S. Avallone

Diagnostic criteria for metabolic syndrome: a comparative analysis in an unselected sample of adult male population

This analysis compares the performance of 7 different diagnostic criteria of metabolic syndrome (MS) with regard to the prevalence of the syndrome, the characteristics of subjects with a positive diagnosis, and the ability to correctly identify individuals at high calculated cardiovascular (CV) risk or with signs of systemic inflammation or early organ damage. The diagnostic criteria proposed by the World Health Organization (1998); European Group for the Study of Insulin Resistance (EGIR) (1999); Adult Treatment Panel III (ATP III) (2001); American Association of Clinical Endocrinologists (AACE) (2003); ATP III (2004); International Diabetes Federation (IDF) (2005); and American Heart Association/National Heart, Lung, and Blood Institute (2005) were applied to the population of 933 men aged 59.5 years (range, 33-81 years) attending the 2002-2004 examination of the Olivetti Heart Study. Standardized measurements were available for body mass index, waist circumference, blood pressure, fasting serum total and high-density lipoprotein cholesterol, triglyceride, glucose, insulin, high-sensitivity C-reactive protein, and microalbuminuria. Insulin resistance was estimated by the homeostasis model assessment index; and CV risk, by the Prospective Cardiovascular Munster algorithm. The MS prevalence ranged from 8.6% (AACE) to 44.5% (IDF). Among MS-positive subjects, insulin resistance ranged from 94.8% (EGIR) to 49.2% (IDF), whereas type 2 diabetes mellitus (excluded by EGIR and AACE criteria) rated 59.9% by World Health Organization and 22% to 24% by ATP III, IDF, or American Heart Association/National Heart, Lung, and Blood Institute. By most criteria, MS-positive subjects had greater calculated CV risk than MS-negative subjects; but in general, the ability to correctly identify individuals at high CV risk was dampened by limited sensitivity (maximum 60%). Lowering the cutoff for abdominal adiposity (waist circumference <94 cm by IDF) did not improve the performance in this regard but identified a larger number of individuals with microalbuminuria (56%) and elevated C-reactive protein (53%).

High Sodium and Low Potassium Intake among Italian Children: Relationship with Age, Body Mass and Blood Pressure

Background Hypertension is the leading cause of death in developed countries and reduction of salt intake is recommended as a key preventive measure. Objective To assess the dietary sodium and potassium intakes in a national sample of Italian children and adolescents and to examine their relationships with BMI and blood pressure (BP) in the framework of the MINISAL survey, a program supported by the Italian Ministry of Health. Population and Methods The study population included 1424 healthy subjects (766 boys, 658 girls) aged 6-18 years (mean age: 10.1±2.9) who were consecutively recruited in participating National Health Service centers in 10 Italian regions. Electrolyte intake was estimated from 24 hour urine collections tested for completeness by the concomitant measurement of creatinine content. Anthropometric indices and BP were measured with standardized procedures. Results The average estimated sodium intake was 129 mmol (7.4 g of salt) per day among boys and 117 mmol (6.7 g of salt) among girls. Ninety-three percent of the boys and 89% of the girls had a consumption higher than the recommended age-specific standard dietary target. The estimated average daily potassium intakes were 39 mmol (1.53 g) and 36 mmol (1.40 g), respectively, over 96% of the boys and 98% of the girls having a potassium intake lower than the recommended adequate intake. The mean sodium/potassium ratio was similar among boys and girls (3.5 and 3.4, respectively) and over 3-fold greater than the desirable level. Sodium intake was directly related to age, body mass and BP in the whole population. Conclusions The Italian pediatric population is characterized by excessive sodium and deficient potassium intake. These data suggest that future campaigns should focus on children and adolescents as a major target in the framework of a population strategy of cardiovascular prevention.

ROLE OF DIFFERENT METABOLIC SYNDROME COMPONENTS ON THE RISK TO DEVELOP SLEEP APNOEA: PP.32.275

Objective: In various clinical studies, apnoea sleep disorders have been associated with different cardiovascular and metabolic abnormalities. The aim of this analysis was to assess the relation between a multivariable apnoea prediction index, metabolic syndrome (MS) and its single components in an unselected sample of adult male population. Design and Method: The relationship between MS (AHA 2005 criteria) and a high apnoea risk (HAR) evaluated by a multivariable apnoea prediction index higher than 0.5, was investigated in 612 (mean age ± SD = 59.7 ± 6.4 years) participants at the 2002–04 Olivetti Heart Study follow-up. Results: The prevalence of MS and of HAR were respectively 36.6% (n = 224) and 60.8% (n = 372). MS and HAR were strongly associated (χ2 = 26.3; p < 0.0001). The prevalence of HAR increased gradually with increasing number of MS components. (χ2 = 36.4; p < 0.0001), the higher the MS score, the higher the prevalence of HAR. Using a logistic regression analysis with apnoea risk as dependent variable and MS components and age as independent factors, hypertension (blood pressure > 130/85 mmHg or treatment) and central adiposity (waist circumference > 102 cm) remained the only determinants of HAR with odds ratio (95%CI) of respectively 2.57 (1.53 to 4.33) and 3.84 (2.47 to 5.98). Conclusion: In this sample of adult male population the prevalence of high apnoea risk was related to both presence and severity of metabolic syndrome. Among different components of MS, blood pressure and central adiposity were the factors more strongly associated to the risk to be affected by sleep apnoea disturbances.

PROXIMAL SODIUM REABSORPTION IS AN INDEPENDENT PREDICTOR OF HYPERTENSION: 2D.05

Objective: Given the association between salt-sensitivity of blood pressure (BP) and risk of future hypertension (HPT), we investigated the predictive role of alterations in segmental renal tubular sodium handling in the development of HPT during the 8 year follow-up of the Olivetti Heart Study participants. Methods: A selected sample (n = 314) of OHS population was examined at baseline and after 8 years. The participants were included if they were normotensive (SBP/DBP <140/90 mm Hg without anti-hypertensive treatment) and had normal renal function (creatinine clearance - CrCl> 60 ml/min) at baseline. Proximal and distal fractional tubular sodium reabsorption were calculated using the clearance of exogenous lithium. Results: The baseline sample characteristics were: age 49.3 ± 6.8 yrs, BMI 26.4 ± 2.8 kg/m2, SBP/DBP 119.8 ± 9.6/78.9 ± 6.4 mm Hg, CrCl 90.9 ± 18.2 mL/min (M ± SD). The HPT incidence in 8 years was 52%. The participants who developed HPT (group A) compared with those who did not (group B) had higher baseline SBP (122.4 ± 8.4 mm Hg vs 117.0 ± 10.0, p < 0.0001), DBP (80.6 ± 5.6 VS 77.1 ± 6.7 mm Hg, p < 0.0001), BMI (27.0 ± 2.9 vs 25.9 ± 2.6 kg/m2, p < 0.0001) and fractional proximal reabsorption of sodium (75.8 ± 6.3 vs 73.8 ± 7.3 %, p = 0.01). At logistic regression analysis using standardised variables, a 1SD-higher proximal sodium reabsorption at baseline predicted a 44% greater risk of HPT in 8 years (95% C.I. 13–84, p = 0.003), independently of baseline SBP (OR: 1.88, 95% C.I. 1.43–2.47, p < 0.001), BMI (OR: 1.51, 95% C.I. 1.16–1.95, p = 0.002), age and creatinine clearance used as an index of glomerular filtration rate. Conclusions: In this sample of healthy adult male population, proximal sodium reabsorption indexed to glomerular filtration rate was an independent predictor of future HPT.

SERUM URIC ACID PREDICTS THE DEVELOPMENT OF HYPERTENSION IN A SAMPLE OF MALE NORMOTENSIVE ADULTS: 1B.07

Objective: Cross-sectional and prospective studies showed that serum uric acid levels (SUA) and hypertension (HPT) are related. Our aim was to evaluate this relationship in a sample of healthy male adults, during an 8 year follow-up, in the Olivetti Heart Study. Methods: The population sample was made of 253 participants (mean age 49.5 years, range 26–71) examined both at the beginning (1994–95) and at the end of follow-up (2002–04). The participants were included in the analysis if at baseline they were non-diabetic, normotensive, not on pharmacological treatment for HPT, they had blood pressure (BP) less than 130/85 mmHg and normal renal function (creatinine clearance – CrCl > 60 ml/min). Results: Baseline SUA was directly related to BMI (r = 0.27; p < 0.0001), diastolic BP (r = 0.22; p < 0.0001) and HOMA index (r = 0.28; p < 0.0001) and inversely related to CrCl (r = −0.14; p = 0.02). The incidence of HPT (BP> = 140 and/or 90 mmHg or anti-hypertensive treatment) over 8 years was 45%. The participants who developed HPT had higher basal SUA compared with participants who did not (M ± SE: 5.76 ± 0.11 vs 5.36 ± 0.09 mg/dL; p = 0.006). Logistic regression analysis showed that standardised basal SUA significantly predicted the risk to develop HPT during 8 years (for 1SD higher SUA: OR = 1.40, 95% C.I. 1.06 to 1.86, p = 0.018), after adjustement for age, BMI, SBP, CrCl and HOMA index at baseline. Conclusions: This study revealed the predictive role of SUA on the development of hypertension in previously non diabetic normotensive subjects with normal renal function.