The prevalence of overweight and obesity in childhood and adolescence is increasing rapidly worldwide(1–Reference Cole, Bellizzi, Flegal and Dietz3). Epidemiological data show that prevalence rates are increasing not only in industrialised countries but also in developing countries(4), especially as far as the adolescent population is concerned. In general, prevalence rates are higher in adolescents than in childrenReference Livingstone(5), and are also higher among males than females. Overweight and obesity at a young age predicts the likelihood of obesity in adulthoodReference Parsons, Power, Logan and Summerbell(6).
Overweight and obesity at a young age are important risk factors for several disordersReference Kiess, Reich, Muller, Meyer, Galler, Bennek and Kratzsch(7) such as hypertensionReference Burke, Beilin and Dunbar(8, Reference Chu, Wang and Shieh9), early atherosclerotic damageReference McGill, McMahan, Malcolm, Oalmann and Strong(10), cardiovascular diseaseReference Srinivasan, Meyers and Berenson(11–Reference Frontini, Bao, Elkasabany, Srinivasan and Berenson13), metabolic syndromeReference Young-Hyman, Schlundt, Herman, De Luca and Counts(14), the onset of non-insulin-dependent diabetes mellitusReference Pinhas-Hamiel, Dolan, Daniels, Standiford, Khoury and Zeitler(15) as well as morbidity and mortality in later lifeReference Power, Lake and Cole(16, Reference Maffeis and Tato17).
The importance of measuring blood pressure (BP) in childhood has been widely recognised, given that elevated BP levels at a young age may be predictive of early signs of essential hypertension in adulthood. Careful measurements of BP and thorough evaluation of adolescents with sustained high BP should make it possible to identify those who require treatment.
Even though BP levels are positively correlated with height, most authors agree that body mass index (BMI) contributes significantly to BP variability and is the best predictor of BP valuesReference Buonomo, Pasquarella and Palombi(18–Reference Uscategui Penuela, Perez Giraldo, Aristizabal Rivera and Camacho Perez21). In a sample of 155 Native American youths aged 5–18 years, Smith and RinderknechtReference Smith and Rinderknecht(22) showed that mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) increased with increasing BMI percentile. Martinez et al.Reference Martinez, Ibanez, Paterno, De Roig Bustamante, Itati Heitz, Kriskovich Jure, De Bonis and Cáceres(23) revealed a 0·83 mmHg increment in BP for each unit increment of BMI in a sample of 2115 secondary-school students aged 14·8 (standard deviation, sd 1·6) years.
In a sample of 2365 healthy schoolchildren aged 8–16 years, Reich et al.Reference Reich, Műller, Gelbrich, Deutscher, Gödicke and Kiess(24) showed a significant trend towards a higher prevalence of hypertension in subjects with high BMI, but the positive correlation of hypertension to BMI was not only caused by overweight subjects. Indeed, when the high-risk group (above the 90th percentile) was excluded, the trend remained significant. In addition, in a case–control study on 1322 Chinese boys and girls aged 0·1–6·9 years, He et al.Reference He, Ding, Fong and Karlberg(25) found an increase of one BMI unit associated with, on average, an increase of 0·56 mmHg and 0·54 mmHg in SBP and DBP, respectively, for obese children, while in non-obese children, the increase in SBP and DBP was 1·22 mmHg and 1·20 mmHg, respectively.
The significant correlation between BP levels and BMI was also pointed out by Verma et al.Reference Verma, Chhatwal and George(26). Furthermore, these authors investigated which was the best determinant of BP among absolute fat mass, body fat percentage, body fat distribution and BMI, and concluded that BMI was a better predictor of BP than any other measure of body fat in nearly all analyses. In 902 healthy children and adolescents aged 5–18 years, He et al.Reference He, Horlick, Fedun, Wang, Pierson, Heshka and Gallagher(27) found a significant positive relationship between SBP and DBP and trunk fat, adjusted for total fat, in boys by both dual-energy X-ray absorptiometry and skinfold measurements, while in girls trunk fat was not a significant predictor of BP. Lurbe et al.Reference Lurbe, Alvarez, Liao, Tacons, Cooper, Cremades, Torro and Redón(28) studied a sample of 70 obese and 70 non-obese children and adolescents, aged 6–16 years, and found that SBP and DBP were significantly higher among obese subjects, while waist:hip ratio (WHR) was independently associated with SBP. Moreover, the authors pointed out that obese subjects with a predominantly abdominal fat distribution showed higher BP values and concluded that evaluation of body fat distribution in children and adolescents may help to identify subjects more likely to develop hypertension later in life. In addition, using stepwise regression analyses, Smith and RinderknechtReference Smith and Rinderknecht(22) showed that waist circumference, age and BMI were strong predictors for SBP, while waist circumference and age were predictors for DBP in the total sample.
The aim of the present study was to investigate BP levels and their relationship with different body fat indices in a selected group of adolescents in northern Italy, in order to evaluate the prevalence of hypertension in this group of adolescents and plan preventive and corrective strategies.
Methods
Participants
In this cross-sectional study, all students attending the second year of all high schools (n = 17) in the Aosta Valley region (a mainly mountainous zone), northern Italy, were informed about the research protocol (number of subjects = 889 individuals, equal to 0·74 % of the entire population (120 342 individuals) living in Aosta Valley region on 31 December 2001).
The population of the Aosta Valley region is equal to 0·20 % of the Italian population. Five hundred and thirty-two students, 254 males (47·7 %) and 278 females (52·3 %), mean age 15·4 (sd 0·7) years (range 14, 17 years), participated as volunteers in the study.
The study was carried out as part of a wider nutritional surveillance project that also included an investigation, by means of a previously validated questionnaireReference Turconi, Celsa, Rezzani, Biino, Sartirana and Roggi(29), on adolescents’ eating habits and behaviours, nutritional and food safety knowledge and dietary beliefs.
We decided to select only the second-year high-school students, as we intend to follow up the adolescents through their senior year after a preventive and corrective healthy education intervention aimed at promoting lifestyle changes, including achievement or maintenance of normal body weight, dietary habits improvement and increase in physical activity. Of the 17 high schools, nine were located in Aosta town and eight in the countryside. All students were surveyed over the course of four months, from March to the end of June 2002.
The study was carried out with the cooperation of the school teachers’ board and the medical staff of the Aosta Valley Regional Public Health Department. Before starting the study, a number of meetings were organised with teachers and students to explain the aim of the research and to request their participation. Informed written consent was obtained from each student and their parents.
The research protocol was approved by the Ethics Committees of both Pavia University Medical School and the Aosta Valley Regional Public Health Department.
Measurements
Body fat indices measurements
After setting up a classroom in each school to conduct medical assessments, students were examined by trained health personnel (four physicians and one dietitian) who had received 12 hours of instruction and were standardised in assessing measurements. A subset of adolescents (57 subjects) was measured by all personnel to determine intra- and inter-operator variability, which resulted to be <4 % for all the measurements. The following parameters were measured.
• Body weight, measured on subjects wearing only underwear and without shoes, by means of a steelyard scale (precision ±100 g).
• Body height, measured on subjects without shoes by means of a stadiometer (precision ±1 mm).
• Four skinfold thicknesses (mid-triceps, mid-biceps, subscapular and suprailiac), measured on subjects according to standard conditions on the non-dominant body side using a Harpenden skinfold thickness calliper (resolution ±2 mm); three consecutive measurements were performed and the mean of the three values was considered.
• Waist circumference, measured to the nearest mm in duplicate according to standard conditions, by placing a flexible tape midway between the lowest rib and the iliac crest. The tape was snug, but did not squeeze or compress the skin, and was parallel to the floor. The measure was collected on unclothed, relaxed subjects, after exhaling.
• Hip circumference, measured to the nearest mm in duplicate according to standard conditions, at the maximum extension of the buttocks with a flexible tape on the subject wearing only underwear.
BMI was calculated as the ratio between weight (in kilograms) and the square of height (in metres). The sum of the four skinfold thicknesses was computed and the body fat percentage was calculated according to the Weststrate and Deurenberg equationReference Weststrate and Deurenberg(30).
BP measurements
SBP and DBP were measured according to standard conditions on the right arm, with the subject in a supine position and after resting for at least 5 min. Measurements were made by auscultation with the use of a calibrated mercury sphygmomanometer and a cuff appropriately sized for the subject’s arm size. The cuff size was chosen to be as large as possible without having the elbow skin crease obstruct the stethoscope. SBP was determined by the first Korotkoff sound, and DBP by the fifth Korotkoff sound. Three BP measurements were taken at intervals of 3–5 min and the mean of the three values was considered. BP was measured in the supine position because the normal percentiles of Menghetti et al.Reference Menghetti, Virdis, Strambi, Patriarca, Riccioni, Fossali and Spagnolo(31), which we used as reference standard values, were obtained by measuring BP in the same position.
Each student was examined and all measurements were taken during school time; each examination took about 40 min.
Smoking and alcoholic drinking habits and physical activity level
Adolescents’ smoking and alcoholic drinking habits, as well as physical activity level, were also investigated by means of an interview conducted by the trained medical staff after the measurements were taken. The interview was aimed at investigating both the number of cigarettes habitually smoked and the number and kind of alcoholic drinks habitually drunk per day or per week, as well as the number of hours of physical activity practised per day or per week.
Parental investigation
Parental weight and height, for BMI calculation, education and socio-economic levels as well as family history of hypertension were requested from the parents by means of a brief self-administered questionnaire that the students gave to their parents. Familial hypertension history was considered positive for at least one parent suffering from hypertension.
Cut-off values
In accordance with the International Obesity Task Force (IOTF), Cole et al.’s cut-off point reference standards for BMIReference Cole, Bellizzi, Flegal and Dietz(3) were used to identify overweight and obesity in young age. Cole’s percentile curves were drawn so that at age 18 years they passed through the widely used cut-off points of 25 and 30 kg/m2 for overweight and obese adults. The resulting curves were averaged to provide age- and sex-specific cut-off points from 2 to 18 yearsReference Cole, Bellizzi, Flegal and Dietz(3). The IOTFReference Bellizzi and Dietz(32–34) suggests that Cole’s cut-off points are less arbitrary and more internationally based than current alternatives (they were developed by measuring 97 876 males and 94 851 females from birth to 18 years of age living in Brazil, Great Britain, Hong Kong, The Netherlands, Singapore and the USA) and will help to provide internationally comparable prevalence rates of overweight and obesity in children and adolescents.
In accordance with the report of the Fourth NHLBI (National Heart, Lung, and Blood Institute) Task Force on Blood Pressure Control in Children(35), hypertension was diagnosed when the value of SBP and/or DBP was above the 95th reference standard percentile for age and sex, whereas levels between the 90th and the 95th percentile were considered ‘high normal’ (or ‘borderline’ or ‘at risk’). Normal percentiles of Menghetti et al.Reference Menghetti, Virdis, Strambi, Patriarca, Riccioni, Fossali and Spagnolo(31), constructed by fitting a third-order polynomial model of BP on age and height using multiple regression analysis, after BP measurements in 11 519 healthy subjects of both sexes, aged 5–17 years, living in various locations throughout Italy, were used as the Italian reference standards.
Data analysis
Data (mean, sd) were analysed using the Statistical Package for the Social Sciences version 10 for PC (SPSS Inc., Chicago, IL, USA); they were normally distributed and Pearson’s correlation coefficients were computed to analyse relationships between BP values and each of the adiposity indices: BMI, body fat mass, waist and hip circumferences and WHR. Multiple regression analyses with the stepwise method were used to verify the association between BP and the adiposity indices. Student’s unpaired t test was used to compare BP values among very active and sedentary subjects.
Results
BMI and body fat indices
Characteristics of the sample are shown in Table 1. Mean BMI was 21·9 (sd 3·4) kg/m2 and 21·0 (sd 2·9) kg/m2 for males and females, respectively; i.e. in the range of normal-weight subjects. Percentile distribution data indicated that males’ BMI values were higher than those of females: 17·4 kg/m2 and 16·4 kg/m2 at the 5th percentile, 21·2 kg/m2 and 20·7 kg/m2 at the 50th percentile, and 28·9 kg/m2 and 26·4 kg/m2 at the 95th percentile for boys and girls, respectively.
Table 1 Age and anthropometric characteristics of the sample
sd, standard deviation; BMI, body mass index.
*Prevalence of normal weight, overweight and obesity, respectively: 74·0 % (males) and 81·7 % (females), 20·9 % (males) and 14·7 % (females), 4·7 % (males) and 1·1 % (females).
Table 2 lists the mean, sd and 5th, 50th, 95th percentile values of body fat indices for males and females. Four skinfold thicknesses, fat mass percentage, waist and hip circumferences and WHR are provided. All the measurements were statistically different between genders, with P ranging from <0·05 to <0·001, except for hip circumference and WHR values.
Table 2 Adolescents’ body fat indices and percentile distribution
sd, standard deviation.
BP measurements
Table 3 shows the mean, sd and percentile values of SBP and DBP for males and females, compared with the reference standard values for the Italian young population provided by Menghetti et al.Reference Menghetti, Virdis, Strambi, Patriarca, Riccioni, Fossali and Spagnolo(31). Our values were higher than the Italian reference valuesReference Menghetti, Virdis, Strambi, Patriarca, Riccioni, Fossali and Spagnolo(31) in both sexes. The SBP value was between the 50th and 75th percentile in males and between the 25th and 50th percentile in females, while the DBP mean value in both sexes was between the 25th and 50th percentile.
Table 3 Blood pressure measurements obtained in the present study compared with reference standard values of Menghetti et al.Reference Menghetti, Virdis, Strambi, Patriarca, Riccioni, Fossali and Spagnolo(31)
SBP, systolic blood pressure; DBP, diastolic blood pressure; M, males; F, females; sd, standard deviation.
Based on the Fourth Task Force Report cut-off values on hypertension(35), in the overall sample 11·8 % of the adolescents were systolic hypertensive, while 6·9 % were diastolic hypertensive (Table 4). In addition, the distribution of hypertensive adolescents among normal-weight subjects and overweight plus obese subjects for both sexes is provided. In males, the percentage of hypertensive adolescents was higher in the overweight plus obese subjects both for SBP and DBP compared with normal-weight subjects; in females, the percentage of hypertensive subjects was higher in the overweight plus obese subjects for SBP, while for DBP the percentage of hypertensive subjects was higher in the normal-weight subjects than in the overweight plus obese subjects.
Table 4 Prevalence rates of hypertensive subjects by gender and weight status
Relationships between BP levels and adiposity indices
In the linear correlation analysis, BMI and all the adiposity indices, except WHR, were found to be significantly associated (P ranging from 0·05 to 0·001) with both SBP and DBP, with r ranging from 0·152 to 0·359. BMI and body fat mass had the strongest association with BP. Multiple regression analyses showed that BMI was the strongest predictor for SBP in males (P < 0·001, r = 0·275) and females (P < 0·001, r = 0·336). For DBP, body fat mass was the strongest predictor only in males (P < 0·001, r = 0·359).
Parental investigation
Adolescents’ BMI correlated positively to the same extent with both the father’s (P < 0·01) and the mother’s (P < 0·01) BMI in males and females, with r values equal to 0·23 and 0·24, respectively. While BMI did not show a significant correlation with parental socio-economic and educational levels, it nevertheless showed a positive trend towards both parental low educational and low socio-economic levels. On the other hand, both SBP and DBP values showed no correlation or trend with parental BMI, education or socio-economic level. A positive trend emerged between BP levels (either SBP or DBP) and a positive history of familial hypertension (data not shown).
Smoking and alcoholic drinking habits and physical activity level
Only 26 subjects (4·9 % of the sample) reported being current smokers; therefore, no correlation could be carried out between BP values and smoking.
Regarding alcoholic drinking habits, only 45 subjects (8·4 %) reported being habitual consumers of two glasses of wine per day, while the consumption of other alcoholic drinks was occasional. Therefore, the number of drinking subjects was too small to carry out statistical analyses.
Finally, lower BP values emerged in very active subjects (practising physical activity for 6 h or more per week, 18·5 % of subjects) compared with those measured in sedentary subjects (practising no habitual physical activity, 29·7 % of subjects), but without any significant difference. Nevertheless, a negative trend was observed between both SBP and DBP levels and increasing physical activity practice.
Discussion
BMI data show the high prevalence of overweight subjects in both sexes, although our data are lower than those found in southern ItalyReference Grispan, Toselli, Fabiani, Bontempo, Liberatore, Gagliardi and Tarsitani(36–39), consistent with a higher prevalence of overweight and obesity in that area. As far as body fat mass percentage is concerned, our data are higher than those reported by Schaefer et al.Reference Schaefer, Georgi, Wuhl and Scharer(40) in a German adolescent population (12 % body fat mass for males, 21 % for females) and also those reported by EllisReference Ellis(41) in a Caucasian male adolescent population (14·8 %), supporting a greater risk, mainly for males, to develop obesity, as already revealed by the higher prevalence rates of overweight and obesity in this gender.
Such a high percentage of overweight subjects is a public health threat; preventive and counteractive strategies need to be undertaken in school programmes aimed at reducing this risk condition.
With regard to body circumferences, our data are higher than those reported by other researchers in same age groups. In British adolescents waist circumference values were 70·8 (sd 7·1) cm in males and 64·9 (sd 4·9) cm in femalesReference McCarthy, Jarrett and Crawley(42). In Cuba the 50th percentile waist circumference values were equal to 68 cm for males and 64 cm for femalesReference Martinez, Devesa, Bacallao and Amador(43). On the other hand, our data are supported by studies carried out in the USAReference McCarthy, Jarrett and Crawley(42) and SpainReference Moreno, Fleta, Mur, Rodriguez, Sarria and Bueno(44) (50th percentile waist circumference values equal to 74 cm for males and 69 cm for females), showing that our population is more similar to these ones.
The present SBP and DBP values are higher (Table 5) than those reported as Italian reference standardsReference Menghetti, Virdis, Strambi, Patriarca, Riccioni, Fossali and Spagnolo(31) for a young population aged 15 years. Concerning Menghetti et al.’s dataReference Menghetti, Virdis, Strambi, Patriarca, Riccioni, Fossali and Spagnolo(31), they show that Italian children’s and adolescents’ BP levels are slightly higher than those of Americans, in contrast with the belief that Italian people are protected against cardiovascular risk factors, including hypertension, more than other populations.
Table 5 Mean blood pressure values in the present sample compared with those found in other adolescent groups
SBP, systolic blood pressure; DBP, diastolic blood pressure; M, males; F, females.
*50th percentile values.
Our values are higher than those found some years ago by Maida et al.Reference Maida, Mura, Muresu and Romano(45) in Sardinian adolescents aged 11–15 years and higher than those reported by Paradis et al.Reference Paradis, Lambert, O’Loughlin, Lavallee, Aubin, Delvin, Levy and Hanley(46) in Canadian adolescents aged 16 years. On the other hand, they are quite similar to those found in 1526 Belgian adolescentsReference Paulus, Saint-Remy and Jeanjean(47), aged 12–17 years, who had been selected from a high cardiovascular risk population. Even the 50th percentile values are higher than those reported in Brazilian adolescents of the same ageReference Pozzan, Brandao, Da Silva and Brandao(48).
The SBP and DBP 90th percentile values found in males in the present study are higher than those in the USAReference Menghetti, Virdis, Strambi, Patriarca, Riccioni, Fossali and Spagnolo(31) (128/79 mmHg) and in northern EuropeReference Menghetti, Virdis, Strambi, Patriarca, Riccioni, Fossali and Spagnolo(31) (137/77 mmHg) in the same age group, while in females they are similar (126/80 mmHg in the USAReference Menghetti, Virdis, Strambi, Patriarca, Riccioni, Fossali and Spagnolo(31) and 130/76 mmHg in northern EuropeReference Menghetti, Virdis, Strambi, Patriarca, Riccioni, Fossali and Spagnolo(31)). In males, the SBP 90th percentile value is particularly high (140 mmHg); it is even equal to the value considered as an indicator of first-degree hypertension in the adult population. These values in males may be due to the high prevalence rates of overweight and obesity, as well as the high values of adiposity indices, which are well-known risk factors for hypertension.
The prevalence rates of systolic and diastolic hypertensive adolescents are high, but they are mostly related to SBP (11·8 % of subjects). Comparison of our data with others’ (Table 6) shows higher values than those in adolescent populations of different ages and in different geographical areasReference Martinez, Ibanez, Paterno, De Roig Bustamante, Itati Heitz, Kriskovich Jure, De Bonis and Cáceres(23, Reference Menghetti, D’Addesa, Censi, Spagnolo, Martone, Cellitti and Sette49–Reference Mohan, Kumar, Aslam, Rangbulla, Kumbkarni, Sood and Wander52).
Table 6 Prevalence rates of systolic hypertensive adolescents (males plus females) in the present sample compared with those found in other young groups
sd, standard deviation.
*In urban/rural areas.
†Age range (years).
Higher prevalence rates of hypertensive adolescents in overweight plus obese subjects (Table 4), when compared with normal-weight subjects, support previous findingsReference Buonomo, Pasquarella and Palombi(18–Reference Martinez, Ibanez, Paterno, De Roig Bustamante, Itati Heitz, Kriskovich Jure, De Bonis and Cáceres23, Reference Burke, Beilin, Dunbar and Kevan53) reporting that high BMI values are a predisposing factor in the development of hypertension. Nevertheless, the percentage of hypertensive subjects found even in the group of normal-weight subjects, consistent with other studiesReference Reich, Műller, Gelbrich, Deutscher, Gödicke and Kiess(24, Reference He, Ding, Fong and Karlberg25), shows that hypertension is an under-recognised clinical entity in children and adolescents, while monitoring of BP levels might help in detecting occult hypertension at a young age and limiting the magnitude of cardiovascular risk. Indeed, hypertension is the most common form of cardiovascular disease and it is often associated with overweight and obesity. Although it is less common in adolescents than in adults, hypertension and the associated organ damage can and often do begin early in life. Unless reversed, this condition could determine cardiovascular disease outcome in adulthood. Consequently, for many with high BP levels, measures directed at the long-term prevention of cardiovascular morbidity may need to be started in adolescence to achieve maximal effectiveness.
Even though BMI and all the adiposity indices were found to be significantly associated with BP levels in both sexes, BMI and body fat mass showed the strongest association, most closely related to SBP in both genders and to DBP only in males, in agreement with the literature data indicating that BMI contributes significantly to BP variabilityReference Leccia, Marotta, Masella, Mottola, Mitrano, Golia, Capitanata, Guida, Contaldo and Ferrara(19–Reference Uscategui Penuela, Perez Giraldo, Aristizabal Rivera and Camacho Perez21, Reference Reich, Műller, Gelbrich, Deutscher, Gödicke and Kiess24, Reference He, Horlick, Fedun, Wang, Pierson, Heshka and Gallagher27, Reference Paradis, Lambert, O’Loughlin, Lavallee, Aubin, Delvin, Levy and Hanley46), even in non-obese subjectsReference Reich, Műller, Gelbrich, Deutscher, Gödicke and Kiess(24, Reference He, Ding, Fong and Karlberg25).
The correlation between parental and adolescents’ BMI values supports previous findingsReference Buonomo, Pasquarella and Palombi(18, Reference Krassas, Tzotzas, Tsametis and Konstantinidis54–Reference Burke, Beilin and Dunbar56) showing an influence of both parents’ BMI on their children. In particular, the results are in agreement with the data obtained in a previous study carried out in southern ItalyReference Esposito-Del Puente, Scalfi and De Filippo(57) in which children’s BMI correlated with both fathers’ and mothers’ BMI to the same extent.
Although no significant correlation between adolescents’ BMI and parental socio-economic and education levels emerged, a positive trend was found showing that these factors may influence weight condition, as reported by other authorsReference Krassas, Tzotzas, Tsametis and Konstantinidis(54, Reference McMurray, Harrell, Deng, Bradley, Cox and Bangdiwala58). In addition, adolescents’ risk of becoming overweight increased with parental overweight and obesity, thus showing that familial condition (genetics, unhealthy dietary habits together with a sedentary lifestyle) has to be taken into account to identify risk groups for preventive measures. It is interesting to point out that foods such as cheese rich in fats, salami, sausages, butter and lard are traditional components of local meals in this region (data not presented).
Parental BMI does not seem to influence children’s BP levels in our sample; it is more likely that parental history of hypertension, rather than parental BMI, may influence children’s BP levels since a positive trend emerged between students’ BP levels and a positive history of familial hypertension. Neither parental socio-economic level nor education level influenced children’s BP levels in our study.
The data reported by the students about smoking are doubtful since a recent investigation(59) showed an increase of smokers among adolescents aged 14–16 years equal to 33 % in males and 69 % in females during a six-year period (1993–1999).
The fact that 45 subjects report being habitual consumers of two glasses of wine per day is not surprising, since alcohol consumption is widespread in this region, while we expected more physical activity practice in a mainly mountainous zone. Despite this, a negative trend was observed between BP levels and increasing physical activity practice, confirming the positive role of habitual physical activity in preventing hypertension.
Conclusion
The limitation of this study arises from the fact that we examined subjects of a selected age group and therefore the results may not be extended to a wider range of adolescents, even though we explained the reason for our choice.
The high values of BP and hypertension rates, together with high prevalence of overweight plus obese subjects found in our sample, are worrying. There is a pressing need to develop a comprehensive medical and nutrition plan together with preventive and corrective strategies in school programmes to reduce the prevalence of these identified disease states, by empowering teens to increase physical activity and to improve their own dietary habits together with their lifestyle.
Acknowledgements
The authors of this paper state that: there are no financial or other contractual agreements that might cause conflicts of interest; the research obtained funding from the Italian Ministry of Health; and each author has participated actively in the work and has given substantial contribution: G.T. – project of the study, data analysis and supervisor; R.B. – supervisor in the assessment of anthropometric measurements; L.M. – statistical analysis; C.R. – supervisor. The Italian Ministry of Health is thanked for funding the research.
