214A
POSTERS: Nutrition and Electrolytes
P-568
LIFE-THREATENING HYPERKALEMIA: AN
EVOLVING PROBLEM AFTER THE RALES STUDY
Jesus Arteaga, Beatriz Espejo, Maria Sorbet. Nephrology, Hospital de
Navarra, Pamplona, Spain.
Spironolactone, an antagonist of aldosterone, is currently used in the
treatment of severe congestive heart failure, frequently in association
with angiotensin converting enzyme inhibitors(ACE) and/or AT1- receptor blockers, Betablockers and diuretics.
After publication of RALES study, it is well known that spironolactone reduce disease and death in patients with severe congestive heart
failure.However routine clinical practice does no permit such close
follow up as a well conducted trial does and hyperkalemia is going to
become more of an issue.We defined life-threatening hyperkalemia as
serum potassium ⬎6,5 mmol/l with serious clinical manifestations (neurologic or cardiac).
The purpose of this study was to analyze our experience during the last
12 months.During this time we have treated 8 patients (5M,3F),
aged(68-81 years) with life-threatening hyperkalemia requiring acute
dialysis. On admission serum potassium was between 6,8-9,1 mmol/L.
Serum creatinine (3,1-4,9 mg/dl) significantly higher than baseline values
(serum creatinine 1,8-2,7 mg/dl). 6 patients were diabetics. Combined
therapy with ACEI or ARB was present in 100%. Betablockers in 50%.
Nonsteroidal antiinflammatory drugs in 25%. The daily dose of spironolactone was between 25-200 mg.
Results.- 6 patients needed urgent dialysis. In 3 patients it was necessary more than one hemodialysis session . Two patients didn’t accept
hemodialysis treatment and were treated with conservative measures. 5
patients needed temporal cardiac pacemakers and 3 patients were treated
with mechanical ventilation. All patients suffered an acute worsening of
renal function that was followed by a progressive improvement..No
patient died.
Conclusions: We recommend that particular caution be taken in
elderly, diabetics and chronic renal patients with congestive heart failure.
These patients are at higher risk to suffer severe hyperkalemia when are
concomitantly treated with more than one hyperkalemic drug, that multiply inhibit the renin-angiotensin system. Potassium supplementation
should be discontinued. Doses in concomitant diuretic regimens may
need adjustment and continuous laboratory monitoring remains inevitable.
Key Words: Dialysis, Hyperkalemia, Spironolactone
P-569
ANTIOXIDANT VITAMINS AND ENDOTHELIAL
DYSFUNCTION IN THE DERMAL
MICROCIRCULATION
Rosa Fabregate, Arturo Ugalde, David Coca, Manuela Diez,
Olivia Sanchez, Maria Calbacho, Martin Fabregate, Jose Saban-Ruiz.
Endothelial Pathology Unit, Ramon y Cajal Hospital, Madrid, Spain.
Introduction: Oxidative stress is involved in the pathogenesis of endothelial dysfunction and atherosclerosis. In small clinical studies it was
found that both vitamins C and E may improve endothelial function in
contrast to the negative results of almost all large randomized trials. Sato
and co-workers (Clin Nephrol 2003 Jul; 60(1): 28-34) concluded that
supplementation with vitamin C and vitamin E may be of clinical benefit
in improving the cutaneous microcirculation by reducing oxidative stress.
Aims: 1.To determine the prevalence of abnormal cutaneous endothelium-dependent vasodilation. 2-To determine its correlation with antioxidant vitamins levels.
Material and Methods: N⫽80 patients, aged 31-81 years (61,72⫹1,35 ), 49,3% males, 55 hypertensives. Anthropometric parameters: BMI
0895-7061/05/$30.00
AJH–May 2005–VOL. 18, NO. 5, PART 2
(kg/m2) and waist (centimeters). Vitamins C (mg/dl), E (ug/dl), A
(ug/dl): HPLC. Endothelium (ED) and non endothelium-dependent
(NED) vasodilation: exploration of cutaneous microcirculatory responses
at the forearm with laser Doppler (DRT4, MOOR Instruments). The skin
blood flow response to transient occlusion of the circulation at the
forearm (reactive hyperemia, RH) was measured using a laser Doppler
imaging system. Peak-Flow associated to Reactive hyperemia (PFRH)
respect to baseline was considered normal ⬎67%, following our own
criteria in control subjects, and abnormal ⬍67%. Statistical analysis:
t-Student, chi-square and Mann-Whitney U tests; One-way ANOVA and
Linear Regression.
Results: 1-The prevalence of abnormal endothelium-dependent vasodilation was N⫽21 (16.8%). 2-There was statistical correlation with age
(p⫽0,047), but not with sex nor anthropometric parameters. The nitroprusside response was normal in all subjects. 3-Antioxidant vitamins: vitamin A
(p⫽0,047), vitamin E (p⫽0,033), and vitamin C (p⫽0,09, NS).
Conclusions: 1-The prevalence of endothelial dysfunction in the dermal microcirculation was of 21%. 2-The significant association with
antioxidant vitamins levels demonstrates that: a) oxidative stress is related to endothelial dysfunction and, most importantly b) perhaps a
healthy diet could revert both phenomena. 3-The current evidence does
not support the indiscriminate use of vitamins A, C, or E or beta-carotene
to prevent or reduce cardiovascular disease. However, there could be a
benefit in specific cases.
Key Words: Antioxidant Vitamins, Dermal Microcirculation, Endothelial
Dysfunction
P-570
IMPACT OF MODERATE ALCOHOL CONSUMPTION
ON ARTERIAL BLOOD PRESSURE
Rosa Fabregate, Judit Marquez, Olivia Sanchez, Enrique Bernal,
Martin Fabregate, Arturo Ugalde, David Coca,
Elena Sanchez-Largo, Jose Saban-Ruiz. Endothelial Pathology Unit,
Ramon y Cajal Hospital, Madrid, Madrid, Spain.
Introduction: In recent years, strong epidemiological evidence has associated light to moderate alcohol consumption with significant cardiovascular benefit, pointing out its influence on the levels of HDL.
However, up to date, very few studies have correlated alcohol consumption with 24-hour ambulatory blood pressure monitoring (ABPM).
Objectives: 1. To classify a population of high cardiovascular risk
according to the degree of alcohol consumption. 2. To correlate this
consumption with the levels of blood pressure (BP). 3. To study its
influence on oxidative stress.
Methods: Study population: N⫽200 patients of which we excluded 3
due to excessive alcohol consumption and 66 due to sporadic consumption. The remaining N⫽131 were classified in two groups:
Group A (daily consumption): n⫽31, 58⫹-11 years old, 24 males.
Group B (no consumption): n⫽100, 60⫹-13 years old, 27 males.
Anthropometric parameters: BMI (kg/m2), waist circumference (cm).
Biochemical parameters: Glycaemia, Triglycerides, Cholesterol, LDLc
(HITACHI), Insulinaemia (uU/mL)-Immunometric assay. Immulite.
DPC, Insulin resistance (HOMA).
Oxidative stress: oxidized-LDL (LDLox) (U/L): MERCODIA ELISA.
ABPM: Spacelabs 90207: Average 24h systolic BP (aSBP), diastolic
BP (aDBP), and BP mean (BPM: SBP-DBP ⫹ DBP/3); pulse pressure
and hemodynamic load (HL) ⫽ Heart Rate x BPM/100.
Statistical analysis: t-Student and Chi-square.
Results: 1. There were no significant statistical differences between
the two groups in terms of BMI (A:27.33⫹-0.74 vs B:27.96⫹-0.46),
waist circumference (A:297.6⫹-17.6 vs B:333.82⫹-9.44) and insulin
resistance (2.67⫹-0.29 vs 2.73⫹-0.21). 2. Patients in group A have
higher DBP levels (77.48⫹-1.85 vs 70.26⫹-1.06;p ⬍0.05), BPM
© 2005 by the American Journal of Hypertension, Ltd.
Published by Elsevier Inc.
AJH–May 2005–VOL. 18, NO. 5, PART 2
(95.34⫹-1.84 vs 89.94⫹-1.12;p ⬍0.05) and hemodynamic load
(73.25⫹-2.77 vs 66.12⫹-1.48;p ⬍0.05) than patients in group B. 3. Male
drinkers were found to have a significantly greater increase in SBP levels
(129.88⫹-2.38 vs 121.78⫹-2.47;p ⬍0.05) and pulse pressure (52.3⫹2.24 vs 46.52⫹-1.63;p ⬍0.05) than male non drinkers. 4. With similar
levels of glycaemia, total cholesterol, triglycerides, HDL and LDLc in
both groups, patients in group A have higher LDLox levels (111.57⫹10.6 vs 92.85⫹-4;p ⬍0.05). Male drinkers showed higher HDL levels
(58.18⫹-5.9 vs 47.84⫹-2.35;p ⬍0.05) then male non-drinkers.
Key Words: Alcohol, Arterial Blood Pressure, Oxidative Stress
P-571
PLASMA MAGNESIUM DEFCIENCY IS CORRELATED
TO PULSE PRESSURE VALUES IN ESSENTIAL
HYPERTENSION - INFLUENCE OF A METABOLIC
SYNDROME
Klaus Kisters, Oleg Hoffmann, Bernhard Gremmler, Martin Hausberg.
Department of Internal Medicine I, St. Anna Hospital, Herne,
Germany; Department of Cardiology, Marienhospital, Bottrop,
Germany; Department of Internal Medicine D, University of Muenster
Hospitals and Clinics, Muenster, Germany.
The height of pulse pressure (difference between systolic and diastolic
blood pressure values) is known to be a risk factor for cardiovascular
morbidity and mortality. In this context, it was of interest to study plasma
magnesium concentrations in essential hypertensives with pulse pressure ⬎ 60 mmHg and ⬍ 50 mmHg (twenty patients in each group). Our
results show that in the group with a high pulse pressure plasma magnesium concentrations were measured 0.76 ⫾ 0.05 mmol/l versus 0.88 ⫾
0.09 mmol/l in essential hypertensives with a pulse pressure ⬍ 50 mmHg
(p ⬍ 0.05, r ⫽ -0,73).
In addition, we could show no further magnesium deficiency in a
subgroup of patients with metabolic syndrome with high and low pulse
pressure as compared to non metabolic syndrome patients.
In conclusion the presented data show that in patients with elevated
pulse pressure values a magnesium deficiency may occure. The magnesium deficiency significantly correlates with the height of pulse pressure.
The results a similar to previous investigations in essential hypertensives.
As a benefit of a magnesium supplementation has been well documented
in the treatment of primary hypertension, further studies are necessary to
demonstrate a positive effect of a magnesium therapy in reducing pulse
pressure values.
Key Words: Magnesium, Metabolic Syndrome, Pulse Pressure
P-572
SODIUM INTAKE IN ELDERLY HYPERTENSIVES
AND OUTPATIENT COMPLIANCE WITH LOW
SODIUM DIET
George A Mansoor, Chaula Vora, William B White. Hypertension and
Clinical PHarmacology, Jim and Pat Calhoun Cardiology Center,
Farmington, CT.
It is well recognized that reductions in sodium intake lower blood
pressure in hypertensive patients. However, outpatient adherence to
current recommended levels of sodium intake (100meq/d)* and to very
low sodium diets is not well studied. We therefore examined ambient
sodium intake and short-term compliance with a 70 meq/day sodium diet
in elderly (⬎ 60 years) hypertensives participating in a study of sodium
intake and endothelial function. The key intervention was a nutritionist
who spent approximately one hour counseling patients on how to maintain a low sodium intake of 50-60 meq daily and followup with our study
nurse. There were 16 men and 13 women participating in the study with
a mean age of 61 ⫾ 6 yrs, BMI 28.3 kg/m2, and waist to hip ratio of
0.91⫾ 0.10. Renal function was normal in the population. The baseline
sodium excretion was 144 ⫾ 77 meq/day with 72% demonstrating
POSTERS: Nutrition and Electrolytes
215A
values ⬎ 100 meq/d. After one week on the prescribed low sodium diet,
urinary sodium declined to 67 ⫾ 36 meq/day (p⬍.001) with 13/29 (45%)
achieving ⱕ 60 meq/day. The average decline in men was higher than in
women (-102 ⫾ 79 vs - 45 ⫾ 64 meq/d, p⫽ 0.04), but baseline sodium
excretion was higher in men than women (180 ⫾ 82 vs 102 ⫾ 46
meq/day, p⫽ 0.005). Lower serum insulin and creatinine were seen in the
group that achieved the prescribed diet associated with lowered urinary
excretion of sodium.
Daily sodium intake in elderly hypertensive subjects is significantly
above recommended levels. After appropriate counseling and prescription of a 60-70meq/d sodium diet, 45% were able to reach the
prescribed goal within one week. Patients with higher insulin levels
and creatinine were less likely to achieve dietary sodium goals in one
week. It is likely that a period greater than 7 days is needed for urinary
to dietary sodium equilibration to occur in some subsets of elderly
hypertensives.
Characteristics of achievers and non-achievers of goal sodium
Parameters
Goal Na
achieved
(N ⴝ 13)
Goal Na
not achieved
(N ⴝ 16)
P-value
Age, years
Insulin, Iu/ml
Creatinine, mg/dl
Glucose, mg/dl
BMI, kg/m2
69 ⫾ 3
6.8 ⫾ 2
0.82 ⫾ 0.09
97 ⫾ 8
26.9 ⫾ 3.0
69 ⫾ 7
10.8 ⫾ 7
1.05 ⫾ 0.18
102 ⫾ 13
29.3 ⫾ 4.6
.13
.003
.03
.21
.27
All patients off antihypertensive drug therapy for 2 weeks
*Circulation 2000:102:2284-2299.
Key Words: Sodium, Elderly, Outpatient
P-573
MODERATE SALT RESTRICTION EFFECTIVELY
LOWERS BLOOD PRESSURE AND DEGREE OF SALT
SENSITIVITY IS PREDICTED BY PLASMA RENIN IN
SWEDISH SUBJECTS WITH NORMAL AND
SLIGHTLY ELEVATED BLOOD PRESSURE
Olle Melander, Fredrik von Wowern, Philippe Burri,
Gunilla Willsteen, Lennart U Hulthén. Department of Endocrinology,
Lund University, Malmö, Sweden.
The aim of this study was to test the effect of moderate dietary salt
restriction on blood pressure and whether plasma renin would predict
degree of salt sensitivity.
Plasma renin concentration (P-renin) was measured in the upright
position in 36 Swedish healthy subjects with normal or slightly elevated
blood pressure when being on their habitual diet. The mean age was
53⫾10 years, 44% were male and systolic and diastolic blood pressure
was 134⫾12 / 79⫾8 mmHg. During 8 weeks the subjects received all
meals and drinks from our metabolic ward with a total daily NaCl content
of 50 mmol. In addition, NaCl capslules (100 mmol/day) and corresponding placebo capsules were administered for 4 weeks each in random order
(cross-over design). Office blood pressure (OBP), ambulatory blood
pressure (ABP) and 24h urinary sodium excretion (tUNa) was measured
at baseline and after the 4 weeks of high- (150 mmol/day) and low- (50
mmol/day) salt intake. Salt sensitivity was defined as the difference
between 24-h ABP after the high- and low-salt periods.
The tUNa after the low- and high-salt periods were 50⫾17 and
140⫾39 mmol (P⬍0.0001) indicating good complience. The basline
tUNa (167⫾67 mmol) was significantly higher than tUNa after the
high-salt period (P⫽0.04), indicating that the habitual diet contained
more salt than the “high-salt” intake. Relative salt restriction (50 vs 150
mmol/day) induced highly significant reductions in blood pressure (mean
reduction, 95% CI) for systolic (6.7, 3.7-9.7 mmHg) and diastolic (4.5,
2.5-6.5 mmHg) OBP, for systolic and diastolic 24-h ABP (5.6, 3.1-8.1
and 2.5, 0.7-4.3 mmHg), daytime ABP (5.2, 2.5-7.9 and 2.2, 0.2-4.2