Increases in central fat mass and decreases in peripheral fat mass are associated with accelerated arterial stiffening in healthy adults: the Amsterdam Growth and Health Longitudinal Study

Lower Lean Mass Is Associated with Greater Arterial Stiffness in Patients with Lower Extremity Artery Disease

Background: Arterial stiffness is independently associated with lower extremity artery disease (LEAD). Although obesity is already known as an independent cardiovascular risk factor, it was found that, paradoxically, in patients diagnosed with cardiovascular disease, an increase in body mass index (BMI) was associated with a decrease in mortality. However, the underlying mechanism of this paradoxical association remain uncertain. In this study, we firstly hypothesize that arterial stiffness correlates with body mass; secondly, the underlying mechanism of the association for patients with LEAD is individual body composition, in particular, lean mass. Methods: The present study was performed as a single-center, prospective, observational analysis. A total of 412 patients with current or previously diagnosed LEAD (Rutherford Classification 2–4) were included, the cfPWV and AIx were measured as indices of arterial stiffness, and a body composition assessment was performed. Results: In male patients, there was a significantly negative correlation between the AIx and lean mass coefficient (p = 0.004, 95% CI: −0.28 (−0.48–0.09)). Conclusion: For patients with peripheral arterial disease, our data show that lower lean mass in male patients is associated with increased arterial stiffness as measured by the AIx. Therefore, progressive resistance training may be beneficial for the reduction in arterial stiffness in PAD patients in secondary prevention.

Association of Body Composition with Arterial Stiffness in Long-lived People

Fundamento

Pouco se conhece sobre a relação entre sarcopenia e hemodinâmica central em idosos longevos.

Objetivo

Estudar a relação da rigidez arterial com a composição corporal em idosos longevos.

Métodos

A composição corporal foi avaliada por meio da absortometria de Raio X de dupla energia (DEXA) e dos parâmetros de circulação central (PCC) obtidos por método oscilométrico não invasivo, com o Mobil-O-Graph 24h PWA Monitor®. Os parâmetros centrais avaliados foram: velocidade da onda de pulso (VOP), augmentation index (AIx), índice de amplificação da pressão de pulso (iAPP) e pressão de pulso central (PPc). Estes foram correlacionados com massa magra total (MM) e apendicular (MA), percentual de gordura corporal e índice de Baumgartner (IB). Aceitou-se nível de significância de 5%.

Resultados

Participaram 124 longevos, com idade média de 87,1 anos (DP±4,3 anos), sendo 74,2% mulheres e 57,3% brancos. Houve correlação inversa do AIx com as variáveis MM (r = - 0,391, p < 0,001), MA (r= -0,378, p< 0,001) e IB (r = -0,258, p 0,004). A PPc apresentou associação inversa com MM (r= -0,268, p =0,003), MA (r=-0,288, p= 0,001) e IB (r= -0,265, p = 0,003). Houve relação direta apenas entre AIx e percentual de gordura corporal (r= 0,197, p= 0,029).

Conclusão

Em idosos longevos, o percentual de gordura corporal se associa diretamente com a rigidez arterial e tem associação inversa com a quantidade de MM. Esses achados podem estar associados ao maior risco cardiovascular.

Carotid artery intima-media thickness in adults receiving long-term home parenteral nutrition

BACKGROUND AND AIMS

Nutrition regimen in parenteral nutrition (PN) patients allows for a control of diet components. This may affect the process of lipid deposition in the vascular wall and change the risk of atherosclerosis. This study aims to examine the effect of long-term PN in adults on carotid intima-media thickness.

METHODS AND RESULTS

Thirty long-term PN patients (15 men and 15 women, mean age 64.7 ± 8.5 years) and thirty healthy volunteers (HV) (15 men and 15 women, mean age 64.9 ± 8.77 years) entered the study. Total amino acid and lipid formulation intake as well as duration of PN were calculated for PN patients. The common carotid artery intima-media thickness (CCA IMT) was examined in both groups. A lower CCA IMT (right/left mean: PN - 776 ± 121 vs HV - 848 ± 121 μm, p < 0.05; right/left maximum CCA IMT: PN - 935 ± 139 vs HV - 1024 ± 135 μm, p < 0.05) in PN patients was observed. A lower serum level of total (PN - 131.43 ± 43.12 vs HV - 209.2 ± 48.01 mg/dl, p < 0.05) and HDL (PN- 44.16 ± 12.45 vs HV - 72.57 ± 25.04 mg/dl, p < 0.05) cholesterol was reported in the PN patients. A correlation between patients' age and CCA IMT was observed in the control group, but not in the PN patients (right/left mean CCA IMT - PN: r = 0.48, p-0.007 vs HV: p-0.073; right/left maximum CCA IMT - PN: r = 0.48, p-0.008, vs HV: p-0.073).

CONCLUSIONS

Long term PN in adults is associated with lower CCA IMT. Long-term PN patients are a unique group in which carotid intima-media thickness does not correlate with the age.

Peripheral fat distribution versus waist circumference for predicting mortality in metabolic syndrome

OBJECTIVE

To elucidate whether the peripheral fat (PF)-combined definition of metabolic syndrome (MetS) would show a better predictive ability for cause-specific mortality than the common MetS.

METHODS

Data were derived from the National Health and Nutrition Examination Survey from 1999 through 2002. We investigated three types of MetS including waist circumference MetS (WCMetS), PFMetS, and PF-combined definition of MetS. The main outcome was to evaluate the predictive ability of the newly defined MetS for time to cause-specific mortality. The secondary outcomes were the relationships between the PF percentage and C-reactive protein (CRP) and homeostasis model assessment of insulin resistance (HOMA-IR) to clarify the gender discrepancy.

RESULTS

For cardiovascular mortality, the adjusted hazard ratios for WCMetS, PFMetS, and PF-combined definition MetS were 1.867, 1.742, and 2.117, respectively (all P < 0.001). A positive association between PF percentage and CRP in men and a negative correlation between PF percentage and HOMA-IR in women after adjustment for all variates were found.

CONCLUSIONS

The PF-combined definition of MetS had a stronger predictive ability for all-cause and cardiovascular mortality than general MetS. Notably, the PF might have differential gender-specific health effects on cardiovascular events.

Relation between age and carotid artery intima-medial thickness: a systematic review

Carotid artery intima-medial thickness (cIMT) represents a popular measure of atherosclerosis and is predictive of future cardiovascular and cerebrovascular events. Although older age is associated with a higher cIMT, little is known about whether this increase in cIMT follows a linear relationship with age or it is affected under influence of cardiovascular diseases (CVD) or CVD risk factors. We hypothesize that the relationship between cIMT and age is nonlinear and is affected by CVD or risk factors. A systematic review of studies that examined cIMT in the general population and human populations free from CVD/risk factors was undertaken. The literature search was conducted in PubMed, Scopus, and Web of Science. Seventeen studies with 32 unique study populations, involving 10,124 healthy individuals free from CVD risk factors, were included. Furthermore, 58 studies with 115 unique study populations were included, involving 65,774 individuals from the general population (with and without CVD risk factors). A strong positive association was evident between age and cIMT in the healthy population, demonstrating a gradual, linear increase in cIMT that did not differ between age decades (r = 0.91, P < 0.001). Although populations with individuals with CVD demonstrated a higher cIMT compared to populations free of CVD, a linear relation between age and cIMT was also present in this population. Our data suggest that cIMT is strongly and linearly related to age. This linear relationship was not affected by CVD or risk factors.

The Hierarchy of Brain Networks Is Related to Insulin Growth Factor-1 in a Large, Middle-Aged, Healthy Cohort: An Exploratory Magnetoencephalography Study

Recently, a large study demonstrated that lower serum levels of insulin growth factor-1 (IGF-1) relate to brain atrophy and to a greater risk for developing Alzheimer's disease in a healthy elderly population. We set out to test if functional brain networks relate to IGF-1 levels in the middle aged. Hence, we studied the association between IGF-1 and magnetoencephalography-based functional network characteristics in a middle-aged population. The functional connections between brain areas were estimated for six frequency bands (delta, theta, alpha1, alpha2, beta, gamma) using the phase lag index. Subsequently, the topology of the frequency-specific functional networks was characterized using the minimum spanning tree. Our results showed that lower levels of serum IGF-1 relate to a globally less integrated functional network in the beta and theta band. The associations remained significant when correcting for gender and systemic effects of IGF-1 that might indirectly affect the brain. The value of this exploratory study is the demonstration that lower levels of IGF-1 are associated with brain network topology in the middle aged.

Conventional and Ambulatory Blood Pressure as Predictors of Diastolic Left Ventricular Function in a Flemish Population

Background

No longitudinal study compared associations of echocardiographic indexes of diastolic left ventricular function studies with conventional (CBP) and daytime ambulatory (ABP) blood pressure in the general population.

Methods and Results

In 780 Flemish (mean age, 50.2 years; 51.7% women), we measured left atrial volume index (LAVI), peak velocities of the transmitral blood flow (E) and mitral annular movement (e′) in early diastole and E/e′ 9.6 years (median) after CBP and ABP. In adjusted models including CBP and ABP, we expressed associations per 10/5‐mm Hg systolic/diastolic blood pressure increments. LAVI and E/e′ were 0.65/0.40 mL/m² and 0.17/0.09 greater with higher systolic/diastolic ABP (P≤0.028), but not with higher baseline CBP (P≥0.086). e′ was lower (P≤0.032) with higher diastolic CBP (−0.09 cm/s) and ABP (−0.19 cm/s). When we substituted baseline CBP by CBP recorded concurrently with echocardiography, LAVI and E/e′ remained 0.45/0.38 mL/m² and 0.15/0.08 greater with baseline ABP (P≤0.036), while LAVI (+0.53 mL/m²) and E/e′ (+0.19) were also greater (P<0.001) in relation to concurrent systolic CBP. In categorized analyses of baseline data, sustained hypertension or masked hypertension compared with normotension or white‐coat hypertension was associated with greater LAVI (24.0 versus 22.6 mL/m²) and E/e′ (7.35 versus 6.91) and lower e′ (10.7 versus 11.6 cm/s; P≤0.006 for all) with no differences (P≥0.092) between normotension and white‐coat hypertension or between masked hypertension and sustained hypertension.

Conclusions

ABP is a long‐term predictor of diastolic left ventricular function, statistically outperforming distant but not concurrent CBP. Masked hypertension and sustained hypertension carry equal risk for deterioration of diastolic left ventricular function.

Upper and lower limbs composition: a comparison between anthropometry and dual-energy X-ray absorptiometry in healthy people

The detection of changes in lean mass (LM) distribution can help to prevent disability. This study assessed the degree of association between anthropometric measurements and dual-energy X-ray absorptiometry (DXA) body composition (BC) parameters of the upper and lower limbs in a healthy general population and collected DXA age- and sex-specific values of BC that can be useful to build a reference standard.

PURPOSE

The primary aim of this study was to investigate the reliability of some widely available anthropometric measurements in the assessment of body composition (BC) at the limbs, especially in terms of muscle mass, in a large sample of healthy subjects of different age bands and sex, using fat mass (FM) and lean mass (LM) parameters derived by dual-energy X-ray absorptiometry (DXA) as the gold standard. The secondary aim was to collect DXA age- and sex-specific values of BC of left and right limbs (upper and lower) in a healthy Italian population to be used as reference standards.

METHODS

Two hundred fifty healthy volunteers were enrolled. Arm circumference (AC) and thigh circumference (ThC) were measured, and total and regional BC parameters were obtained by a whole-body DXA scan (Lunar iDXA, Madison, WI, USA; enCORE™ 2011 software version 13.6).

RESULTS

FM/LM showed only fair correlation with AC and ThC in females (r = 0.649 and 0.532, respectively); in males and in the total population, the correlation was low (r = 0.360 or lower, and p non-statistically significant). AC and ThC were not well representative of arms LM in both genders (females r = 0.452, males r = 0.530) independently of age. In general, men of all age groups showed higher values of LM and lean mass index (LMI) in both total and segmental upper and lower limbs. In males, the maximum LM and LMI were achieved in the fifth decade in both upper and lower limbs and then started to decrease with aging. In females, no significant modification with aging was identified in LM and LMI.

CONCLUSION

According to our results, anthropometry is not well representative of LM of arms in both genders, independently of age; therefore, a densitometric examination should be considered for a correct assessment of BC at limbs.

Relation between carotid stiffness, cognitive performance and brain connectivity in a healthy middle-aged population: an observational neurophysiological cohort study with magnetoencephalography

OBJECTIVE

Impaired blood flow of the carotid artery can result in cognitive impairment, but how these vascular impairments lead to global cognitive disturbances is largely unknown. Problems in functional connectivity between brain areas may be responsible for these widespread effects. Therefore, the aim of this study was to examine the association between carotid stiffness, functional connectivity and cognitive performance in relatively young and healthy adults before clinical vascular pathology occurs.

DESIGN

The Amsterdam Growth and Health Longitudinal Study: an observational study.

SETTING

Participants were included by attending 1 of the 2 selected secondary schools in The Netherlands.

PARTICIPANTS

Men (n=110) and women (n=120) aged 41-44 years (42±0.7).

PRIMARY AND SECONDARY OUTCOME MEASURES

Data were obtained with regard to local carotid stiffness captured measured with the Young's elastic modulus (YEM). All participants underwent a commonly used Dutch intelligence test and resting-state eyes-closed magnetoencephalography (MEG). Five artefact-free epochs were analysed. The phase lag index (PLI) was used as a measure of functional connectivity between all sensors and was assessed in six frequency bands (δ-γ).

RESULTS

Carotid stiffness was significantly associated with increased functional connectivity in the α2 band in men (β: 0.287; p=0.008). The same results were found for women in the β band (β: 0.216; p=0.040). Furthermore, carotid stiffness was associated with superior cognitive function in men (β: 0.238; p=0.007). In addition, there was neither a significant association nor a consistent pattern between cognitive function and functional connectivity.

CONCLUSIONS

The increased connectivity might be a maladaptive phenomenon caused by disinhibition of neurons which may explain the direction of the results. This study suggests that detection of increased (local) carotid stiffness may be promising to identify a disturbance in the organisation of the functional brain network, even before clinical vascular pathology occurs.

Neck circumference is associated with carotid intimal-media thickness but not with coronary artery calcium: Results from The ELSA-Brasil

BACKGROUND AND AIMS

It is uncertain whether neck circumference can be a risk indicator for subclinical atherosclerosis. We aimed to investigate their relationships measured by coronary artery calcium (CAC) and common carotid intima-media thickness (cc-IMT) with neck circumference in ELSA-Brasil.

METHODS AND RESULTS

In cross-sectional and sex-specific analyses of 2266 women (50.6 ± 8.4 yrs) and 1886 men (50.7 ± 9.0 yrs) with both cc-IMT and CAC, free from previous cardiovascular disease at baseline, we built logistic models using diverse cut-off points for CAC score (0 vs > 0, < 100 vs ≥ 100, < 400 vs ≥ 400 Agatston units) and cc-IMT (< 75 th percentile vs ≥ 75 th; <90th percentile vs ≥ 90 th) as dependent variables, after which adjustments for age and traditional cardiovascular risk factors were made. Mean neck circumference was 33.6 (± 2.4 cm) for women and 38.8 (± 2.6 cm) for men. In fully adjusted models including sociodemographic, cardiovascular risk factors and body-mass index and waist circumference, for each 1 standard deviation increase in neck circumference we found an odds ratio (OR, 95% CI) for IMT above the 75th percentile of (1.52, 1.16; 1.99) for women and (1.66, 1.28; 2.14) for men, and above the 90th cc-IMT percentile [1.66 (1.19; 2.32) for men but not for women [1.21 (0.80; 1.82)]. We found no association between neck circumference and CAC using different cut-off points (p > 0.05 for all).

CONCLUSION

Neck circumference was significantly and independently associated with cc-IMT but not with CAC in women and men, indicating a possible effect of perivascular fat tissue on atherosclerosis.

Assessment of Arterial Stiffness, Volume, and Nutritional Status in Stable Renal Transplant Recipients

Reduction of cardiovascular death might have a significant effect on the long-term survival rates of renal transplant recipients (RTRs). The aim of the study was to assess the relation between arterial stiffness and graft function, adipose tissue content, and hydration status in patients after kidney transplantation (KTx).The study included 83 RTR patients (mean age: 55 ± 13 years) who had been admitted to a nephrology-transplantation outpatient clinic 0.5 to 24 years after KTx. Clinical and laboratory data were analyzed and eGFR was calculated with the CKD-EPI formula. Arterial stiffness was assessed in all RTRs with pulse wave propagation velocity (PWV) with the use of a complior device. In addition, fluid and nutritional status was assessed with a Tanita BC 418 body composition analyzer. The control group consisted of 31 hospital workers who received no medication and had no history of cardiovascular disease.Multivariable linear regression analysis, with PWV as a dependent variable, retained the following independent predictors in the final regression model: red blood cell distribution width (RDW) (B = 0.323; P = 0.004), age (B = 0.297; P = 0.005), tacrolimus therapy (B = -0.286; P = 0.004), and central DBP (B = 0.185; P = 0.041). Multivariable linear regression analysis with eGFR as a dependent variable retained the following independent predictors in the final regression model; creatinine concentration (B = -0.632; P = 0.000), hemoglobin (B = 0.280; P = 0.000), CRP (B = -0.172; P = 0.011), tacrolimus therapy (B = 0.142; P = 0.039), and triglycerides (B = -0.142; P = 0.035).Our data indicates that: kidney transplant recipients can present modifiable CVD risk factors linked to increased arterial stiffness, DBP, waist circumference, SCr, time on dialysis, CyA therapy, and visceral fat mass; RDW is a parameter associated with arterial stiffness; and parameters such as CyA therapy, time on dialysis, PWV, RDW, and triglycerides show negative associations with the allograft function assessed with eGFR.

Intramyocellular and Extramyocellular Lipids Are Associated With Arterial Stiffness

BACKGROUND

Obese and overweight patients are at increased risk of arterial stiffness, and visceral, epicardial and hepatic fat accumulation is associated with cardiovascular disease risk. In general, muscular lipids are stored either in interstitial adipose tissue (extramyocellular lipid (EMCL)) or in lipid droplets within muscle cells (intramyocellular lipid (IMCL)). However, the association between IMCL or EMCL content and arterial stiffness remains unclear. This cross-sectional study aimed to clarify this association.

METHODS

A total of 237 subjects (18-81 years) were enrolled in this study. The IMCL and EMCL contents of the right vastus lateralis muscle were evaluated by proton magnetic resonance spectroscopy. Arterial stiffness was estimated using brachial-ankle pulse wave velocity (baPWV).

RESULTS

There were significant correlations between baPWV and the contents of both IMCL (R = -0.23, P < 0.001) and EMCL (R = 0.53, P < 0.001) in all subjects. The baPWV negatively correlated with IMCL content (R = -0.45, P < 0.001) in females only. In contrast, significant positive correlations were observed between baPWV and EMCL content in both males (R = 0.59, P < 0.001) and females (R = 0.55, P < 0.001). IMCL and EMCL contents contributed independently to baPWV variation after adjustment for age, sex, body mass index, visceral and subcutaneous abdominal fat, upper and lower limb fat, blood pressure, heart rate, and lipid profiles.

CONCLUSION

These results suggest that IMCL and EMCL contents may be a risk factor for arterial stiffness, and this association differed with gender and age.

The relationship between 30-year developmental patterns of body fat and body fat distribution and its vascular properties: the Amsterdam Growth and Health Longitudinal Study

Introduction:

Although body fat and body fat distribution are known to be related to cardiovascular diseases (CVDs), it is unknown whether specific 30-year developmental patterns of body fat are associated with CVDs. This study examines the existence of distinct developmental patterns of total fat measured by the sum of four skinfolds (S4SFs) and body fat distribution measured by the skinfold thickness ratio (SFratio), and relates these patterns to micro- and macrovascular functions.

Methods:

In 2006, 259 apparently healthy subjects were examined on micro- and macrovascular functions, using video microscopy and carotid ultrasound sonography. Body fat, using both S4SFs and SFratio, was measured for 10 times over 30 years, from 13 years onwards. Latent class growth analyses (LCGA) were used to obtain distinct developmental patterns of S4SFs and SFratio. This is a data-drive hypothesis-generating approach and could possibly give a new perspective on body fatness over time. In addition, a mixed-method approach is used to obtain individual growth parameters. Linear regression analyses were used to examine the relationship of these patterns and individual growth parameters with micro- and macrovascular functions.

Results:

LCGA identified normal and unfavourable developmental patterns in S4SFs and SFratio. Both men and women with an unfavourable developmental pattern of S4SFs showed impaired carotid compliance (β=−0.216, P=0.004 and β=−0.109, P=0.039, respectively), carotid distensibility (β=−5.078, P=0.001 and β=−5.118, P<0.001, respectively) and Young's elastic modulus (β=0.066, P=0.065 and β=0.107, P<0.001, respectively). In contrast, no relationship for microvascular function with developmental patterns of S4SFs was found. Developmental patterns of the SFratio were associated with neither measures of micro- nor macrovascular functions. No associations were using the individual growth parameters.

Conclusions:

For macrovascular function, there is a relationship of 30-year developmental patterns of S4SFs, whereas no such relationship was found for the 30-year developmental patterns of S4SFs or SFratio with microvascular function.

Assessment of volume status and arterial stiffness in chronic kidney disease

AIM

There is limited information about arterial stiffness in chronic kidney disease (CKD) which is an independent risk factor for cardiovascular events. Pulse wave velocity (PWV), augmentation index (AIx) are using to determine arterial stiffness. We aimed to study PWV, AIx, volume status in patients with stage 3B-5 CKD and continuous ambulatory peritoneal dialysis (CAPD).

METHODS

Sixty-six stage 3B-5 CKD patients, 21 CAPD patients, 34 healthy controls were included. Pulse wave velocity, AIx, volume status was evaluated by Mobil-O-Graph®, and bioimpedance spectroscopy, respectively.

RESULTS

The Median PWV was 7.5 m/s in CKD, 6.2 m/s in CAPD, 5.9 m/s in healthy controls, and while PWV was found to have increased significantly in CKD patients (p = 0.002), the Alx values were similar in all groups. The median extracellular fluid excess was higher in both the CKD and, CAPD patients when compared with healthy controls (1.26 and 1.21 L, respectively). Overhydration was more prevalent in CKD and CAPD patients (p < 0.001). Age, central systolic blood pressure, body mass index, fat mass, overhydration, CKD, eGFR were the major determinants of PWV.

CONCLUSION

Increased PWV was found in stage 3B-5 CKD patients. Overhydration may contribute this increment.

Ectopic fat and cardiometabolic and vascular risk

Given that the variation in how regional adipose tissue handles and stores excess dietary energy has substantial cardiometabolic implications, ectopic fat distribution might be an important predictor of cardiometabolic and vascular risk, in addition to overall obesity itself. Conceptually, ectopic fat depots may be divided into systemically acting fat depots and locally acting fat depots. Systemically acting fat depots include visceral fat, fat in the liver, muscle, or neck, and subcutaneous fat. Accumulation in the abdominal visceral area, compared with overall obesity, has an equally or more important role in the development of cardiometabolic risk. Fat depots in liver/muscle tissue cause adverse cardiometabolic effects by affecting energy metabolism. Fat depots in lower-body subcutaneous areas may be protective regarding cardiometabolic risk, by trapping remnant energy. Fat accumulation in the neck is a unique type of fat depot that may increase cardiovascular risk by increasing insulin resistance. Locally acting fat depots include pericardial fat, perivascular fat, and renal sinus fat. These fat depots have effects primarily on adjacent anatomic organs, directly via lipotoxicity and indirectly via cytokine secretion. Pericardial fat is associated with coronary atherosclerosis. Perivascular fat may play an independent role in adverse vascular biology, including arterial stiffness. Renal sinus fat is a unique fat depot that may confer additional cardiometabolic risk. Thus, ectopic fat depots may contribute to the understanding of the link between body composition and cardiometabolic risk. In this review, we focus on the role and clinical implications of ectopic fat depots in cardiometabolic and vascular risk.

Negative association between trunk fat, insulin resistance and skeleton in obese women

AIM

To evaluate the potential interference of trunk fat (TF) mass on metabolic and skeletal metabolism.

METHODS

In this cross-sectional study, 340 obese women (mean age: 44.8 ± 14 years; body mass index: 36.0 ± 5.9 kg/m(2)) were included. Patients were evaluated for serum vitamin D, osteocalcin (OSCA), inflammatory markers, lipids, glucose and insulin (homeostasis model assessment of insulin resistance, HOMA-IR) levels, and hormones profile. Moreover, all patients underwent measurements of bone mineral density (BMD; at lumbar and hip site) and body composition (lean mass, total and trunk fat mass) by dual-energy X-ray absorptiometry.

RESULTS

Data showed that: (1) high TF mass was inversely correlated with low BMD both at lumbar (P < 0.001) and hip (P < 0.01) sites and with serum vitamin D (P < 0.0005), OSCA (P < 0.0001) and insulin-like growth factor-1 (IGF-1; P < 0.0001) levels; (2) a positive correlation was found between TF and HOMA-IR (P < 0.01), fibrinogen (P < 0.0001) and erythrocyte sedimentation rate (P < 0.0001); (3) vitamin D levels were directly correlated with IGF-1 (P < 0.0005), lumbar (P < 0.006) and hip (P < 0.01) BMD; and (4) inversely with HOMA-IR (P < 0.001) and fibrinogen (P < 0.0005).Multivariate analysis demonstrated that only vitamin D was independent of TF variable.

CONCLUSION

In obese women, TF negatively correlates with BMD independently from vitamin D levels. Reduced IGF-1 and increased inflammatory markers might be some important determinants that account for this relationship.

Reference intervals for common carotid intima-media thickness measured with echotracking: relation with risk factors

AIMS

Common carotid artery intima-media thickness (CCIMT) is widely used as a surrogate marker of atherosclerosis, given its predictive association with cardiovascular disease (CVD). The interpretation of CCIMT values has been hampered by the absence of reference values, however. We therefore aimed to establish reference intervals of CCIMT, obtained using the probably most accurate method at present (i.e. echotracking), to help interpretation of these measures.

METHODS AND RESULTS

We combined CCIMT data obtained by echotracking on 24 871 individuals (53% men; age range 15-101 years) from 24 research centres worldwide. Individuals without CVD, cardiovascular risk factors (CV-RFs), and BP-, lipid-, and/or glucose-lowering medication constituted a healthy sub-population (n = 4234) used to establish sex-specific equations for percentiles of CCIMT across age. With these equations, we generated CCIMT Z-scores in different reference sub-populations, thereby allowing for a standardized comparison between observed and predicted ('normal') values from individuals of the same age and sex. In the sub-population without CVD and treatment (n = 14 609), and in men and women, respectively, CCIMT Z-scores were independently associated with systolic blood pressure [standardized βs 0.19 (95% CI: 0.16-0.22) and 0.18 (0.15-0.21)], smoking [0.25 (0.19-0.31) and 0.11 (0.04-0.18)], diabetes [0.19 (0.05-0.33) and 0.19 (0.02-0.36)], total-to-HDL cholesterol ratio [0.07 (0.04-0.10) and 0.05 (0.02-0.09)], and body mass index [0.14 (0.12-0.17) and 0.07 (0.04-0.10)].

CONCLUSION

We estimated age- and sex-specific percentiles of CCIMT in a healthy population and assessed the association of CV-RFs with CCIMT Z-scores, which enables comparison of IMT values for (patient) groups with different cardiovascular risk profiles, helping interpretation of such measures obtained both in research and clinical settings.

Clustering of metabolic syndrome traits is associated with maladaptive carotid remodeling and stiffening: a 6-year longitudinal study

Maladaptive arterial remodeling may constitute a mechanism underlying the risk of stroke in individuals with the metabolic syndrome (MetS), but evidence supporting this contention derives from cross-sectional studies only. We, therefore, investigated, in apparently healthy adults, whether changes in MetS status between the ages of 36 and 42 years (never [n=207, reference group], incident [n=31], recovery [n=23], and persistent [n=32]) were associated with changes in carotid interadventitial diameter, lumen diameter, intima-media thickness, circumferential wall tension and stress, and Young's elastic modulus. All data analyses were adjusted for sex, height, and (changes in) age, lifestyle variables, low-density lipoprotein cholesterol, and use of antihypertensive medication. At baseline and as compared with the reference group, individuals with persistent MetS had significantly higher interadventitial diameter, circumferential wall tension, circumferential wall stress, and Young's elastic modulus but not intima-media thickness. In the course of follow-up, these individuals (versus reference group) displayed significantly steeper increases in intima-media thickness (0.011 versus 0.005 mm/y), which were accompanied by significantly steeper increases in interadventitial diameter (0.077 versus 0.032 mm/y) and lumen diameter (0.055 versus 0.023 mm/y) but not circumferential wall stress, which decreased (-0.34 versus 0.12 kPa/y). These findings suggest that increases in intima-media thickness in young adults with the MetS may primarily reflect an adaptive mechanism that attempts to restore local hemodynamic conditions to an equilibrium rather than atherosclerosis, per se. However, carotid adaptations did not restore circumferential wall stress to levels comparable with those of the reference group, and, therefore, outward remodeling was maladaptive. Importantly, individuals who recovered from the MetS restored carotid properties to levels comparable to the reference group, emphasizing the potential for reversibility.

Cohort profile: the Amsterdam Growth and Health Longitudinal Study

The Amsterdam Growth and Health Longitudinal Study (AGHLS) is a unique, multidisciplinary cohort study that was initially set up to examine growth and health among teenagers. Throughout the years, the AGHLS has aimed to answer research questions dealing with the relationships between the (natural) development of anthropometry, lifestyle and health from adolescence into adulthood. The AGHLS specifically focuses on anthropometrics, physical activity and fitness, cardiovascular disease risk, lifestyle, musculoskeletal health, psychological health and well-being. Besides this, many methodological issues related to the analysis of longitudinal data were also explored within the framework of the AGHLS. In 1976, students from two secondary schools from the greater Amsterdam area were included in the study. Between 1976 and 2006, 10 rounds of measurement were performed covering an age range between 13 and 43 years. The huge database collected so far has been primarily used to answer relevant research questions regarding the longitudinal relationship between lifestyle and health. Further information about the study can be obtained from the principal investigator Jos Twisk (jwr.twisk@vumc.nl), and up-to-date information on AGHLS can be found by visiting the website www.aggo.nl.

Carotid stiffness in young adults: a life-course analysis of its early determinants: the Amsterdam Growth and Health Longitudinal Study

Cardiovascular risk factors affecting arterial stiffness in adulthood may develop at different critical periods earlier in life. We examined whether the trajectories, from adolescence to young adulthood, of blood pressure, body fatness and fat distribution, blood lipids, cardiorespiratory fitness, and heart rate determined levels of arterial stiffness in young adults. We investigated 373 apparently healthy adults in whom cardiovascular risk factors were repeatedly examined between the ages of 13 and 36 years and carotid stiffness estimates were obtained at the age of 36 years. Differences in the mean levels and the trajectories of risk factors throughout the 24-year longitudinal period between subjects with different levels of carotid stiffness at age 36 years were analyzed with generalized estimating equations. Compared with individuals with less stiff carotid arteries, those with stiffer carotid arteries at the age of 36 years were characterized from ages 13 to 36 years by greater levels of and steeper increases in blood pressure and central fatness, independently of each other and other risk factors. These increases were already present in adolescence, preceded the development of poorer levels of blood lipids, cardiorespiratory fitness, and heart rate, which were evident during adulthood only, and explained to a great extent the deleterious association between these risk factors and carotid stiffness at the age of 36 years. Multiple and intertwined mechanisms involved in the pathogenesis of arterial stiffness have their origins in early life. Blood pressure and central fatness have a pivotal role herein and should be specifically targeted to prevent arterial stiffening and its cardiovascular sequelae.

Endothelial Dysfunction and Low-Grade Inflammation Are Associated With Greater Arterial Stiffness Over a 6-Year Period

Endothelial dysfunction and low-grade inflammation are associated with cardiovascular disease. Arterial stiffening plays an important role in cardiovascular disease and, thus, may be a mechanism through which endothelial dysfunction and/or low-grade inflammation lead to cardiovascular disease. We investigated the associations between, on the one hand, biomarkers of endothelial dysfunction (soluble endothelial selectin, thrombomodulin, and both vascular and intercellular adhesion molecules 1 and von Willebrand factor) and of low-grade inflammation (C-reactive protein, serum amyloid A, interleukin 6, interleukin 8, tumor necrosis factor-α and, soluble intercellular adhesion molecule 1) and, on the other hand, arterial stiffness over a 6-year period, in 293 healthy adults (155 women). Biomarkers were combined into mean z scores. Carotid, femoral, and brachial arterial stiffness and carotid-femoral pulse wave velocity were determined by ultrasonography. Measurements were obtained when individuals were 36 and 42 years of age. Associations were analyzed with generalized estimating equation and adjusted for sex, height, and mean arterial pressure. The endothelial dysfunction z score was inversely associated with femoral distensibility (β: −0.51 [95% CI: −0.95 to −0.06]) and compliance coefficients (β: −0.041 [95% CI: −0.076 to −0.006]) but not with carotid or brachial stiffness or carotid-femoral pulse wave velocity. The low-grade inflammation z score was inversely associated with femoral distensibility (β: −0.51 [95% CI: −0.95 to −0.07]) and compliance coefficients (β: −0.050 [95% CI: −0.084 to −0.016]) and with carotid distensibility coefficient (β: −0.910 [95% CI: −1.810 to −0.008]) but not with brachial stiffness or carotid-femoral pulse wave velocity. Biomarkers of endothelial dysfunction and low-grade inflammation are associated with greater arterial stiffness. This provides evidence that arterial stiffening may be a mechanism through which endothelial dysfunction and low-grade inflammation lead to cardiovascular disease.