Long-term stable obesity increases risk of hypertension

• Published in: International Journal of Obesity Vol. 35; no. 8; pp. 1056 - 1062
• Main Authors: Matsuo, T, Sairenchi, T, Suzuki, K, Tanaka, K, Muto, T
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.08.2011; Nature Publishing Group
• Subjects: 692/499; 692/699/1702/393; 692/699/75/243; Adult; Analysis; Antihypertensives; Arterial hypertension. Arterial hypotension; Biological and medical sciences; Blood and lymphatic vessels; Blood pressure; Body mass; Body Mass Index; Body Weight; Cardiology. Vascular system; Cardiovascular disease; Cohort analysis; cohort studies; complications; confidence interval; Development and progression; Diagnosis; Epidemiology; etiology; Follow-Up Studies; Health Promotion and Disease Prevention; Humans; Hypertension; Hypertension - epidemiology; Hypertension - etiology; Hypertension - physiopathology; Internal Medicine; Japan; Japan - epidemiology; Male; Medical sciences; Medicine; Medicine & Public Health; men; Metabolic Diseases; Middle Aged; Miscellaneous; Obesity; Obesity - complications; Obesity - epidemiology; Obesity - physiopathology; Objectives; original-article; physiopathology; Preventive health; Proportional Hazards Models; Prospective Studies; Public Health; Public health. Hygiene; Public health. Hygiene-occupational medicine; Regression analysis; risk; Risk Assessment; Risk Factors; Stability; Time Factors; Weight control; Japan; blood pressure; time-dependent covariate; weight change; prospective cohort study; hypertension; body mass index; Hypertension; Obesity; Nutrition; Body weight; Nutrition disorder; Variations; Cardiovascular disease; Metabolic diseases; Risk; Corporal biometry; Increase; Long term; Prospective; Body mass index; Cohort study; Risk factor; Arterial pressure; Blood pressure; Hemodynamics; Nutritional status; Public health
• ISSN: 0307-0565; 1476-5497; 1476-5497
• DOI: 10.1038/ijo.2010.226

Objectives: Although some prospective cohort studies have shown that baseline BMI is positively associated with a future incident risk for hypertension, these studies do not account for weight changes during the observation period. Therefore, it is not evident whether future incident risk for hypertension in obese, non-hypertensive people increases when their weight remains stable. We examined the association between long-term weight stability and risk for developing hypertension. Methods: A total of 5201 Japanese male workers aged 30–59 years underwent health checkups in 2002 and were followed through 2006. To consider transitions in covariates during the follow-up period, we used a time-dependent covariate Cox proportional hazard model to compute the relative risks (RRs) of incident hypertension. Furthermore, as a complementary analysis, we restricted the data to individuals whose BMI remained unchanged (±5% of baseline BMI) during the follow-up and compared the RRs between BMI categories. Results: During the follow-up, there were 899 newly diagnosed cases of hypertension among the 5201 men (14 888 person-years). Mean change in BMI during the follow-up period of all subjects was 0.2±1.1 kg/m 2 (range: −6.6 to 6.3 kg/m 2 ). The multivariate RRs for hypertension increased as BMI increased when we applied the time-dependent covariate Cox proportional hazard model. The complementary analysis showed that the multivariate RR (confidence interval) within the ⩾27.0 kg/m 2 BMI category was 1.43 (1.16–1.77) times higher than the reference of 23.0–24.9 kg/m 2 , whereas the RR for the <21.0 kg/m 2 BMI category was 0.63 (0.51–0.79) times lower than the reference. Conclusions: A higher baseline BMI increases future incident risk for hypertension even when there has been no major weight increase. Weight management should be encouraged for obese, non-hypertensive people to prevent future hypertension.