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Sumario Vol. 43 - Nº 1 Enero - Marzo 2014

TG/HDL Index in adolescents of Salta, Argentina

Susana Judith Gotthelf

Departamento de Investigación Epidemiológica.
Centro Nacional de Investigaciones Nutricionales.
Administración Nacional de Laboratorios e Institutos de Salud. ANLIS.
(4400) Salta, Argentina.
E mail

Recibido 02-DIC-13 – ACEPTADO 06-ENERO-2014.

The author declare not having a conflict of interest.

Rev Fed Arg Cardiol. 2014; 43(1): 18-24


Print version Imprimir sólo la columna central

 

 

SUMMARY
Introduction: The TG / HDL index has been described as a predictor of cardiometabolic risk closely related to insulin resistance and an atherogenic lipid profile.
Objective: To assess the prevalence of TG / HDL index among adolescent students of the Province of Salta and its relationship to family,nutritional and biochemical factors.
Material and Methods: Cross-sectional study. Population:659 adolescents between 16 and 20 years old, attending the  last grade of public and private high schools of Salta, Cafayate and Joaquín González (2008-09). Variables: high TG/HDL ≥3. MS IDF criteria: ≥80cm waist circumference women, men ≥90 cm, TG ≥ 150 mg / dl, HDL ≤50mg/dl women, men ≤40mg/dL, systolic / diastolic blood pressure ≥130/85 mmHg, fasting glucose ≥100mg/dl. LDL and cholesterol. BMI z score (WHO). Sociodemographic: sex, residence, family income. Parental history of obesity, hypertension, diabetes, hypercholesterolemia, and cardiovascular disease.
Statistical analysis
: Chi square, Fisher (proportions). Kolgomorov (normality), Mann- Whitney U, Kruskal Wallis (median). Logistic regression (SPSS17) p<0.05.
Results: The prevalence of high TG/HDL was 11.8%, 8.6% in women and 16.4% in men (p = 0.003), 9.6% at the Capital city and 15% in the rest of the province (p = 0.04) and 9.6% in normally nourished and 22.2% in overweight / obese individuals (p = 0.000). Median BG and CHOL were significantly higher in those with high TG/HDL.The OR for high TG/HDL was associated with male sex (OR 2.40 CI:1.05 -5.46), overweight / obesity (OR 3.05 CI: 1.56 -5.97), to beingfrom the rest of the province (OR 3.53 CI:1.62-7.66) and parental history of hypertension (OR 2.22 CI:1.14-4.39) and diabetes (OR 2.40 CI;0.99-5.80).
Conclusions: The TG/HDL index is easy to apply and could be useful for measuring the metabolic risk associated with obesity in adolescents.
Key words: TG / HDL index. Adolescence. Metabolic risk.

 

INTRODUCTION
Cardiovascular diseases are the main cause of death in the world. Argentina has experienced an increase in the prevalence of overweight and factors associated to Cardiovascular Diseases (CVD) in different ages and regions [1,2]. The province of Salta (Argentina) and within it the group of adolescents, have not been excluded from this reality, and different papers published from the Proyecto de Factores de Riesgo Cardiovascular, developed by the Centro Nacional de Investigaciones Nutricionales, have shown risk profiles associated to overweight, dyslipidemia and hypertension, with different characteristics according to the residence areas, gender and socio-economic family situation [3,4].

The risk factors associated to CVD appear early in childhood and adolescence, with repercussions on quality of life. Overweight, an increase in blood lipids and blood pressure in adolescence have been associated to a greater risk of cardiovascular diseases and to remaining influential from childhood into adulthood [6]. Young people with overweight present an increased risk of hypertension and dyslipidemia [6], and the altered patterns of lipids are considered predictors of the values to be reached in adulthood.

There are different criteria to stratify cardiovascular risk in individuals, according to the alterations presented: family history, body measurements, lab tests, etc.; and facilitating the application of these is a goal of clinical practice. Among them, the triglyceride/HDL cholesterol ratio has been described as a predictor of cardiometabolic risk closely related to insulin resistance and to a clearly atherogenic lipid profile [7].

 

Objective
To evaluate the prevalence of the TG/HDL index in teenagers in school in the province of Salta and its relation to nutrition, biochemical and family factors.

 

MATERIAL AND METHODS
Cross-sectional, descriptive study.

Population: Male and female students with ages ranging from 16 to 20 years, attending the last course of the Secondary School in public and private schools of the province of Salta (Capital city, Cafayate and Joaquín V. González), evaluated in the school term (2008-2009).

The data were obtained from the data base of the study Factores de Riesgo Cardiovascular en Adolescents de la Provincia de Salta (Cardiovascular Risk Factors in Adolescents from the Province of Salta), conducted between years 2008-2009. The study used a single, random, probabilistic sample of public and private schools in the city of Salta; while in the interior all the schools, all public, were assessed.

Exclusion criteria: carriers of known chronic diseases, eating disorders (anorexia, bulimia), pregnant women, students with <10 hour fasting, not authorized by parents or tutors, without the consent to participate.

Variables

  • High TG/HDL index ≥3.
  • MS (metabolic syndrome): IDF (International Diabetes Federation) criteria, waist circumference (WC) in women ≥80 cm and in men ≥90 cm plus two of the following elements present: TG ≥150 mg/dl; HDL: women ≤50 mg/dl and men ≤40 mg/dl; systolic/diastolic pressure ≥130/85 mmHg; basal glycemia ≥100 mg/dl [8].
  • CHOL ≥200; LDL ≥130.
  • Sociodemographic: gender, place of residence (capital city/interior of the province).

Nutrition state: 16-18 years of age. Z score tables of BMI according to gender and age (WHO) [9]: malnutrition ≤2 z score; normal >2 <+1; overweight ≥+1, obesity ≥+2.
19 years of age: malnutrition <18.5; normal ≥18.5 <25; overweight ≥25 <30; obesity ≥30 (WHO)[10].
Anthropometric measurements were made following the Sociedad Argentina de Pediatría guidelines [11]. Because of the low prevalence of malnutrition, for the analysis there was a regrouping with the category of normalcy.

Biochemical: HDL, Triglycerides (TG), basal glycemia (BG), LDL and CHOL in a 10 h fasting state by venous puncture, dry chemistry method with processor with ability for automatic dilution, Model Vitros 250 Johnson. Internal and external calibrations of the PEC (Quality Control Program of the Fundación Bioquímica Argentina).

Family variables: (autoreferential survey by the parents).

  • Family income: low, medium, high. Data from the INDEC, April 2008, for this region. For the final regression model, regrouped into two categories based on similarities: low (low+medium) and high.
  • BMI (Body Mass Index): weight and height.
  • High cholesterol, diabetes, hypertension, heart disease.

Statistical analysis: The results are presented in tables and graphs of distribution of frequencies and association, Chi-squared test, Fisher’s exact test, Kolgomorov (normality), Mann-WhitneyU, Kruskal Wallis (comparison of medians), multivariate logistic regression analysis, estimations of risks estimated by odds ratio (OR) with 95% CI. Statistical analysis: SPSS 17 (Windows version).

Ethical aspects
The original study from which the data were obtained, had the support by the Committee on Bioethics of the Sociedad Argentina de Pediatría, Salta Branch. At the time, all the parents or tutors of the teenagers that participated signed a written authorization, plus a signed consent by the students proper. The study was not financed by private companies, since it was organized by the Centro Nacional de Investigaciones Nutricionales de Salta, within the framework of the budget of activities by the Administración Nacional de Laboratorios e Institutos de Salud (ANLIS).

 

RESULTS
There were 659 students assessed, with ages ranging from 16 to 20 years.

Table 1 shows the prevalence of increased TG/HDL (11.8%-8.6% in women and 16.4% in men, p=0.002).

VARIABLES

FEMALES

MALES

TOTAL

 

 

n

%

n

%

n

%

  p

Capital
Interior

222
163
385

57.7
42.3
100.0

164
110
274

59.9
40.1
100.0

386
273
659

58.6
41.4
100.0

0.31

Student nutrition state
N/M
Ow/Ob


320
65
385


83.1
16.9
100.0


222
52
274


81.0
19.0
100.0


542
117
659


82.2
17.8
100.0


0.28

MS (-)
MS(+)

373
12
385

96.9
3.1
100.0

259
15
100.0

94.5
5.5
100.0

632
27
659

95.9
4.1
100.0

0.09

TG/HDL index
Normal
Increased


352
33
385


91.4
8.6
100.0


229
45
274


83.6
16.4
100.0


581
78
659


88.2
11.8
100.0


0.002

CHOL  Normal
Increased

336
49
385

87.3
12.7
100.0

253
21
274

92.3
7.7
100.0

589
70
659

89.4
10.6
100.0

0.024

LDL Normal
Increased

358
27
385

93.0
7.0
100.0

262
12
274

95.6
4.4
100.0

620
39
659

94.1
5.9
100.0

0.106

Family income
Low
High


249
134
383


65.0
35.0
100.0


175
97
272


64.3
35.7
100.0


424
231
655


66.7
35.3
100.0


0.46

Parental hist of HTN
NO
YES


307
75
382


80.4
19.6
100.0


90
40
130


69.2
30.8
100.0


397
115
512


77.5
22.5
100.0


0.007

Parental hist of DM
NO
YES


360
22
382


94.2
5.8
100.0


112
17
129


86.8
13.2
100.0


472
39
511


92.4
7.6
100.0


0.007

Parental history of high CHOL
NO
YES



326
22
382



85.3
14.7
100.0



96
33
129



74.4
25.6
100.0



422
89
511



82.6
17.4
100.0



0.004

Parental history of CVD
NO
YES


344
38
382


90.1
9.9
100.0


107
22
129


82.9
17.1
100.0


451
60
511


88.3
11.7
100.0


0.025

Father nutrition state
N/M
Ow/Ob


67
229
296


22.6
77.4
100.0


24
73
97


24.7
75.3
100.0


91
302
393


23.2
76.8
100.0


0. 38

Mother nutrition state
N/M
Ow/Ob


167
184
351


47.6
52.4
100.0


36
76
112


32.1
67.9
100.0


203
260
463


43.8
56.2
100.0


0.003

N/M: normal/malnutrition. Ow/Ob: overweight/obesity. HTN: hypertension. Chi squared p<0.05.

 
Table 1. Basal characteristics according to the gender of teenagers
in school from the province of Salta. 2013. CNIN.

Figure 1 highlights the prevalence of MS of 5.5% in males and 3.1% in females.

Figure 1

Table 2 shows the increased prevalence of TG/HDL, 9.6% in the Capital city and 15.0% in the interior of the province (p=0.04); 9.6% in normally nourished  individuals and 22.2% in those with overweight/obesity (p=0.000). Bivariate analysis observed significant associations between the presence of MS (OR 15.91; CI: 6.98-36.29, p=0.000) and some of its components: systolic pressure OR 2.30 (CI: 1.41-3.75, p=0.001); waist circumference: OR 2.33 (CI 1.28-4.24, p=0.006) with high TG/HDL index.

Variables

 

NormalTG/HDL
n%

 TG/HDL ≥3 n       %

OR     CI

p

Females
Males

352
229

91.4
83.6

33
45

8.6
16.4


2.09   1.30-3.38


0.003

Capital
Interior

349
232

90.4
85.0

37
41

9.6
15.0


1.67   1.04-2.68


0.04

Student nutrition state
N/M
Ow/Ob



490
91



90.4
77.8



52
26



9.6
22.2



2.69   1.60-4.53



0.000

MS (-)
MS (+)

571
10

90.3
37.0

61
17

9.7
63.0

15.91  6.98-36.29

0.000

SBP  Normal
Increased

446
135

90.7
80.8

46
32

9.3
19.2

2.3   1.41-3.75

0.001

DBP Normal
Increased

551
30

88.3
85.7

73
5

11.7
14.3

1.26   0.47-3.34

0.59

WC  Normal
Increased

519
62

89.5
78.5

61
17

10.5
21.5

2.33     1.28-4.24

0.008

BG   Normal
Increased

569
12

88.4
80.0

75
3

11.6
20.0

1.89    0.52-6.87

0.40

Family income

  • Low
  • High

 


380
197

 


89.6
85.3

 


44
34

 


10.4
14.7

 


1.49     0.92-2.41

 


0.10

Father nutrition state

  • N/M
  • Ow/Ob

 



86
274

 



94.5
90.7

 



5
28

 



5.5
9.3

 



1.76     0.66-4.69

 



0.38

Mother nutrition state

  • N/M
  • Ow/Ob

 



180
237

 



88.7
91.2

 



23
23

 



11.3
8.8

 



0.76     0.41-1.40

 



0.43

Parental HTN history

  • NO
  • YES

 


366
96

 


92.2
83.5

 


31
19

 


7.8
16.5

 


2.34     1.26-4.32

 


0.01

Parental DM history

  • NO
  • YES

 


431
30

 


91.3
76.9

 


41
9

 


8.7
23.1

 


3.15     1.40-7.09

 


0.009

Parental history high CHOL

  • NO
  • YES

 



385
76

 



91.2
85.4

 



37
13

 



8.8
14.6

 



1.78     0.90-3.51

 



0.11

Parental CVD history
NO
YES

 

413
48

 

91.6
80.0

 

38
12

 

8.4
20.0

 

2.72     1.33-5.55

 

0.009

N/M: normal / malnutrition. Ow/Ob: overweight / obesity. S/DBP: systolic / diastolic blood pressure. WC: waist circumference. BG: basal glycemia. HTN: hypertension. CVD: cardiovascular disease. Chi squared p<0.05.

 
Table 2. TG/HDL ratio with variables of study in teenagers in school
from the province of Salta. 2013. CNIN.

Moreover, a significant association was observed with family history of hypertension, diabetes and cardiovascular disease.

Table 3 shows the medians of BMI, WC, systemic BP, BG and CHOL that were significantly higher in students with high TG/HDL.

Variables

NormalTG/HDL

High TG/HDL (≥3)

P value

BMI

21.22

22.65

0.000

WC

72.50 cm

76.80 cm

0.000

SBP

120 mmHg

127 mmHg

0.000

DBP

69 mmHg

72.50 mmHg

0.065

BG

79 mg/ml

81 mg/ml

0.006

CHOL

157 mg/ml

162.50 mg/ml

0.022

LDL

84 mg/ml

87.50 mg/ml

0.106

WC: waist circumference. SBP/DBP: systolic/diastolic blood pressure. BG: basal glycemia. CHOL: cholesterol. Mann-Whitney U test. P<0.05.

 
Table 3. Medians of anthropometric, blood pressure and biochemical variables according to the TG/HDL index in adolescents in school from the province of Salta. 2013. CNIN

In Table 4, the multivariate model showed a statistically significant OR for high TG/HDL, strongly associated to being from the interior of the province (3.53), male gender (2.40) and parental history of HTN (2.22) and diabetes (2.40).

Variables

OR

CI

P value

Residence
Capital
Interior


1
3.53



1.62-7.66



0.001

Gender
Female
Male


1
2.40



1.05-5.46



0.037

Student nutrition state
N/M
Ow/Ob


1
3.05



1.56-5.97



0.001

Parental history HTN
NO
YES


1
2.22



1.14-4.39



0.019

Parental history DM
NO
YES


1
2.40



0.99-5.80



0.053

N/M:normal/malnutrition.Ow/Ob:overweight/obesity.HTN:hypertension. P<0.05.

 
Table 4. Multivariate logistic regression model for the TG/HDL index

 

DISCUSSION
There is a growing interest in the identification of cardiovascular risk factors in the early stages of life, because the increase of BMI, the altered homeostasis of glucose and high blood pressure in childhood and adolescence are associated to a high risk of developing obesity, hypertension and coronary artery disease in adulthood [12].

Metabolic syndrome is an association of cardiovascular risk factors that are grouped in a single individual, the link of which is resistance to insulin. This can be measured directly or through the so-called surrogate markers, of which the TG/HDL ratio has been proposed as one of the most accurate [13].

The clinical and prognostic significance of the TG/HDL ratio in the pediatric population is unclear currently. Weiss et al, recently showed that if this ratio is evaluated in adolescence, it predicts a pro-atherogenic profile in adulthood, regardless of the increase in weight [14]. On the other hand, some studies established a predictive relation to heart disease, as was shown by the MS and hypertension association in the MESYAS study (Metabolic Syndrome in Active Subjects in Spain) [15].

In the population of teenagers from Salta, the overweight/obesity association with MS was observed in a previously published paper [16] and in other investigations [17,18] with conclusive results that show the danger entailed by an increase in weight.

In the present study, the prevalence of the TG/HDL index in the teenagers with overweight/obesity was 22.2% lower than that found by Armoa et al, in Misiones (38.5 and 39.2%)[19]. Further, bivariate analysis showed significant associations between the presence of MS (OR 15.91; CI: 6.98-36.29, p=0.000) and some of its components (systolic pressure OR 2.30, CI: 1.41-3.75, p=0.001; waist circumference: OR 2.33, CI: 1.28-4.24, p=0.008) with a high TG/HDL index. Also, when comparing the medium values of systolic BP, BMI, WC, basal glycemia and CHOL, they were significantly higher in teenagers with a high TG/HDL index. Similar results are described by Oliveira et al, in a study made in students from Bahía, Brazil, in whom the averages of BMI, WC, systolic/diastolic BP and CHOL were higher in the group with high TG/HDL, but with a cut-off point of 2.7[20].

The greater prevalence of the TG/HDL index (15%), found in the adolescents from the periurban area of the interior of the province, could be related to changes in eating habits, and low levels of physical activity, as a consequence in recent years of a rapid urbanization and technological changes [3]. Obesity and an altered lipid profile have been associated to urban populations in comparison to rural ones, although they are also increasing in the latter, especially in countries with economic growth [21]. In previous publications, a different biochemical profile was observed in the adolescents of the province of Salta, according to the place of residence; in the Capital city the prevalence and average levels of high CHOL and LDL was greater when compared to the groups from the interior of the province; in the latter group, the profile was associated to a higher prevalence and higher average values of TG and basal glycemia and low values of HDL [3], matching with the greater prevalence of the TG/HDL index with an OR of 3.53 that arises from the multivariate model, which associates the greater risk of this index to being a teenager in school in the interior of the province of Salta.

Family history of HTN and diabetes (in the mentioned model) are associated to a greater probability of a high TG/HDL index (OR 2.2 and 2.4), probably by the significant prevalence found of overweight/obesity in the parents, supporting the idea of an “obesogenic family”, suggesting the existence of environments created by paternal behaviors that contribute to the development of overweight and co-morbidities in children and teenagers [22]. In regard to this, Ventura et al, described profiles of metabolic risk during adolescence and identified family history in a sample of girls, in a longitudinal follow-up. The sample was grouped according to factor values for MS. As a result, they observed that the groups with hypertension and higher risk of MS, presented significantly more family history of type 2 Diabetes and obesity [23].

 

CONCLUSIONS
In the province of Salta, in the studied samples, the TG/HDL index was significantly associated to the nutrition state and the family history of hypertension and diabetes, with different profiles according to gender and place of residence.

This index is easily applied and could be useful to measure the metabolic risk associated to obesity in teenagers.

 

ACKNOWLEDGEMENT
A special acknowledgement to the staff (nurses, lab technicians and epidemiologists) from the Centro Nacional de Investigaciones Nutricionales that helped with the field work, gathering data and evaluating the students. Without their help, this project would not have been made.

 

BIBLIOGRAPHY

  1. Encuesta Nacional de Factores de Riesgo. Disponible en www.msal.gov.ar/htm/Site/enfr/resultados.asp
  2. Encuesta Nacional de Nutrición y Salud. Síntesis Informativa de la Región del Noroeste. Dirección Nacional de Salud Materno infantil. Ministerio de Salud y Ambiente de la Nación.2004-2005. [Acceso: 5-4-2010] Disponible en:
    www.msal.gov.ar/htm/Site/ennys/Sitedefaul
  3. Gotthelf SJ, Jubany LL. Perfil antropométrico y bioquímico de adolescentes escolarizados de la Provincia de Salta, según variables sociodemográficas. Año 2011. Actualización en Nutrición 2012; 13 (3): 191-201.
  4. Gotthelf SJ, Jubany LL. Prevalencia de factores de riesgo cardiovascular en adolescentes de escuelas públicas y privadas de la ciudad de Salta, año 2009.Arch Argent Pediatr2010;108(5): 418-26.
  5. Freedman DS, Khan LK, Dietz WH, Srinivasan SR, et al. Relationship of childhood obesity to coronary heart disease risk factors in adulthood: the Bogalusa heart study. Pediatrics 2001;108(3):712-8.
  6. Gotthelf SJ, Mendes da Fonseca M. Hipertensión arterial y su asociación con variables antropométricas en adolescentes escolarizados de la ciudad de Salta (Argentina).Rev Fed ArgCardiol2012; 41(2): 96-102.
  7. McLaughlin T, Reaven G, Abbasi F, et al. Is there a simple way to identify a individuals con in- creased risk of cardiovascular disease?. Am J Cardiol2005; 96: 399-404.
  8. Zimmet P, Alberti KG, Kaufman F, et al. IDF Consensus Group. The metabolic syndrome in children and adolescents.An IDF consensus report.Pediatr Diabetes 2007; 8: 299-306.
  9. The WHO Childgrowth Standars.Disponible en: www.who.int/childgrwth
  10. BMI Classification2009.Disponible en: www.apps.who.int/bmi/index jsp
  11. Guía para la evaluación del crecimiento físico. Sociedad Argentina de Pediatría. Comité Nacional de Crecimiento y Desarrollo.2013
  12. Dietz WH. Health consequences of obesity in youth: Childhood predictors of adult disease.Pediatrica1998; 101 (Suppl 2): 518-25.
  13. McLauguin T, Abbasi F, Cheal K, et al. Use of metabolic markers to identify overweght individuals who are insulinresistant.AnnIntern Med 2003; 139: 802-9.
  14. Weiss R, Otvos JD, Sinnreich R, et al. The triglyceride to high-density lipoprotein-cholesterol ratio in adolescence and subsequent weight gain predict nu- clear magnetic resonance-measured lipoprotein subclasses in adulthood. J Pediatr201;158:44-50.
  15. Cordero A,Laclaustra M, León M, et al.Prehypertension is associated with insulin resistance state and not with an initial renal function impairment. A Metabolic Syndrome in active subjects in Spain (MESYAS) Registry Substudy. AJH 2006; 19:189-96.
  16. Gotthelf SJ. Prevalencia de síndrome Metabólico según definición de la International Diabetes Federation (IDF) en adolescentes escolarizados de la provincia de Salta, Argentina.Rev Fed ArgCardiol2013; 42(2): 119-126.
  17. Cook S, Auinger P, Chaoyang L, et al. Metabolic síndrome rates in United States Adolescents, from the National Health and Nutrition Examination Survey, 1999-2002. J Pediatr2008; 152 (2): 165-70.
  18. Moraes ACF, Fulaz CS, Netto-Oliveira ER, et al. Prevalência da síndrome metabólica em adolescentes: umarevisão sistemática. CadSaude Pública2009; 25 (6): 1195-1202.
  19. Armoa N, Castillo Rascón MS, López MS, et al. Síndrome metabólico y alteraciones lipídicas en niños con sobrepeso y obesidad. RevCiencTecnol2010; 12 (14): 19-24.
  20. Oliveira AC, Oliveira AM, Oliveira N, et al. Is trygliceride to high-density lipoprotein colesterol ratio a surrogates for insuline resistance in youth?.Health 2013; 5 (3): 481-5.
  21. Uauy R, Albala C, Kain J. Obesity Trends in Latin America: Transiting from Under-To Overweight. JNutr2001; 131:893S-9S
  22. Davison KK, Birch LL. Obesogenic families:parents’physical activities and dietary intake patterns predict girls risk of overweight. Int J ObesRelatMetabDisord2002;26: 1186-93.
  23. Ventura AK, Loken E, Birch LL.Risk profiles for Metabolic Syndrome in a nonclinical sample of adolescents girls. Pediatrics 2006;118(6): 2434-42.

 

Publication: March 2014

 
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