Study On The Relationship Between Hypertension Family History And BMI?24,Central Obesity And The Risk Of Hypertension

Research background:Hypertension brought heavy financial burden to China,while the prevalence of hypertension in China has been high all the time.Therefore,it is essential to explore risk factors of hypertension in order to prevent it by taking effective measures.Most studies on hypertension risk factors were univariate studies,and there were few reports on the interaction among its risk factors.Research objective:To explore the relation among hypertension family history,body mass index(BMI)?24 kg/m2,central obesity(indicated by waist circumference)and hypertension,and whether hypertension family history and BMI?24 kg/m2,central obesity had interaction effects on the prevalence of hypertensionMaterials and methods:Using stratified and sampling method,subjects were recruited in original seven districts and live cities in Qingdao.2402 hypertension patients were recruited into the case group.and 2710 subjects with normal blood pressure enrolled the control group.Univariate and multivariate unconditional logistic regression models were used to analyse the relationship among hypertension family history and BMI?24 kg/m2,central obesity and hypertension.The interaction effects among hypertension family history and BMI?24 kg/m2,central obesity and hypertension were analysed by additive models.Main results:1.Overall characteristic of subjectsThe average age of 5112 subjects was(52.3±10.8)years old.The average BMI of men was(24.6 ± 3.5)kg/m2,and the average BMI of women was(25.3±3.7)kg/m2.The average waist circumference in men was(85.1+10.7)cm,and the average waist circumference in women was(82.9±10.3)cm.BMI of 68.6%cases in the case group and 49.1%individuals in the control group was higher than 24kg/m2.69.0%cases were central obese in the case group,and 47.5%subjects were central obese in the control group.21.7%cases in the case group and 18.3%subjects in the control group had hypertension family history.2.Interaction effect between hypertension family history and BMI?24kg/m2Compared to those subjects without hypertension family history and BMI<24kg/m2.OR(A)of subjects with hypertension family history but BMI<24 kg/m2 was 1.18.and OR(B)of subjects without hypertension family history but BMI<24 kg/m2 was 2.25.and OR(AB)of subjects with both hypertension family history and BMI?24 kg/m2 was 2.60.After adjusting for potential confounders.OR(A).OR(B)and OR(AB)was 1.65.2.61 and 3.73,respectively.Synergistic index(S)was 1.12 when both hypertension family history and BMI?24kg/m2 existed,and attributable interaction[I(AB)]was 0.17.and attributable interaction percentage(AP%)was 6.5%.and pure attributable interaction percentage[AP*(AB)%]was 10.6%.After adjusting for confounding factors.S.I(AB),AP%and AP*(AB)%was 1.65.0.47.12.6%and 17.2%.respectively.3.Interaction effect between hypertension family history and central obesity on the prevalence of hypertensionCompared to those subjects without hypertension family history and central obesity.OR(A)of subjects with hypertension family history but without central obesity was 1.13.and OR(B)of subjects without hypertension family history but with central obesity was 2.42.and OR(AB)of subjects with both hypertension family history and central obesity was 2.90.After adjusting for age.gender.education.smoking.drinking.diabetes mellitus,hyperlipidemia.monthly income and so on.OR(A).OR(B)and OR(AB)was 1.61.2.50 and 3.75.respectively.Hypertension family history and central obesity had a positive interaction effect on the prevalence of hypertension.Synergistic index(S)was 1.23 when both hypertension family history and central obesity existed,and attributable interaction[I(AB)]was 0.35,and attributable interaction percentage(AP%)was 12.1%,and pure attributable interaction percentage[AP*(AB)%]was 18.4%.After adjusting for confounding factors,S,I(AB),AP%and AP*(AB)%was 1.65,0.64,12.6%and 17.2%.respectively.Conclusions:Hypertension family history,BMI?24kg/m2 and central obesity were all risk factors of hypertension.BMI?24kg/m2 and hypertension family history,central obesity and hypertension family history both had positive interaction effects on the prevalence of hypertension...