoagulation in patients on continuous veno-venous hemodiafiltration (CVVHD). 4) An assessment of the consequences of the use of no anticoagulant in patients predicted to be at high risk of hemorrhagic complications on treatment with CVVHD.

SETTING

University Teaching Hospital ICU.

PATIENTS

64 ICU patients with acute renal failure.

MEASUREMENTS AND MAIN RESULTS

Haemofilter survival during shunt CAVHD was significantly prolonged by the use of regional anticoagulation compared to the use of low dose heparin (mean filter survival: 57.1 h versus 42.9 h; p < 0.05). In CAVHD using femoral cannulae, no significant differences in haemofilter survival were found between anticoagulation with low dose heparin and the use of no anticoagulant (mean filter survival: 55 h versus 52.5 h; NS). During CVVHD, regional anticoagulation compared to low dose heparin produced a trend towards prolonged filter life which was, however, not statistically significant (mean filter survival: 40.5 h versus 31.4 h; NS). In patients assessed to be at high risk of bleeding, CVVHD without anticoagulation provided a mean filter survival of 40.9 h (95% CI 27-54.8 h).

CONCLUSIONS

Regional anticoagulation leads to longer filter survival than low dose heparin in shunt CAVHD. A regimen of no anticoagulation during femoral CAVHD leads to a filter life similar to that of low dose heparinization. During CVVHD, regional anticoagulation and low dose heparin are associated with similar filter survival times. In patients assessed to be at high risk of bleeding, treatment with CVVHD without anticoagulation results in adequate filter survival.