P. Redon

Cardiovascular fitness in youth: association with obesity and metabolic abnormalities

UNLABELLED Therapies currently implemented for obesity are focused on nutritional aspects and on physical activity. In order to make physical activity a positive therapy instead of triggering disabilities it is relevant to accurately assess cardiovascular fitness. OBJECTIVE To assess the cardiovascular fitness by measuring the peak oxygen consumption and to asses their relationship with classical cardiometabolic parameters. METHODS A modified Balke protocol was applied to one hundred and twenty-six Caucasians (60% males), ranging between 9 and 16 years old, who underwent an assessment of obesity. The non-obese group consisted of healthy age and sex matched subjects who were invited to participate from the general population. RESULTS Significant differences in consumption of oxygen peak between non-obese and obese individuals were observed. In contrast, no significant differences existed between the categories of obesity. Furthermore in obese subjects consumption of oxygen peak was inversely correlated with parameters of cardiometabolic risk, particularly insulin and HOMA index. In addition, two predictive equations of consumption of oxygen peak, with an R2 of 0.74 and 0.84, respectively, have been developed. CONCLUSION The consumption of oxygen peak is a relevant clinical parameter that should be included in the routine clinical assessment of obese subjects. Therefore, it is crucial to make exercise tests more affordable which can be achieved by employing predictive equations.

URIC ACID IS ASSOCIATED WITH CARDIOMETABOLIC RISK FACTORS IN OVERWEIGHT AND OBESE CHILDREN AND ADOLESCENTS

Objective: This study examined the association of serum uric acid (UA) with levels of cardiometabolic risk factors in overweight and moderate obese children and adolescents. Design and method: Three hundred and thirty three Caucasians of both sexes (149 females), of European origin, from 5 to 18 years of age (mean age 11.4 2.6) were included. Overweight and obesity were defined based on the extended international body mass index cut-offs. The subjects were divided into 3 groups according to serum UA: <5 mg/dl n = 118 subjects (35%); UA 5-6 mg/dl n = 130 subjects (39%) or UA>6 mg/dl n = 85 subjects (26%). Fasting blood was obtained and uric acid, glucose, insulin, and lipid profile, were measured. Likewise office BP and 24-hour ABPM were assessed. Hyperinsulinemia was defined from norms for pubertal stage. Abnormal fasting lipids were defined from normative data (Daniels et al, 2008). Subjects were qualified as normotensive, high-normal or hypertensive according to the ESH criteria (Lurbe et al, 2016). Results: There were significant differences among groups regarding, BMI, waist, fasting insulin, office SBP and night-time SBP increasing progressively across the serum UA groups. Controlling by age and sex, uric acid was significantly correlated with BMI (r = 0.27, p = 0.000), waist (r = 0.33; p = 0.000), birth weight (r = −0.11; p = 0.05), office SBP (r = 0.21; p = 0.000), daytime SBP, (r = 0.16; p = 0.03), nighttime SBP (r = 0.24; p = 0.000), insulin (r = 0.25; p = 0.000), and Log Tryglicerides (r = −0.137; p = 0.019). In a multiple regression analysis sex, waist, birth weight, SBP (office, daytime and nighttime), were independent determinants of uric acid when age, BMI, HDL-C and insulin were included (R2 = 0.29). The prevalence of hyperinsulinemia, low HDL-C, high-normal BP, and hypertension in each UA group are shown in the Figure. Figure. No caption available. Conclusions: In overweight and moderate obese children and adolescents there is a trend toward greater prevalence of cardiometabolic risk factors as the uric acid values rose. The role of hyperuricemia and its association with cardiometabolic risk factors should receive more attention, beginning in early childhood.

DIFFERENCES IN THE PREVALENCE OF BLOOD PRESSURE CONDITIONS USING ESH VS AAP GUIDELINES IN CHILDREN AND ADOLESCENTS

Objective: The objective is to assess differences in the prevalence of blood pressure (BP) conditions according to the European Society of Hypertension (ESH) guidelines (Lurbe, J Hypertens 2016) and the American Academy of Pediatrics (AAP) (Flynn, Pediatrics 2017) in children and adolescents. Design and method: Four thousand two hundred and ninety-six Caucasians of both sexes (1941 females), of European origin, from 5 to 18 years of age (mean age 11.5 3.3) in the absence of antihypertensive treatment were included. Overweight and obesity (n = 2243) were defined based on the extended international body mass index cut-offs. Office BP was measured in the non-dominant arm with cuff and bladder size adjusted to upper-arm girth. The three measurements of each office visit were averaged for analysis. Twenty-four-hour ambulatory BP monitoring was performed by using Spacelabs monitor 90207. Subjects were qualified as true normotensive (N), white-coat (WC), masked (M) or sustained hypertensive (HTN) according to the ESH and AAP criteria for office BP, and reference values for 24-hour ambulatory BP (Wühl, J Hypertens 2002). Results: The prevalence of N, WC, M and HTN were significantly different when the ESH or AAP were applied. Overall, the largest differences were observed in the prevalence of WC, which was double when the AAP criteria were used. The differences were larger for boys, older than 13 years of age. The presence of obesity did not reduce the higher prevalence of WC by the AAP criteria. In contrast, M was slightly higher when the ESH criteria were applied. The impact on the prevalence of WC and M is shown in the figure. Figure. No caption available. Conclusions: When applying the AAP criteria, compared with that of the ESH, the main difference is the higher prevalence of WC, especially in boys aged 13 years or older. The consequence is an increment of the HTN work-up in children and adolescents.

[PP.11.28] UNRAVELING THE URIC ACID IN THE CLUSTER OF CARDIOMETABOLIC RISK FACTORS EARLY IN LIFE: A PROSPECTIVE STUDY

Objective: The present prospective research, starting at birth, was undertaken to analyze factors related to the uric acid in children at 5 years old. Design and method: One hundred and fifty four Caucasians of both sexes (77 females), of European origin, born at term were included. After the initial evaluation on the second day of life, infants were followed up and growth pattern prospectively recorded. At five years, office BP measurements were performed and fasting blood sample was obtained to measure glucose, insulin, lipid profile, and uric acid. All subjects were normotensives, no diabetes neither dyslipidemia were present. Results: In this prospective study, uric acid at five years depends positively on the increment of weight from birth (p < 0.001) and inversely of the birth weight (p < 0.05). Furthermore, uric acid was significantly correlated with current weight (r = 0.25; p = 0.003), current height (r = 0.17; p = 0.04), office SBP (r = 0.23; p = 0005), insulin (r = 0.36; p = 0.001), and HDL (r = −0.30; p = 0.001). In a multiple regression analysis insulin, and HDL cholesterol were independent determinants of uric acid when, sex, current weight, birth weight, SBP, and Log triglycerides were also included (r2 = 0.23). The weighted impact of uric acid on metabolic parameters and office SBP, adjusted by sex and body weight, are shown in the Table. https://services.aimgroup.it/ASPClient/files/3465/Abstract/669_20170102111446.jpg Figure. No caption available. Conclusions: Uric acid is associated with metabolic parameters independent of office BP. Metabolic status at 5-year-old in children born at term may be influenced by perinatal events and postnatal rapid weight gain with clinical implications that require active intervention to prevent or reverse upward crossing of weight percentiles.

Sympathetic neural activity, metabolic parameters and cardiorespiratory fitness in obese youths

Objective: The main objective of this cross-sectional study is to assess the cardiac autonomic neural activity in the presence of abnormally increased body weight in youths and its relationship to metabolic risk factors and cardiorespiratory fitness (CRF). Methods: Sixty-four overweight and obese patients, aged 9–17 years, of both sexes, stratified according to the international BMI cut-off, were enrolled. Continuous ECG was recorded during 15 min in resting conditions, and the heart rate variability (HRV) was measured in the time domain, frequency domain and for nonlinear dynamics. In addition, cardiometabolic risk factors and CRF in effort conditions were assessed. Results: Among the overweight and obese youths, no significant differences were observed regarding metabolic parameters and heart rate, although CRF was the lowest in the severely obese youths. Likewise, no significant differences were observed in HRV, independent of how it was assessed. A positive and significant relationship, independent of the degree of obesity, pubertal stage and breathing rate under resting conditions, has been observed among sympathovagal balance, insulin and the homeostatic model assessment index. Furthermore, CRF assessed by volume oxygen peak was associated with insulin levels (r = −0.273; P < 0.05), the SD of the NN interval series (r = 0.268, P < 0.05) and the long-term variation using the Poincaré plot (PS1: r = 0.275, P < 0.05; PS2: r = 0.273, P < 0.05). Conclusion: The key findings of the present study were the presence of a link among fasting insulin, HRV and CRF independent of the degree of obesity, indicating the heterogeneity of obese children and adolescents.

[OP.6A.06] VASCULAR PHENOTYPES BY ASSESSING PERIPHERAL AND CENTRAL BLOOD PRESSURE IN OBESE YOUTH.

Objective: To identify vascular phenotypes across BP conditions in overweight and obese youths, by assessing office (oBP) and central BP (cBP), and pulse pressure amplification. Whether or not 24-hour ambulatory BP monitoring and pulse wave velocity (PWV) add insight to the issue has also been examined. Design and method: White youths of both sexes with overweight or obesity and of European origin, ranging from 8 to 18 years of age, were included. Office BP, cBP, PWV, and 24-hour ABPM were measured. Office BP conditions and “white-coat” HTN were defined as recommend by ESH Guidelines in Children and Adolescents. Subjects were divided into subgroups of “normal” or “high” according to cBP and PP ratio. Results: A total of 593 subjects (mean age, 12.2 ± 2.3 years; 275 females) were included in the study. The largest differences between oSBP and cSBP correspond to the isolated systolic HTN (ISH) group, in which only 25% of subjects have high cBP, in contrast to 50% of the systo-diastolic HTN (SDH) group. In the hypertensive youth two patterns emerged based on cBP and PP ratio. The highest cBP was among the SDH and the highest PP ratio in the ISH group (see Figure). While, 90% of the SDH were confirmed with 24-hour ABPM, 75% of the ISH were white-coat. PWV showed a progressive increment across the groups from NT to SDH. Significant differences were observed only when compared to the NT, but not among all other groups. Figure. No caption available. Conclusions: In overweight and obese hypertensives, ISH is prevalent posing a challenge for the clinician of whether these may therefore be diagnosed and managed as hypertensives. Until prospective studies can give more information, 24-hour ABPM can offer information for making clinical decisions.

2B.04: FACTORS RELATED TO THE LINK BETWEEN URIC ACID AND SYSTOLIC BLOOD PRESSURE IN YOUTHS.

Objective: The present research was undertaken to analyze factors related to the link between uric acid (UA) and office blood pressure (BP) in normotensive, high-normal and untreated essential hypertensive youths. Design and method: Six hundred and forty three Caucasians of both sexes (321 females), of European origin, predominantly obese, from 6 to 18 years of age (mean age 11.7 2.4) were included. The subjects were divided into 3 groups: normotensives 559 (87%; 92 non-obese), high-normal BP 58 (9%; 19 non-obese) or hypertensives 26 (4%; 5 non-obese) according to the ESH office BP criteria (Lurbe et al, J Hypertens 2009). Fasting blood was obtained and glucose, insulin, lipid profile, and UA were assessed. Results: In relation to the general characteristics, there were no differences among groups regarding age, BMI, BMI-zscore, HDL and insulin. Uric acid increases across the BP range from normotensive to hypertensive groups. Controlling by age and sex, UA was significantly correlated with BMI (r = 0.180, p = 0.000), BMI Z-score (r = 0.175; p = 0.000), SBP (r = 0.20; p = 0.000), insulin (r = 0.23; p = 0.000), and HDL (r = -0.149; p = 0.000). In a multiple regression analysis office SBP, insulin, and HDL cholesterol were independent determinants of UA when age, sex, and BMI were included (r2 = 0.25). Office systolic BP was the main determinant of UA in a stepwise analysis. Even though UA was corrected by body size, UA/BMI ratio, systolic BP was the main determinant in boys (See figure). Figure. No caption available. Conclusions: Uric acid is associated with BP, independently of metabolic factors in boys. The clinical implications require further investigation.