Home > June - Volume 33 - Issue > Relationship Between Body Mass Index (BMI) and Blood Pressur The combination of blood pressure and Body Mass Index (BMI) contribute more than 60% cases of cardiovascular disease. To determine the relationship between Body Mass Index (BMI. Your blood pressure is a good indication of the health of your cardiovascular system. When your blood pressure is high, your heart is working under stressful. However, little longitudinal studies reported BMI in relation to the risk for hypertension among children in China. We examined the longitudinal.
The prevalence for overweight in was However, the prevalence of stunting and thinness among Chinese children and adolescents aged 5—19 years has reached This novel and complex problem challenges governments and health organizations to tackle opposite ends of the malnutrition spectrum. The dual burden may manifest within a community, household, or individual, but these different levels have not been addressed collectively [ 4 ].
Increasing evidence suggests that this epidemic of childhood obesity was causing premature onset of hypertension, resulting in increased risk for adult coronary heart diseases [ 56 ]. The landmark Global Burden of Disease Study showed that the hypertension now tops the list of risk factors for death and disability worldwide [ 7 ].
The prevalence of hypertension increased dramatically from towith average relative increase of 8. Importantly, more and more evidence showed hypertensive children are more likely to develop hypertension in adulthood [ 910 ]. Body mass index BMI is often the measure of thinness and obesity used in some literatures even though it is a ratio of weight to height.
Although some cohort studies have shown that the higher the BMI, the greater the likelihood of developing hypertension in adults [ 11 — 17 ], few longitudinal studies evaluated BMI across the range of thinness and obesity as a primary risk factor. In addition, there were few studies with samples which were powerful enough and a dropout rate low enough in their follow up.
Relationship between body mass index and hypertension
Guangzhou is a big coast city located on the south of China. In this study, we observed the trend of childhood obesity and hypertension development, and thus examined the longitudinal relations between BMI and hypertension in Chinese primary schoolchildren via a retrospective cohort study. Methods and procedures Design and participants The retrospective cohort study was conducted in 54 primary schools from 7 districts in Guangzhou city of China from January until December Participants of the cohort underwent routine examinations approximately every year.
Written informed consent form was obtained from adolescents and their parents. This study was approved by the University Ethical Committee. Percentage distribution of body mass index classification of respondents Click here to view [Figure 2] shows the percentage distribution of BMI classification of respondents according to sex.
Majority of the males were of a normal BMI Females were overweight and obese more than males. Percentage distribution of respondents' body mass index classifications according sex Click here to view [Figure 3] indicates the percentage distribution of BMI classification according to levels of exercise. A low exercise level was observed in this study population. All the underweight and obese respondents did not engage in any exercise. The overweight respondents who exercised were only 3.
Percentage distribution of body mass index of respondents according to level of exercise Click here to view [Figure 4] shows the percentage distribution of BMI classification based on age groups.
BMI was observed to increase with an increase in age. The highest percentage of respondents of a normal BMI across the age groups was Within the 45—50 years' group, the percentage that had a normal BMI was Percentage distribution of body mass index of respondents based on age groups [Table 4] shows the BP profile of participants. Correlation between body mass index and blood pressure of respondents Discussion BMI as a measure of body weight was classified according to the WHO  as underweight, normal, overweight, and obese.
Overweight and obesity are risk factors for many diseases, including high BP. Females had a higher prevalence of overweight and obesity than males. Among the males, 15 7. The prevalence of overweight and obesity in females was 25 This observation is in line with results from literature.
For example, Preedy  observed in a study on BMI and mortality that more women than men were obese in all age groups. This could be due to the fact that men are physically active than women.
It was also found that men work longer hours than women. For instance, 34 Since working is a form of physical activity for most people manual workersit implies that working many hours will help to decrease the risk of becoming overweight or obese. Even among workers in white-collar jobs, working can help to reduce the risk of obesity because working increases energy expenditure since the brain utilizes the energy from food leaving little or none to be stored as fat.
This implies that females are at risk of diseases associated with overweight and obesity, such as Type 2 diabetes mellitus, heart diseases, and stroke than males. Age is a factor that affects the BMI of individuals. Across the age groups, the highest rate of obesity 4.
The increased rate of obesity with respect to an increase in age could be due to the fact that older people are less physically active but maintain the same energy intake as during their earlier years.
Hence, the excess energy that is not expended is stored as fat, increasing their chances of becoming obese. Among these, 35 This observation is expected because similar results were found in literature.
Body Mass Index Relates to Blood Pressure Among Adults
Khurana,  for instance, observed that before menopause, women have a lower SBP than men. The increased incidence of hypertension in males than females could be due to differences in lifestyle. For instance, more men smoke cigarette than women. No female smoke cigarette, but 7 3. Since smoking is a risk factor for high BP, this observation is not surprising. This places men at a greater risk of hypertension and its consequent diseases than women.
Multinomial logistic regression was performed to explain the impact of predictor variables in terms of odds ratios. The value of BMI was calculated and summarized age group wise, and in order to assess BMI-based nutritional status, recommended cut-off points for Asians [ 23 ] were used.
Blood pressure was classified based on JNC 7 [ 24 ]. In Asian subjects, the risk associated with diabetes and cardiovascular diseases occurs at lower levels of BMI when compared with the white population.
This is attributed to body fat distribution; Asian Indians tend to have more visceral adipose tissue, causing higher insulin resistance, despite having lean BMI [ 2526 ]. The mean value for height was found to be highest in the youngest 20—29 years age group.
Mean height decreased in each decade in the successive age groups and lowest mean height was found among the oldest 60—70 years age group. The differences in mean height were statistically significant only between 50—59 yr and 60—70 yr age groups, whereas among the rest of the groups, the differences were statistically non significant.
Body weight increased with age till the age of 49 and decreased thereafter but the differences were statistically significant only between 20—29 yr and 30—39 yr age groups and between 50—59 yr and 60—70 yr age groups. Weight was found to be highest among 40—49 yr age group and lowest among 60—70 yr age group. The overall mean value of all the age groups for height and weight were Table 1 also shows BMI in different age groups.
Maximum value for mean BMI was BMI was found to be lowest among 20—29 yr age group and declined thereafter. The differences in mean BMI was statistically significant between all the age groups except for 40—49 yr and 50—59 yr age groups. The mean value of all the age groups for BMI was found to be Table 2 shows systolic and diastolic blood pressure in different age groups.
Both the mean systolic and diastolic BP were found to be lowest among the youngest age groups. Systolic BP increased steadily with age and the highest was found among the oldest age group. The differences in mean systolic BP between different age groups were statistically nonsignificant.
Diastolic BP increased with age till 40—49 yr and declined thereafter but the differences in mean BP between age groups were statistically nonsignificant with the exception of 20—29 yr and 30—39 yr age groups.
Blood pressure among Tangkhul Naga males in different age groups.
Body Mass Index & Blood Pressure
Lowest numbers of subjects were found in underweight Diastolic BP showed maximum subjects to have normal There were also 5. Minimum mean systolic and diastolic BP were found in underweight category and the maximum systolic and diastolic BP were found among obese category. The mean values of both the systolic and diastolic BP increased from underweight to normal and then to overweight and obese category.
There was also significant positive correlation between age and BMI, but the magnitude of correlation of age with systolic and diastolic BP was more than that of age with BMI. Correlation matrix between BMI, blood pressure, and age. Table 6 displays the odds ratio for predicting systolic and diastolic blood pressure.
Multinomial logistic regression was applied for predicting systolic and diastolic BP using BMI as the independent variable.
BMI as a risk factor for systolic and diastolic blood pressure. Discussion Increasing secular trend in the mean stature was evident from the oldest to the youngest age groups. Improvement in socioeconomic conditions, and better nutrition among the younger subjects could be the reason. The reason for decline in stature in advanced age could also be due to thinning of intervertebral discs as well as flabbiness of muscles, which changes the posture. Aiken [ 27 ] reported that a loss of collagen between spinal vertebrae causes the spine to bow and the height to shrink.
Similar findings have been reported by Kapoor and Tyagi [ 28 ] and Bhardwaj and Kapoor [ 29 ]. The Tangkhul Nagas were small and slender in comparison to the mainland Indian or the western populations. Body weight increased with age till the age of 49 years and slightly decreased after 50 years. The increase in body weight and BMI with age and decline in advanced age has also been reported by Kapoor and Tyagi [ 28 ] and Tandon [ 10 ].
Increase in body weight till middle age may be due to the accumulation of fat with age as the younger subjects have larger appetite leading to increased energy intake, fat-rich diet, and relatively less energy expenditure due to lesser involvement in physical activities. The decline in body weight in more advanced age may be attributed to the decrease in muscle mass in response to reduced amount of protein intake as well as decline in number and size of muscle fibers due to degenerative diseases associated with the advancing age.
It may partly be due to bones becoming lighter because of gradual mineral mass loss [ 30 ]. Systolic and diastolic blood pressures increased with age steadily from the youngest to the oldest age group showing the dependence of BP on age.