Reviewing of the Relationship Between Body Mass Index and High Blood Pressure of Patients

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1 Iteratioal Joural of Statistics ad Actuarial Sciece 207; (): doi: 0.648/j.ijsas Reviewig of the Relatioship Betwee Body Mass Idex ad High Blood Pressure of Patiets Ishaq Olawoyi Olatuji, *, Akeem Ajibola Adepoju, Abdulmuahymi Abiola Sausi 2, Audu Ahmed 3 Departmet of Statistics, Kao Uiversity of Sciece ad Techolog, Wudil, Nigeria 2 Departmet of Mathematics ad Computer Sci., Uiversity, Kashere, Gombe, Nigeria 3 Departmet of Mathematics, Usmau Dafodiyo Uiversity, Sokoto, Nigeria address: babigto4u@gmail.com (Ishaq O. O.) * Correspodig author To cite this article: Ishaq Olawoyi Olatuji, Akeem Ajibola Adepoju, Abdulmuahymi Abiola Sausi, Audu Ahmed. Reviewig of the Relatioship Betwee Body Mass Idex ad High Blood Pressure of Patiets. Iteratioal Joural of Statistics ad Actuarial Sciece. Vol., No., 207, pp doi: 0.648/j.ijsas Received: February 28, 207; Accepted: March 22, 207; Published: April 7, 207 Abstract: O average, older adults ted to have more body fat tha youger adults for a equivalet BMI. Hece, few works have bee carried out o the areas of relatioship betwee Body Mass Idex ad Hypertesio. Therefore, this research is carried out to review the relatioship betwee Body Mass Idex ad patiets with high Blood Pressure at Murtala Muhammad specialist hospital kao state usig regressio ad correlatio aalyses. The result shows that the coditios of patiets with high blood pressure are worseed by excess weight, also the relatioship betwee body mass ad systolic ad that of diastolic blood pressure were assed to be strog ad fairly weak respectively. Keywords: Body Mass Idex, Diastolic Blood Pressure, Systolic Blood Pressure ad Height. Itroductio The body mass idex (BMI) or Quetelet idex is a value derived from the mass (weight) ad height of a idividual. The BMI is defied as the body mass divided by the square of the body height, ad is uiversally expressed i uits of Kg/m 2, resultig from mass i kilograms ad height i meters. The BMI is attempt to quatify the amout of tissue mass (muscles, fat ad boe) i a idividual ad the categorize that perso as Uderweight, ormal weight, or obese based o that value. However there is some debate about where o the scale the dividig lies betwee categories should be placed. Obesity rates have bee icreasig over recet decades, causig sigificat Cocer amog policy makers. Excess body fat, commoly measured by body mass Idex(BMI), is a major risk factor for several commo disorders icludig diabetes ad cardiovascular disease, placig a substatial burde o health care systems. To guide effective public health actio, we eed to uderstad the complex system of itercorrelated iflueces o BMI. Mulatero [] says Persistece hypertesio is oe of the risk factors for stroke, heart attacks, heart failure ad arterial aeurysm ad is a leadig cause of chroic kidey failure. Moderate elevatio of arterial blood pressure leads to short life. [2] Adolescet obesity is o the rise ad is associated with adverse health effects. Excessive body weight, icludig overweight ad obesity, together with hypertesio, represets major threats to civilizatio i the 2st Cetury. [3] However, the impact of weight gai o BP is either cosistet across age groups, or is it the same betwee me ad wome. [4] Subcutaeous abdomial tissue was more cosistetly related to CVD risk tha peripheral ski folds. Liear correlatios betwee both SBP ad DBP for all athropometric measuremets amog males were foud to be sigificat i the adult Brazilia me ad blood pressure icreased with higher BMI, WC, ad various ski fold locatios. [5] a icrease i the dimesio of this problem has bee reported i the high socio-ecoomic group i Idia. A study i Delhi revealed eve higher prevalece (32-50%)

2 20 Ishaq Olawoyi Olatuji et al.: Reviewig of the Relatioship Betwee Body Mass Idex ad High Blood Pressure of Patiets of overweight (body mass idex (BMI) >25) amog adults belogig to high icome group as compared with % i those belogig to middle icome group. The possibilities of various dietary factors, such as reductios i the salt cotet of food, have also bee cosidered i prevetig hypertesio [6]. Other utritioal meas of lowerig blood pressure are the icrease itake of high protei diets, traditioal diet that cosists of a variety of fermeted soybea products ad vegetable based foods, which are rich sources of bioactive compouds (such as hesperidig) capable of promotig cardiovascular health [7]. Other researchers [, 8-4] have show a positive relatioship betwee overweight, obesity, uhealthy lipid profiles, high isuli levels, ad hypertesio i both childre ad adolescets, ad abstiece from the cosumptio of processed red meat treated with high sodium ad itrites [5]. Hypertesio ad overweight could therefore be subjects of major public health cocer i Kao State, showig that the itesive medical educatio about ways to mitigate ad prevet hypertesio i the regio is of a great importat. There are growig evidece that beig overweight, or obese has effect i other aspects of life such as health status, job commitmet ad academic performace. The rise i body size mostly i developed societies amog school age childre makes the latter particularly pertiet. 2. Materials ad Methodology 2.. Regressio Regressio is the techiques used to study the relatioship betwee variables. Liear regressio is used for a special class of relatioship, those that ca be described by straight lie. The liear regressio techique is applicable i every field of study, such as maagemet sciece, biological scieces, physics, medical scieces, agricultural sciece ad the humaities ad so o. The purpose of fittig a liear regressio model is as varied as its applicatios, but the most commo oes are the descriptios of a relatioship ad the predictio of future variables. The method of least square ca be used to estimate the values of the ukow parameters of the regressio model i such way that this least square estimate whe fitted to the model provides a lie of best of fit to the data. Sice the first step i regressio is to assume that the relatioship betwee the depedet ad idepedet variable ca be fitted by a liear model. Due to the above reaso, we the fit a model to the observatios. Now let us cosider a liear model below: = + + () It is called simple liear regressio model, because it has oly oe idepedet variable or regressor. Where Y i is the respose variable or depedet variable β 0 is the itercept term β is the slope coefficiet is the radom error term or disturbace term i.e., the distace of idividual Y from the regressio lie, β 0 is the itercept, the value of Y whe X =0 ad the β, is the slope of the lie i.e. the rate of chage i Y for a uit chage i X. β 0 ad β are called populatio parameters, which ca be estimated usig the least square method sice they are ukow. The least square estimators of the itercept ad slope i the simple liear regressio model are: β = Y β X (2) 0 β = XY XY i i X X 2 2 i Where yi Y = ad xi X = The fitted or estimated regressio lie is therefore; Correlatio Coefficiet r (3) ŷ= ˆ β + ˆ β x (4) Whe two cotiuous variables are measured i the same perso, such as weight ad height, systolic ad diastolic blood pressure, the relatioship betwee the two quatitative measuremet or cotiuous variables is called correlatio. The degree or the magitude of associatio betwee two sets of figures o cotiuous variables such as height ad weight is measured i terms of a parameter called correlatio coefficiet. It is deoted by R. The extet of correlatio rages betwee (-) ad (+) ad the formula for calculatig correlatio coefficiet betwee two Variables say X ad Y o subject is: r = xy x y [ x ( x) ][ y ( y) ] Where x is the idepedet variable, y is the depedet variable ad is the umber of observatio. It varies from r = 0 which suggests there is o relatioship existig betwee the variables, r = which suggests a perfect positive liear correlatio or r = - which suggests a perfect egative liear correlatio. The correlatio coefficiet (r) is usually reported i terms of its squared (r 2 ), which is iterpreted as percet of variace Data Collectio The data used for this project was a secodary data, ad was obtaied from medical record departmet, Murtala Muhammad specialist hospital, Kao state. (5)

3 Iteratioal Joural of Statistics ad Actuarial Sciece 207; (): Aalysis ad Discussios This sectio deals with the Aalysis ad Discussio of the collected data cosidered i the research work. Two liear models were used for testig relatioship betwee the variables. 3.. Aalysis of Body Mass Idex VS Systolic Blood Pressure Table. Estimatio of Parameters. Predictor Coef SE Coef T P Costat BMI X S = R-Sq = 6.% R-Sq(adj) = 4.% From above table, it is shows that the percetage of coefficiet of determiatio is low so therefore due to the weak relatioship betwee the depedet variable (systolic) ad the idepedet variables (body mass idex), the idepedet variables explaied the depedet variable by oly 6.%, while the remaiig 93.9% is explaied by some other factors. Also the two coefficiets β =28 is sigificat while β i =0.979 is ot sigificat from zero, sice the p-value is greater tha level of sigificat ( =0.05). The regressio equatio is Systolic = BMI Table 2. Sigificat Differece Betwee Systolic ad BMI. Source DF SS MS F P Regressio Residual Error Total Table 4. Sigificat Differece Betwee Diastolic ad BMI. Source DF SS MS F P Regressio Residual Error Total Sice the p=0.4 value > =0.05, we accept H 0 which said that there is o sigificat relatioship betwee BMI ad Diastolic of patiet with high blood pressure. Acceptig of H 0 leads to rejectig H which said that there is sigificat relatioship betwee BMI ad Diastolic of patiet with high blood. The regressio equatio is Diastolic = BMI(x) Table 5. Correlatio Coefficiet betwee BMI, Systolic ad Diastolic. Variables Systolic BMI BMI P-value Diastolic P-value From the table above, there exist fair relatioships betwee the systolic blood pressure ad the body mass idex ad that of diastolic blood pressure ad the body mass idex, sice the p values > α -value. Hece, there are o sigificat relatioships betwee BMI ad Systolic blood pressure ad that of BMI ad Diastolic blood pressure. While there is a sigificat relatioship betwee Diastolic ad that of Systolic blood pressures. Sice p=0.085 =0.05 we accept H 0 which said that there is o sigificat relatioship betwee BMI ad Systolic of patiet with high blood pressure. Acceptig of H 0 leads to rejectig of H which said that there is o sigificat relatioship betwee BMI ad Systolic of patiet with high blood. It implies that there is o sigificace Aalysis of Body Mass Idex VS Diastolic Blood Pressure Table 3. Regressio Aalysis o Diastolic versus BMI. Predictor Coef SE Coef T P Costat X S = R-Sq = 4.5% R-Sq(adj) = 2.5% Figure. Plot of Systolic, Diastolic ad BMI. The graph above shows there is fair relatioships betwee Systolic vs. BMI ad Diastolic vs. BMI. From table above, it shows that the percetage of coefficiet of determiatio is low so therefore due to the poor relatioship betwee the depedet variable diastolic ad the idepedet variables body mass idex, the idepedet variables explaied the depedet variable by oly 4.5%, while the remaiig 95.5% is explaied by some other factors. The two coefficiets β are sigificat ad β are ot sigificat, sice it p-value =0.4> 0.05 level of sigificat. Figure 2. Plot of Correlatio Coefficiet for Systolic ad Diastolic.

4 22 Ishaq Olawoyi Olatuji et al.: Reviewig of the Relatioship Betwee Body Mass Idex ad High Blood Pressure of Patiets 4. Discussios From the study ad aalysis carried out, it has bee observed that the coditio of patiets with high blood pressure is worseed by excess weight ad i order for them to become ormal they eed to work o their weight. The level of salt itake ad alcohol cosumptio were ot assessed i this study. Also the diagosis of hypertesio was made based o the two blood Pressure measuremets at a sittig. This may have affected the overall prevalece. The models showed the relatioship betwee body mass ad systolic blood pressure was strog while o diastolic was fairly weak ad the coefficiet of determiatio for the systolic was 6.% which cotributes more tha the diastolic pressure with low percetage. The idepedet variable (BMI) cotributed sigificatly to the level of blood pressure of patiets (Systolic) as show by the coefficiet of BMI i table. This implies that, icrease i BMI may lead to rise i blood pressure (Systolic). The F-statistic which is said to test the geeral sigificace of the regressio revealed that estimated model ca be accepted. The prelimiary ivestigatio of the relatioship betwee the two variables (BMI ad blood pressure) usig the scatter diagram is suggestive of direct liear relatioship. That is, whe BMI icreases, the blood pressure icreases, it shows i the figure 2. Ad the relatioship betwee Systolic blood pressure ad BMI is sigificace while that of diastolic blood pressure ad BMI is ot sigificat which lead to rejectio of alterative hypothesis for the diastolic pressure. Ad it has bee proved that there exist relatioship betwee Systolic blood pressure ad Diastolic blood pressure. 5. Coclusios Obesity measured i terms of body mass idex has bee used as the predictor for Hypertesio; though BMI is the most commo, it may ot accurately assess obesity o differet patiets. This work attempted to capture the true relatioship of blood pressure ad BMI. We were maily iterested i the sigificace of BMI as a predictor of blood pressure ad the fuctioal form of BMI ad blood pressure. The results revealed that BMI has a impact o the level of blood pressure ad this falls i lie with what have bee metioed i above literature reviews. This study showed that a decrease i BMI has a beeficial effect o blood pressure. We suggest that cliicias look for obesity coexistig with hypertesio, ad treat such cases to avoid coroary evet ad other complicatios of hypertesio. Prevetio ad cotrol of hypertesio has a sigificatly positive impact o the life expectacy. Therefore, weight loss may cotribute positively i maagig the problem of hypertesio. Recommedatios The followig are recommeded i order for the patiets to become ormal:- i. Watch ad cotrol their food itake by eatig more fruits, vegetables, food that cotai more fiber ad vitami D, eatig more fish ad avoid much alcohol itake. ii. They should egage themselves i regular aerobic exercise. iii. Visit the cliic more frequetly ad take atihypertesive drugs. Area for Further Research It is hoped that this research iflueces others to replicate this work, possibly usig other methods. Oly whe oe is willig to questio our curret practice ca oe be able to improve o it. Sice o-liearity was foud betwee diastolic blood pressure ad BMI, a better method should be used whe modelig the relatioship. A ivestigatio of the compariso betwee efficiecy of fractioal Polyomials ad o-parametric methods to determie the best method for modelig the relatioship betwee blood pressure ad body mass idex. Refereces [] Mulatero, P, Bertello c ad Verhovez, A. (2009) differetial diagosis of primary aldosteroism subtypes curret hypertesio reports. [2] Itagi V, Patil R. (20). Obesity i childre ad adolescets ad its relatioship with hypertesio. Turk J Med Sci. 4: [3] Halper A, Macii MC, Magalhaes MEC, Fisberg M, Radomiski R, Bertolami MC (200). Metabolic sydrome, dyslipidemia, hypertesio ad type 2 diabetes i youth: from diagosis to treatmet. Diab Metab Sydr; 2: 55. [4] Wag H, Cao J, Li J, Che J, Wu X, Dua X, (200). Blood pressure, body mass idex ad risk of cardiovascular disease i Chiese me ad wome. BMC Public Health. 0: 89. [5] Srikath J, Jayat Kumar K, Narasimha NS (20). Factors ifluecig obesity amog urba high school childre Bagalore City. Idia J Nutr Dietet. 48: 8 7. [6] Peg YG, Li W, We XX, Li Y, Hu JH, Zhao LC. (204). Effects of salt substitutes o blood pressure: a meta-aalysis of radomized cotrolled trials. Am J CliNutr; 00: [7] Jug SJ, Park SH, Choi EK, Cha YS, Cho BH, Kim YG. (204). Beeficial effects of korea traditioal diets i hypertesive ad type 2 diabetic patiets. J Med Food; 7: 6-7 [8] Nielse GA, Aderse LB. (2003). The associatio betwee high blood pressure, physical fitess, ad body mass idex i adolescets. Prev Med; 36: [9] Ribeiro J, Guerra A, Pito A, Oliveira J, Duarte J, Mota J. (2003). Overweight ad obesity i childre ad adolescets: relatioship with blood pressure, physical activity. A Hum Biol; 30:

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