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The effect of age on the relationship between body weight pulse rate and blood pressure
AJH–May 2003–VOL. 16, NO. 5, PART 2
Aims: To evaluate the influence of adiposity distribution (ADP) on ABPM, heart rate (HR), cardiac structure and urinary albumin excretion (UAE) in normotensive (OBNT) and hypertensive (OBHT) obese patients. Methods: 37 OBNT women, 19 with visceral ADP (V-OBNT) and 18 with peripheric ADP (P-OBNT) , 21 to 60 years, BMI 30,4 to 50 kg/m2 and 49 OBHT women , 37 V-OBHT and 12 P-OBHT, 26 to 65 years, BMI 30,1 to 40,8 kg/m2, were selected and submited to ABPM, echocardiography and UAE (post 4 week washout period) .Age, BMI and office BP was similar between obese subgroups. Results: V and P-OBNT presented similar ABPM levels. Nonetheless, both day and night HR were higher in V-OBNT: 90,1⫾8,3 vs 80,4⫾10,9, p⬍ 0,05 and 76⫾8,7 vs 70,4⫾7,5, p ⬍0,04. Septal thickness (ST), was also greater in V-OBNT: 9,4⫾1,3 vs 8,5⫾1,0mm, p⬍0,03 but UAE was not different:10,7(4,6/43,1) vs 3,2(1,8/29,7). Independent parameters (waist-W, waist/hip-W/H, age, BMI, day/night-SBP, day/night-DBP, glucose and insulin) put in a multiple regression, denoted an impact of W on ST (p⬍ 0,0008), posterior wall tickness (PW) (p⬍0,002) and of BMI and W/H on HR (p⬍ 0,04; p⬍ 0,008 respectively). Insulin predicted ST (p⬍0,002) and PW(p⬍0,003) when W and W/H were not in the model. In OBHT, visceral pattern predicted a less intense SBP dipping (SBPdp) (-9,5⫾ 5,0 vs–12,9⫾ 5,3 % observed in P-OBHT p⬍0,05) and a trend to higher night BP levels, but not HR levels. There was also a trend to greater cardiorenal injury degree in V-OBHT: left ventricular mass/ height2,754,9⫾14 vs 50,2⫾5,6 g/m2,7; E/A 0,95⫾0,34 vs 1,12⫾0,5; UAE 36,5(6,1/96,1)vs15(7,6/66,6) mcg/min. For the whole OBHT group SBPdipping correlated with LVM/h 2,7 (r2-0,33, p⬍0,02), E/A (r20,27, p⬍ 0,05) and UAE (r2-0,33, p⬍0,03). In multiple regression, night SPB was the best predictor variable for cardiorenal changes in OBHT. Conclusions: Visceral obesity in NT predicts changes in septum thickness and in heart rate, while in HT, V-obesity is a predictor for the lack of an adequate SBP dipping, which may play role in cardiorenal injury. Key Words: obesity, visceral fat distribution, target organ damage
P-521 THE EFFECT OF AGE ON THE RELATIONSHIP BETWEEN BODY WEIGHT PULSE RATE AND BLOOD PRESSURE David S Martins, Naureen Tareen, Deyu Pan, Keith C Norris. Internal Medicine, Charles R. Drew University, Los Angeles, CA; Internal Medicine, University of California, Los Angeles, CA. Obesity is associated with high insulin and leptin levels. Studies also suggest that high levels of insulin and leptin increase sympathetic nervous system (SNS) activity and engender increase chronotropy, vasoconstriction and antinatriuresis that may contribute to the pathogenesis of obesity related hypertension. Sympathetic modulation of cardiovascular responses requires good baroreceptor sensitivity and optimal vascular compliance. Age-related vascular changes associated with diminished baroreceptor sensitivity and vascular compliance may attenuate the hypertensive effect of obesity in the elderly. The purpose of this study is to assess the relationship between body mass index (BMI), blood pressure (BP) and pulse rate (PR) among participants younger than 65 years and those 65 years older using data from the third National Health And Nutrition Examination Survey. We examined data from 13,761 noninstitutionalized adults 18 years and older. Results showed that BP and PR increases with increasing BMI deciles. The rise in PR and BP with BMI is higher among participants younger than 65 years than among those 65 years and older. We concluded that age-related vascular changes in participants 65 years and older mitigate the cardiovascular responses to increased SNS overactivity associated with obesity. [Supported by awards numbers G12RR-03026-11, U54RR14616 and P20-RR11145-20 from the RCMI Program, NCRR, NIH] Key Words: Obesity, Body mass index, Blood pressure
POSTERS: Obesity, Insulin Resistance, Diabetes
227A
P-522 RELATIONSHIP BETWEEN INSULIN RESISTANCE AND THE RENIN-ANGIOTENSIN SYSTEM – ANALYSIS IN PATIENTS WITH ESSENTIAL AND RENOVASCULAR HYPERTENSION Tetsutaro Matayoshi, Kei Kamide, Shin Takiuchi, Masayoshi Yoshii, Yuhei Kawano. Division of Hypertension and Nephrology, National Cardiovascular Center, Suita, Osaka, Japan. Insulin resistance is frequently observed in patient with essential hypertension (EHT), and the renin-angiotensin system (RAS) has been suggested to be related to the development of insulin resistance. Renovascular hypertension (RVHT) has a special feature represented by highly activated systemic RAS. The aim of the present study was to investigate the role of circulating RAS in the mechanisms of insulin resistance in patients with RVHT and EHT. Subjects consisted of age- and sex- matched 13 RVHT and 89 EHT patients. Patients with overt diabetes (HbA1c ⱖ7.0% and/or taking oral hypoglycemic agents, insulin therapy) and secondary hypertension except RVHT were excluded. Plasma renin activity (PRA), fasting plasma glucose (FPG) and immuno-reactive insulin (IRI) were measured . Part of subjects had oral glucose tolerance test (OGTT) including glucose and IRI at 0, 30, 60, 120 minutes. HOMA-R index was calculated by (FPG x IRI)/405 as an index of insulin resistance. Sum of IRI during OGTT (⌺IRI )or IRI at 120 minutes (120 IRI) were used for indices of hyperinsulinemia. Characteristics of subjects including body mass index (BMI), blood pressure level and prevalence of hypertension in relatives were similar in RVHT and EHT groups. PRA was significantly higher in RVHT than EHT (RVHT:8.48⫾2.65 vs. EHT: 2.15⫾0.36 ng/ml/hr, p⬍0.0001,adjusted for BMI). There were no significant differences in HOMA-R, ⌺IRI and 120IRI between two groups. Significant correlations between PRA and all indicators of insulin sensitivity were observed in EHT (PRA vs. HOMA-R, ⌺IRI and 120IRI, R’b2⫽0.095, 0.079, 0.154, p⫽0.035, 0.047, 0.026, respectively), but not in RVHT. In order to further investigate the role of genetic background in the mechanism of insulin resistance, comparisons of insulin sensitivity indicators were performed in positive and negative groups of hypertension family history. In consequence, 120IRI was significantly higher only in male group with hypertension family history than without family history (p⫽0.043) though HOMA-R and ⌺IRI did not show any differences in all groups. In conclusion, the RAS activation in renal artery stenosis might not be associated with development of insulin resistance. However, the systemic RAS may modulate insulin sensitivity in essential hypertensives, who are supposed to be influenced by genetic backgrounds. Key Words: renin-angiotensin system, insulin sensitivity, renovascular hypertension
P-523 ARE CALCIUM ANTAGONISTS BENEFICIAL IN THE DIABETIC HYPERTENSIVE PATIENT? Ehud Grossman, Franz H. Messerli. The Chaim Sheba Medical Center, Tel-Hashomer, Israel; Ochsner Clinic Foundation, New Orleans, LA. We analyzed the available data to assess the benefits of calcium antagonists in hypertensive patients with diabetes mellitus. A MEDLINE search of English-language articles published until January 2002 was undertaken using the terms diabetes mellitus, hypertension or blood pressure, and therapy. Pertinent articles cited in the identified papers were also reviewed. Included were only prospective randomized studies of more than 12 months’ duration that evaluated the effect of drug treatment on morbidity and mortality in diabetic hypertensive patients. We estimated the effect of treatment with calcium antagonists on morbidity and mortality in comparison to placebo, conventional therapy, and therapy that blocks the renin angiotensin system.
Aims: To evaluate the influence of adiposity distribution (ADP) on ABPM, heart rate (HR), cardiac structure and urinary albumin excretion (UAE) in normotensive (OBNT) and hypertensive (OBHT) obese patients. Methods: 37 OBNT women, 19 with visceral ADP (V-OBNT) and 18 with peripheric ADP (P-OBNT) , 21 to 60 years, BMI 30,4 to 50 kg/m2 and 49 OBHT women , 37 V-OBHT and 12 P-OBHT, 26 to 65 years, BMI 30,1 to 40,8 kg/m2, were selected and submited to ABPM, echocardiography and UAE (post 4 week washout period) .Age, BMI and office BP was similar between obese subgroups. Results: V and P-OBNT presented similar ABPM levels. Nonetheless, both day and night HR were higher in V-OBNT: 90,1⫾8,3 vs 80,4⫾10,9, p⬍ 0,05 and 76⫾8,7 vs 70,4⫾7,5, p ⬍0,04. Septal thickness (ST), was also greater in V-OBNT: 9,4⫾1,3 vs 8,5⫾1,0mm, p⬍0,03 but UAE was not different:10,7(4,6/43,1) vs 3,2(1,8/29,7). Independent parameters (waist-W, waist/hip-W/H, age, BMI, day/night-SBP, day/night-DBP, glucose and insulin) put in a multiple regression, denoted an impact of W on ST (p⬍ 0,0008), posterior wall tickness (PW) (p⬍0,002) and of BMI and W/H on HR (p⬍ 0,04; p⬍ 0,008 respectively). Insulin predicted ST (p⬍0,002) and PW(p⬍0,003) when W and W/H were not in the model. In OBHT, visceral pattern predicted a less intense SBP dipping (SBPdp) (-9,5⫾ 5,0 vs–12,9⫾ 5,3 % observed in P-OBHT p⬍0,05) and a trend to higher night BP levels, but not HR levels. There was also a trend to greater cardiorenal injury degree in V-OBHT: left ventricular mass/ height2,754,9⫾14 vs 50,2⫾5,6 g/m2,7; E/A 0,95⫾0,34 vs 1,12⫾0,5; UAE 36,5(6,1/96,1)vs15(7,6/66,6) mcg/min. For the whole OBHT group SBPdipping correlated with LVM/h 2,7 (r2-0,33, p⬍0,02), E/A (r20,27, p⬍ 0,05) and UAE (r2-0,33, p⬍0,03). In multiple regression, night SPB was the best predictor variable for cardiorenal changes in OBHT. Conclusions: Visceral obesity in NT predicts changes in septum thickness and in heart rate, while in HT, V-obesity is a predictor for the lack of an adequate SBP dipping, which may play role in cardiorenal injury. Key Words: obesity, visceral fat distribution, target organ damage
P-521 THE EFFECT OF AGE ON THE RELATIONSHIP BETWEEN BODY WEIGHT PULSE RATE AND BLOOD PRESSURE David S Martins, Naureen Tareen, Deyu Pan, Keith C Norris. Internal Medicine, Charles R. Drew University, Los Angeles, CA; Internal Medicine, University of California, Los Angeles, CA. Obesity is associated with high insulin and leptin levels. Studies also suggest that high levels of insulin and leptin increase sympathetic nervous system (SNS) activity and engender increase chronotropy, vasoconstriction and antinatriuresis that may contribute to the pathogenesis of obesity related hypertension. Sympathetic modulation of cardiovascular responses requires good baroreceptor sensitivity and optimal vascular compliance. Age-related vascular changes associated with diminished baroreceptor sensitivity and vascular compliance may attenuate the hypertensive effect of obesity in the elderly. The purpose of this study is to assess the relationship between body mass index (BMI), blood pressure (BP) and pulse rate (PR) among participants younger than 65 years and those 65 years older using data from the third National Health And Nutrition Examination Survey. We examined data from 13,761 noninstitutionalized adults 18 years and older. Results showed that BP and PR increases with increasing BMI deciles. The rise in PR and BP with BMI is higher among participants younger than 65 years than among those 65 years and older. We concluded that age-related vascular changes in participants 65 years and older mitigate the cardiovascular responses to increased SNS overactivity associated with obesity. [Supported by awards numbers G12RR-03026-11, U54RR14616 and P20-RR11145-20 from the RCMI Program, NCRR, NIH] Key Words: Obesity, Body mass index, Blood pressure
POSTERS: Obesity, Insulin Resistance, Diabetes
227A
P-522 RELATIONSHIP BETWEEN INSULIN RESISTANCE AND THE RENIN-ANGIOTENSIN SYSTEM – ANALYSIS IN PATIENTS WITH ESSENTIAL AND RENOVASCULAR HYPERTENSION Tetsutaro Matayoshi, Kei Kamide, Shin Takiuchi, Masayoshi Yoshii, Yuhei Kawano. Division of Hypertension and Nephrology, National Cardiovascular Center, Suita, Osaka, Japan. Insulin resistance is frequently observed in patient with essential hypertension (EHT), and the renin-angiotensin system (RAS) has been suggested to be related to the development of insulin resistance. Renovascular hypertension (RVHT) has a special feature represented by highly activated systemic RAS. The aim of the present study was to investigate the role of circulating RAS in the mechanisms of insulin resistance in patients with RVHT and EHT. Subjects consisted of age- and sex- matched 13 RVHT and 89 EHT patients. Patients with overt diabetes (HbA1c ⱖ7.0% and/or taking oral hypoglycemic agents, insulin therapy) and secondary hypertension except RVHT were excluded. Plasma renin activity (PRA), fasting plasma glucose (FPG) and immuno-reactive insulin (IRI) were measured . Part of subjects had oral glucose tolerance test (OGTT) including glucose and IRI at 0, 30, 60, 120 minutes. HOMA-R index was calculated by (FPG x IRI)/405 as an index of insulin resistance. Sum of IRI during OGTT (⌺IRI )or IRI at 120 minutes (120 IRI) were used for indices of hyperinsulinemia. Characteristics of subjects including body mass index (BMI), blood pressure level and prevalence of hypertension in relatives were similar in RVHT and EHT groups. PRA was significantly higher in RVHT than EHT (RVHT:8.48⫾2.65 vs. EHT: 2.15⫾0.36 ng/ml/hr, p⬍0.0001,adjusted for BMI). There were no significant differences in HOMA-R, ⌺IRI and 120IRI between two groups. Significant correlations between PRA and all indicators of insulin sensitivity were observed in EHT (PRA vs. HOMA-R, ⌺IRI and 120IRI, R’b2⫽0.095, 0.079, 0.154, p⫽0.035, 0.047, 0.026, respectively), but not in RVHT. In order to further investigate the role of genetic background in the mechanism of insulin resistance, comparisons of insulin sensitivity indicators were performed in positive and negative groups of hypertension family history. In consequence, 120IRI was significantly higher only in male group with hypertension family history than without family history (p⫽0.043) though HOMA-R and ⌺IRI did not show any differences in all groups. In conclusion, the RAS activation in renal artery stenosis might not be associated with development of insulin resistance. However, the systemic RAS may modulate insulin sensitivity in essential hypertensives, who are supposed to be influenced by genetic backgrounds. Key Words: renin-angiotensin system, insulin sensitivity, renovascular hypertension
P-523 ARE CALCIUM ANTAGONISTS BENEFICIAL IN THE DIABETIC HYPERTENSIVE PATIENT? Ehud Grossman, Franz H. Messerli. The Chaim Sheba Medical Center, Tel-Hashomer, Israel; Ochsner Clinic Foundation, New Orleans, LA. We analyzed the available data to assess the benefits of calcium antagonists in hypertensive patients with diabetes mellitus. A MEDLINE search of English-language articles published until January 2002 was undertaken using the terms diabetes mellitus, hypertension or blood pressure, and therapy. Pertinent articles cited in the identified papers were also reviewed. Included were only prospective randomized studies of more than 12 months’ duration that evaluated the effect of drug treatment on morbidity and mortality in diabetic hypertensive patients. We estimated the effect of treatment with calcium antagonists on morbidity and mortality in comparison to placebo, conventional therapy, and therapy that blocks the renin angiotensin system.