The association of sleep duration and cardiometabolic risk factors in a national sample of children and adolescents: The CASPIAN III Study

ObjectivesAlthough sleep duration is one of the most important health-related factors, its association with risk factors for chronic diseases has not been completely clarified, especially among children and adolescents. The aim of this study was to evaluate the association between sleep duration and CVD risk factors among a nationally representative sample of Iranian children and adolescents.MethodsThis cross-sectional national study was performed on a representative sample of 5528 Iranian students, ages 10 to 18 y living in central cities of 27 provinces of Iran. Physical examinations and laboratory tests were performed using standard protocols. To determine the association between sleep duration and cardiometabolic risk factors, multivariable logistic regression was used and odds ratios (OR; with 95% confidence intervals) are reported.ResultsThe mean ± SD age was not significantly different among boys (14.69 ± 2.45 y) and girls (14.7 ± 2.38 y). In a crude model, boys who slept > 8 h and 5 to 8 h had lower OR for abdominal obesity compared with those who had slept <5 h in a crude model (ORs, 0.70, 0.80, 1.0, respectively; P = 0.008). A similar result was observed in an age- adjusted model for the prevalence of abdominal obesity (ORs, 0.69, 0.76, 1.0, respectively; P = 0.011). Girls who had slept > 8 h per day had lower OR for high serum low-density lipoprotein levels compared with those who slept < 5 h per day (P = 0.002). These differences remained significant even in the fully adjusted model for all the confounding variables (P = 0.008). Moreover, among boys ages 10 to 14 y, longer sleep duration increased the risk for high total cholesterol in all models.ConclusionShorter sleep duration increased the risk for some cardiometabolic risk factors among adolescents. The clinical significance of our findings should be determined in longitudinal studies.     

Using factor analysis to identify dietary patterns in Iranian adults: Isfahan Healthy Heart Program

Objective  

To identify dietary patterns of a representative sample of Iranian adults using factor analysis.     

Absence of Association between -1131T>C Polymorphism in the Apolipoprotein APOA5 Gene and Pediatric Metabolic Syndrome

Objective: In the present study, we evaluated the association of rs662799 variant of the APOA5 gene with Metabolic syndrome (MetS) in a sample of children and adolescents from Isfahan. Methods: This case control study comprised 50 cases of MetS and 50 controls. Mismatched polymerase chain reaction–restriction fragment length polymorphism (mPCR-RFLP) was used to genotype -1131T>C polymorphism. Findings : No significant association was documented for APOA5 genotypes with the measured laboratory parameters for CC, CT, and TT genotypes in the two groups studied. By logistic regression using a dominant model, the odds ratio (95% confidence interval0 for the MetS was 0.38 (0.139–1.0350 and 0.29 (0.08–1.071 for the unadjusted and adjusted models, respectively. Conclusion: This study suggests that among studied children and adolescents, -1131T>C polymorphism in the APOA5 gene may not be a major contributor to the MetS risk.Key Words: Apolipoprotein A5 Gene; Metabolic Syndrome; Children; Adolescents; Triglyceride; Cholesterol     

Genetic association with low concentrations of high density lipoprotein-cholesterol in a pediatric population of the Middle East and North Africa: The CASPIAN-III study

Objective

Depressed high-density lipoprotein cholesterol (HDL-C) is prevalent the Middle East and North Africa. Some studies have documented associations between HDL-C and several single nucleotide polymorphisms (SNPs) in candidate gene polymorphisms.

Methods

We investigated the associations between SNP genotypes and HDL-C levels in Iranian students, aged 10–18 years. Genotyping was performed in 750 randomly selected participants among those with low HDL-C levels (below 5th percentile), intermediate HDL-C levels (5–95th) and high HDL-C levels (above the 95th percentile). Minor allele frequencies (MAFs) of the SNPs of interest were compared between the three HDL-C groups.

Results

The vast majority of pairwise comparisons of MAFs between HDL-C groups were significant. Pairwise comparisons between low and high HDL-C groups showed significant between-group differences in MAFs for all SNPs, except for APOC3 rs5128. Pairwise comparisons between low and intermediate HDL-C groups showed significant between-group differences in MAFs for all SNPs, except for APOC3 rs5128 and APOA1 rs2893157. Pairwise comparisons between intermediate and high HDL-C groups showed significant between-group differences in MAFs for all SNPs, except for ABCA1 APOC3 rs5128 and APOA1 rs2893157. After adjustment for confounding factors, including age, sex, body mass index, low physical activity, consumption of saturated fats, and socioeconomic status, ABCA1 r1587K and CETP A373P significantly increased the risk of depressed HDL-C, and CETP Taq1 had a protective role.

Conclusion

This study replicated several associations between HDL-C levels and candidate gene SNPs from genome-wide associations with HDL-C in Iranians from the pediatric age group.     

Regional Disparities in Sedentary Behaviors and Meal Frequency in Iranian Adolescents: The CASPIAN-III Study

Background:

The prevalence of obesity is increasing among Iranian youngsters like other developing countries.

Objectives:

This study was conducted to assess regional disparities in sedentary behaviors and meal frequency in Iranian adolescents.

Patients and Methods:

In this national survey, 5682 students aged 10 - 18 years from urban and rural districts of 27 provinces of Iran were selected via stratified multi-stage sampling method. The country was classified into four sub-national regions, based on criteria of the combination of geography and socioeconomic status (SES). Mean of meal frequency and physical activity levels as well as prevalence of omitting meals and sedentary behavior were compared across regions with different SES after stratifying with sex and age group.

Results:

Meal frequency in lower socio-economic regions was significantly higher than two other regions in 10 - 13 and 10 - 18 years old groups (P trend < 0.001). However, the mean of working hours with computer was linearly increased with increasing the SES in studied regions (P trend < 0.001), whereas the corresponding figure was not significant for the mean of watching TV (P trend > 0.05). Frequency of adolescents omitting their meals was higher in higher SES regions especially in West Iran (P < 0.001) in 10 - 13 years old age group. Having personal computer and working with it more than two hours per day mainly was observed in central Iran which ranked as the highest SES group.

Conclusions:

Efforts to ensure Iranian youth meet healthy food habits and screen time guidelines include limiting access to screen technologies and encouraging parents to monitor their own screen time is required.     

Prevalence of General and Abdominal Obesity in a Nationally Representative Sample of Iranian Children and Adolescents: The CASPIAN-IV Study

Background:

Pediatric obesity is one of the predisposing risk factors for many non-communicable diseases.

Objectives:

The purpose of this study was to estimate the national prevalence of general and abdominal obesity among Iranian children and adolescents.

Patients and Methods:

This cross-sectional nation-wide study was performed in 30 provinces in Iran among 14880 school students aged 6 – 18 years, selected by multistage random cluster sampling. The World Health Organization growth curve was used to categorize Body Mass Index (BMI). Obesity was defined as BMI equal to or higher than the age- and gender-specific 95^th percentile; abdominal obesity was considered as waist-to-height ratio of more than 0.5.

Results:

Data of 13486 out of 14880 invited students were complete (response rate of 90.6%). They consisted of 6543 girls and 75.6% urban residents, and had a mean age of 12.45 (95% CI: 12.40 - 12.51) years. The prevalence rate of general and abdominal obesity was 11.89% (13.58% of boys vs. 10.15% of girls) and 19.12% (20.41% of boys vs. 17.79% of girls), respectively. The highest frequency of obesity was found in the middle school students (13.87% general and 20.84% abdominal obesity). The highest prevalence of general obesity was found in Boushehr (19%) followed by Guilan and Mazandaran (18.3%, 18.3%), while the lowest prevalence was observed in Hormozgan (2.6%). The highest frequency of abdominal obesity was found in Mazandaran (30.2%), Ardabil (29.2%) and Tehran (27.9%). Provinces such as Sistan-Baloochestan (8.4%), Hormozagan (7.4%), and Kerman (11.4%) had the lowest prevalence of abdominal obesity. The Southern and South Eastern provinces had the lowest prevalence of general obesity (2.6% and 5.6%) and abdominal obesity (7.4% and 8.8%). Moreover, the highest prevalence of obesity was found in North and North West Iran by maximum frequency of 18.3% general obesity and 30.2% of abdominal obesity.

Conclusions:

The results showed a high prevalence of general and abdominal obesity among boys living in the Northern provinces of Iran. The present study provides insights that policy makers should consider action-oriented interventions for prevention and control of childhood obesity at national and sub-national level.     

Early graft failure of GalTKO pig organs in baboons is reduced by expression of a human complement pathway‐regulatory protein

We describe the incidence of early graft failure (EGF, defined as loss of function from any cause within 3 days after transplant) in a large cohort of GalTKO pig organs transplanted into baboons in three centers, and the effect of additional expression of a human complement pathway‐regulatory protein, CD46 or CD55 (GalTKO.hCPRP). Baboon recipients of life‐supporting GalTKO kidney (n = 7) or heterotopic heart (n = 14) grafts received either no immunosuppression (n = 4), or one of several partial or full immunosuppressive regimens (n = 17). Fourteen additional baboons received a GalTKO.hCPRP kidney (n = 5) or heart (n = 9) and similar treatment regimens. Immunologic, pathologic, and coagulation parameters were measured at frequent intervals. EGF of GalTKO organs occurred in 9/21 baboons (43%). hCPRP expression reduced the GalTKO EGF incidence to 7% (1/14; P < 0.01 vs. GalTKO alone). At 30 mins, complement deposits were more intense in organs in which EGF developed (P < 0.005). The intensity of peri‐transplant platelet activation (as β‐thromboglobulin release) correlated with EGF, as did the cumulative coagulation score (P < 0.01). We conclude that (i) the transgenic expression of a hCPRP on the vascular endothelium of a GalTKO pig reduces the incidence of EGF and reduces complement deposition, (ii) complement deposition and platelet activation correlate with early GalTKO organ failure, and (iii) the expression of a hCPRP reduces EGF but does not prevent systemic coagulation activation. Additional strategies will be required to control coagulation activation.     

Is the association of continuous metabolic syndrome risk score with body mass index independent of physical activity? The CASPIAN-III study

BACKGROUND/OBJECTIVESAlthough the association of body mass index (BMI) with metabolic syndrome (MetS) is well documented, there is little knowledge on the independent and joint associations of BMI and physical activity with MetS risk based on a continuous scoring system. This study was designed to explore the effect of physical activity on interactions between excess body weight and continuous metabolic syndrome (cMetS) in a nationwide survey of Iranian children and adolescents.SUBJECTS/METHODSData on 5,625 school students between 10 and 18 years of age were analyzed. BMI percentiles, screen time activity (STA), leisure time physical activity (LTPA) levels, and components of cMetS risk score were extracted. Standardized residuals (z-scores) were calculated for MetS components. Linear regression models were used to study the interactions between different combinations of cMetS, LTPA, and BMI percentiles.RESULTSOverall, 984 (17.5%) subjects were underweight, whereas 501 (8.9%) and 451 (8%) participants were overweight and obese, respectively. All standardized values for cMetS components, except fasting blood glucose level, were directly correlated with BMI percentiles in all models (P-trend < 0.001); these associations were independent of STA and LTPA levels. Linear associations were also observed among LTPA and standardized residuals for blood pressure, high-density lipoprotein, and waist circumference (P-trend < 0.01).CONCLUSIONSOur findings suggest that BMI percentiles are associated with cMetS risk score independent of LTPA and STA levels.     

Performance of modified blood pressure‐to‐height ratio for diagnosis of hypertension in children: The CASPIAN‐V study

This study aimed to evaluate the accuracy and performance of modified blood pressure‐to‐height ratio (MBPHR) for identifying high blood pressure (HBP) in a large population of children. This multicentric cross‐sectional study was conducted on a nationally representative sample of 7349 Iranian students aged 7‐12 years living in 30 provinces in Iran. High systolic blood pressure and diastolic blood pressure were defined according to the 2017 American Academy of Pediatrics (AAP) guidelines. The BP‐to height ratio (BPHR) was calculated as BP (mmHg)/height (cm), MBPHR3 as BP (mmHg)/(height (cm) + 3 (13‐age)), and MBPHR7 as BP (mmHg)/(height (cm) + 7 (13‐age). The receiver‐operating characteristic curve analysis was used to evaluate the performance of these three ratios for identification of HBP in children compared to the 2017 AAP guidelines as the gold standard. Mean age of participants was 12.29 ± 3.15 years and 3736 (50.8%) were girls. The prevalence of HBP was 11.9% (11.5% in boys, 12.3% in girls). The area under the curve (AUC) was higher for MSBPHR3/MDBPHR3 (0.97/0.98) than MSBPHR7/MDBPHR7 (0.96/0.97) and SBPHR/DBPHR (0.96/0.95) for identifying high Systolic and diastolic BP. The optimal cut‐off points for MSBPHR3/MDBPH, MSBPHR7/MDBPHR7, and SBPHR/DBPHR were 0.76/0.50, 0.69/0.46, and 0.81/0.52 respectively. Negative predictive value was nearly perfect for three ratios (≥98%). Positive predictive value was higher for MBPHR3 (52.7%) than MBPHR7 (51.0%) and BPHR (39.8%). Overall, MBPHR3 had better performance than MBPHR7 and BPHR for identification of HBP in Iranian children and it may improve early hypertension recognition and control in primary screening.