An assessment of the elastic properties of the aorta in nonobese women with polycystic ovary syndrome

Metformin effect on internal carotid artery blood flow assessed by area under the curve of carotid artery Doppler in women with polycystic ovarian syndrome

BACKGROUND

Insulin resistance (IR) was reported in most polycystic ovarian syndrome (PCOS) cases. Metformin, a biguanide drug, successfully reduced IR. Homeostatic Model Assessment for IR (HOMA-IR) and Doppler parameters assessed metformin's effectiveness.

AIM

To verify whether the area under the curve of the internal carotid artery (AUC-ICA) Doppler wave can be a useful marker for assessing IR among PCOS cases who presented with menstrual irregularity and were treated with metformin over 6 mo.

METHODS

An observational, cross-sectional study recruited 54 eligible PCOS women; the anthropometrics were as follows: age, body mass index (BMI), menstrual cycle days, biochemical serum cholesterol, low and high-density lipoprotein, sex hormone-binding globulin, fasting blood glucose, and HOMA-IR, hormonal testosterone, luteinizing hormone over follicle-stimulating hormone ratio, and ultrasonic pulsatility index (PI) and resistance index (RI), carotid artery intima-media thickness (CIMT) and (AUC-ICA) parameters were initially recorded and repeated 3 mo and 6 mo later with metformin tab 500 mg; three times/day for 6 mo. In addition, AUC-ICA was assessed by taking repeated systolic and diastolic wave height measurements.

RESULTS

Metformin caused a progressive reduction in BMI, menstrual cycle days, biochemical hormonal, and Doppler parameters (CIMT, PI, RI, and AUC-ICA). AUC-ICA correlated strongly to all PCOS parameters. AUC-ICA correlated inversely with treatment time (r = -0.98, P < 0.001) and positively with HOMA-IR (r = 0.98, P < 0.0001). Via the best subset regression model, the AUC-ICA had the highest predictive value for HOMA-IR.

CONCLUSION

AUC-ICA preceded PI, RI, and CIMT with a strong, meaningful correlation to all PCOS parameters, making it a reliable marker for the assessment of IR, especially during metformin therapy. Further studies are recommended to promote the application in practice.

Arterial stiffness measured by cardio-ankle vascular index is greater in non-obese young women with polycystic ovarian syndrome

AIM

The association of metabolic abnormalities and polycystic ovarian syndrome (PCOS) has been documented, but few studies have focused on cardiovascular risk in these women. The aim of this study was to compare arterial stiffness by using the cardio-ankle vascular index (CAVI) in PCOS women with controls, and to evaluate whether any clinical or laboratory variables had independent associations with it.

METHODS

A group of 160 women, matched for age and body mass index were recruited. Diagnosis of PCOS was made according to the Rotterdam criteria. Arterial stiffness using CAVI was evaluated in non-obese young woman, with and without PCOS.

RESULTS

In the PCOS group (n = 80), 60 cases (75%) had findings of hyperandrogenism, 59 (73.8%) had ovulatory dysfunction, and 70 (87.5%) had an ultrasonographic appearance of polycystic ovaries. Women with PCOS had significantly higher mean CAVI values when compared to subjects without PCOS (5.78 ± 0.64 vs 5.28 ± 0.77, P < 0.001). Multiple regression analysis revealed that androgen excess was associated with increased arterial stiffness, independent of ovulatory dysfunction, polycystic ovaries, body mass index and age.

CONCLUSION

This data suggests that vascular compliance is decreased in young women with PCOS. Androgen excess is independently associated with increased arterial stiffness.

Metformin improves endothelial function and carotid intima media thickness in patients with PCOS

OBJECTIVE

Oral contraceptive pills (OCP) are widely used for treating women with polycystic ovary syndrome (PCOS). Metformin has beneficial effects on insulin resistance and endothelial functions. The aim of this study was to investigate the effects of treatment with drospirenone/ethinyl estradiol (EE) alone or in combination with metformin on the flow-mediated vasodilatation (FMD) and carotid intima media thickness (CIMT) in women with PCOS.

METHODS

Fifty women with PCOS (mean age 23 ± 5) were randomized to oral treatment of OCP alone (n = 25) or an OCP combination with metformin (n = 25) for 6 months. FMD from the brachial artery and CIMT were calculated. The hormonal profile, HOMA-IR score, basal insulin and glucose levels were studied in both groups. Before and after 6 months' treatment, echocardiographic measurements and laboratory tests were also obtained.

RESULTS

After 6 months' treatment we observed a small decrease in FMD in the OCP group (14.9 ± 9.4 versus 14.4 ± 9.9, p = 0.801) and a slight increase in the combination group (14.5 ± 9.1 versus 15.0 ± 8.0, p = 0.715) but neither of them reached significance. CIMT increased in the OCP group (0.048 ± 0.011 to 0.050 ± 0.010 cm, p = 0.433) and decreased slightly in the combination group (0.049 ± 0.012, 0.048 ± 0.011 cm, p = 0.833).

CONCLUSION

We demonstrated that adding metformin to OCP treatment may have beneficial effect on FMD and CIMT that represent vascular function in patients with PCOS. These results suggest that adding metformin to OCP treatment for PCOS could preserve the cardiovascular system and improve it.

The effects of treatment with drospirenone/ethinyl oestradiol alone or in combination with metformin on elastic properties of aorta in women with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is a heterogeneous clinical condition. Oral contraceptive pills (OCPs) have conventionally been the mainstay of treatment for the amelioration of hyperandrogenism and regulation of menstrual cycles in women with PCOS. Metformin has beneficial effects on insulin resistance and endothelial functions. To our knowledge, the effect of metformin/OCP combination treatment on aortic stiffness has not been studied so far.

OBJECTIVE

The aim of this study was to investigate the effects of treatment with drospirenone/ethinyl oestradiol (E/E) alone or in combination with metformin on the elastic properties of the aorta in women with PCOS.

METHODS

Thirty-seven women with PCOS were enrolled in the study. The first treatment arm, which was treated with OCP alone, was described as the OCP group (19 patients, mean age: 23·2 ± 5·4); the other treatment arm, which was treated with OCP and metformin, was described as the combination group (18 patients, mean age: 23·0 ± 4·5). The elastic parameters of the aorta namely 'aortic strain', 'aortic distensibility', 'aortic diameter alteration' and 'aortic stiffness index' were calculated by the appropriate formulae. The hormonal profile, HOMA-IR score, basal insulin and glucose levels were studied in both groups. Before and after 6 months of treatment, echocardiographic measurements and laboratory tests were also obtained.

RESULTS

After 6 months of treatment, significant weight loss and decrease in body mass index (BMI) were observed in the combination group (75·3 ± 13·3 kg to 72·3 ± 13·5 kg and 31·7 ± 7·3 kg/m² vs 30·4 ± 7·3 kg/m², P = 0·001 and P = 0·001, respectively). Conversely in the OCP group, BMI and weight were not significantly different after 6 months of treatment (68·8 ± 18·3 kg to 71·6 ± 21·2 kg and 26·4 ± 6·2 kg/m² to 27·4 ± 6·9 kg/m², P = 0·159 and P = 0·149, respectively). In addition, there were no significant differences in aortic strain, distensibility (7·7 ± 4·2 to 7·8 ± 3·6 and 7·2 ± 4·1 to 7·7 ± 3·6, P = 0·926 and P = 0·593, respectively) and stiffness index in the OCP group (8·8 ± 7·4 to 8·2 ± 6·7, P = 0·772). However, in the combination group, the adjusted values of the aortic stiffness index decreased significantly at the 6 months' follow-up (10·0 ± 1·5 to 6·7 ± 0·3, P = 0·021) and aortic distensibility and strain increased but not significantly (7·0 ± 4·3 to 9·3 ± 3·3 and 6·8 ± 3·9 to 9·4 ± 3·5, P = 0·163 and P = 0·071, respectively) at the 6 months' follow-up.

CONCLUSION

We demonstrated an improvement in the elastic parameters of the aorta by adding metformin to OCP treatment. We suggest that metformin plus OCP treatment may decrease cardiovascular disease risk in women with PCOS.

Recent advances in cardiovascular aspects of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) has been associated with increased cardiovascular risk (CVR) markers, but population studies have not clarified whether there is an increase in cardiovascular morbidity and mortality. Four different PCOS phenotypes resulted from the Rotterdam criteria that may differ in their CVR potential, thus introducing further complexity. This has led to studies using surrogate CVR markers including biomarkers in blood and imaging such as flow-mediated vasodilatation. In PCOS, both peripheral and central insulin resistance (IR) have been shown. Weight loss has been shown to improve IR and visceral fat, while insulin sensitizer therapies with metformin or thiazolidinediones improve IR and endothelial dysfunction. IR is also found in non-alcoholic fatty liver disease that in turn is very common in PCOS; studies have suggested that IR may be improved by treatment with metformin and omega-3 fish oils. PCOS patients have a more dyslipidemic phenotype that is worse in 'classical PCOS' associated with a higher CVR. Studies with atorvastatin and simvastatin have reported a decrease in the lipid parameters and an improvement in CVR indices including IR, but it is unclear whether this is due to their lipid-lowering action or a pleiotropic effect of the statin. In this expert opinion review, the relevant literature published during the last 2 years was considered. It focuses on some recent important data that has emerged while also exposing the gaps that remain in our knowledge that need to be addressed.

Ultrasonographic and laboratory markers of metabolic and cardiovascular disease risk in obese women with polycystic ovary syndrome

OBJECTIVE

To evaluate whether the presence of polycystic ovary syndrome (PCOS) alters multiple ultrasonographic and laboratory markers of metabolic and cardiovascular disease risk in obese women without any other health condition that could interfere with combined oral contraceptive (COC) eligibility criteria.

METHODS

This was a case-control study evaluating 90 obese women (body mass index (BMI) ≥ 30.0 kg/m(2) and < 40 kg/m(2)) aged between 18 and 40 years without any other health condition that could interfere with COC eligibility criteria, of whom 45 had PCOS and 45 were age-matched controls. BMI, waist and hip circumference, arterial blood pressure, fasting insulin and glucose, quantitative insulin sensitivity check index (QUICKI), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, total cholesterol, triglycerides, testosterone, sex hormone-binding globulin, free androgen index (FAI), carotid stiffness index, intima media thickness, flow-mediated dilatation (FMD) of the brachial artery and non-alcoholic fatty liver disease (NAFLD) were assessed.

RESULTS

In women with PCOS, we observed a higher frequency of NAFLD (73.3 vs. 46.7%, P < 0.01) and higher FAI (10.4 vs. 6.8%, P < 0.01). We also observed a trend towards increased insulin levels (10.06 ± 6.66 vs. 7.45 ± 5.88 µIU/mL, P = 0.05), decreased QUICKI (0.36 ± 0.06 vs. 0.39 ± 0.07, P = 0.05) and decreased FMD (7.00 ± 3.87 vs. 8.41 ± 3.79%, P = 0.08). No other significant difference was observed.

CONCLUSIONS

NAFLD is frequent in obese women without any other health condition that could interfere with COC eligibility criteria, especially in those with PCOS. This should be considered when choosing the best contraceptive option.

Early arterial stiffness and inflammatory bio-markers in normotensive polycystic kidney disease patients

BACKGROUND/AIMS

Cardiovascular disease is the main cause of morbidity and mortality in autosomal-dominant polycystic kidney disease (ADPKD) patients. To clarify temporal relationship between ADPKD, hypertension and the loss of renal function, we examined these factors in patients with early-stage ADPKD who did not yet have hypertension.

METHODS

Fifty patients with ADPKD (42% males, 36.6 ± 9.9 years, no blood pressure medication) and 50 healthy controls (44% males, 35.4 ± 6.4 years) were studied cross-sectionally. Pulse wave velocity (PWV), cardiac morphology and function, aortic elastic indexes, estimated glomerular filtration rate (eGFR), 24-hour ambulatory blood pressure, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and highly sensitive C-reactive protein (hs-CRP) were measured in all participants, using conventional methods.

RESULTS

Despite a normal blood pressure, aortic stiffness index and pulse wave velocity values were increased in patients compared to controls (6.8 ± 4.7 vs. 5.1 ± 3.3, p = 0.043 and 9.6 ± 1.3 vs. 5.8 ± 1.1 m/s, p < 0.001). In univariate analysis, IL-6, TNF-α, hs-CRP and eGFR were all significantly correlated with PWV. The independence of these correlations were analyzed in a regression model, and showed PWV to be significantly predicted by IL-6, TNF-α and hs-CRP.

CONCLUSION

Increased arterial stiffness and pulse wave velocity are early manifestations of ADPKD appearing before hypertension or reduced eGFR. However, these vascular abnormalities are related to signs of systemic low grade inflammation, suggesting a common pathophysiological mechanism apparently present also in other vascular diseases but yet to be elucidated.

Circulating vascular progenitor cells and central arterial stiffness in polycystic ovary syndrome

Objective

Subjects with Polycystic ovarian syndrome (PCOS) are at increased risk of Type 2 diabetes mellitus (T2DM). The mechanism of this enhanced risk is unclear. Circulating vascular progenitor cells (VPC) are immature bone marrow derived cells capable of differentiating into mature endothelial cells. VPC number/function and central arterial stiffness predict cardio-metabolic disease in at-risk populations.

Design

We studied VPC and arterial stiffness measures in non-obese PCOS subjects as compared to age and body mass index (BMI) matched healthy controls in a cross–sectional study.

Methods

Fourteen subjects with PCOS and 12 controls of similar age, BMI (all <30 kg/m²) and metabolic profile were studied. VPC number and in vitro function were studied by flow cytometry and tube formation assays respectively. Augmentation index (AIx), a measure of central arterial stiffness, and central (aortic) blood pressures (BP) were measured by applanation tonometry.

Results

Subjects with PCOS had a reduced number, mean±SEM, of circulating CD34⁺133⁺ VPCs (317.5±51.0 vs. 558.3±101.2, p = 0.03) and impaired in vitro tube formation (completed tube area 1.0±0.06 vs. 1.2±0.05×10⁶ µm² p = 0.02). PCOS subjects had significantly higher AIx (18.4±1.9% vs. 4.9±2.0%) and this difference remained significant even after adjustments for age, BMI and smoking (p = 0.003) in multivariate analyses. Central systolic and pulse pressure were higher in PCOS subjects but these differences were not statistically significant after adjustment for age. Brachial systolic and pulse pressures were similar. VPC number/function and arterial stiffness or BP measures were not correlated.

Conclusions

Non-obese PCOS is characterized by a reduced VPC number, impaired VPC function and increased central arterial stiffness. These changes in novel vascular risk markers may explain the enhanced risk of T2DM and CVD in PCOS.