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Eigil Fossum

Publications and source records attributed to Eigil Fossum.

14 recordsLinked to original sources

Blood viscosity: effects of mental stress and relations to autonomic nervous system function and insulin sensitivity.

We studied effects of mental stress on whole-blood viscosity (WBV) and blood pressure (BP), and relations between WBV and autonomic nervous system activity and insulin sensitivity. We measured WBV (rotational rheometer), plasma noradrenaline (NA), finger BP, heart rate variability (HRV) and baroreflex sensitivity (BRS; transfer technique) during hyperinsulinaemic glucose clamp and mental arithmetic stress test (MST) in 20 men with high ( > or =140/90 mmHg) and 21 men with normal (< or =115/75 mmHg) screening BP, and 10 women regardless of screening BP (all normotensive). WBV and NA increased during the MST, while HRV and BRS decreased. During the MST, WBV (all shear rates) and the response ((delta)WBV) (low shear) were higher in men with high compared to normal screening BP (p<0.05). In men, WBV correlated positively with NA and negatively with HRV, BRS and insulin sensitivity. The diastolic BP response ((delta)DBP) was independently explained by high-shear (delta)WBV (p<0.05) and (delta)NA (p<0.0001), and (delta)WBV independently by (delta)DBP (p<0.05). WBV is related to increased sympathetic activity, impaired vagal cardiac control and low insulin sensitivity in young adults. The haemorheological effect of mental stress is increased in young men with high screening BP and may be mediated by the acute increase in BP.

Adult↗

Long-term treatment with losartan versus atenolol improves insulin sensitivity in hypertension: ICARUS, a LIFE substudy.

OBJECTIVE: Hypertension and insulin resistance might be associated through peripheral vascular hypertrophy/rarefaction which compromises skeletal muscle blood flow and decreases glucose uptake, inducing insulin resistance. We hypothesized that treatment with losartan as compared to atenolol would improve insulin sensitivity through regression of peripheral vascular hypertrophy/rarefaction. METHODS: In 70 hypertensive patients with electrocardiographic left ventricular hypertrophy, we measured minimal forearm vascular resistance (MFVR) by plethysmography and insulin sensitivity (M/IG) by a 2-h isoglycemic hyperinsulinemic clamp at baseline and after 1, 2 and 3 years of blinded treatment with atenolol- or losartan-based regimens. RESULTS: Blood pressures were reduced similarly in the two treatment groups. After 3 years, MFVR was increased (3.7 versus 3.2 mmHg x min x 100, P < 0.05) and M/IG decreased (8.6 versus 12.1 l/kg x mmol x min, P < 0.05) in patients treated with atenolol, whereas MFVR and M/IG were unchanged (3.5 versus 3.5 mmHg x min x 100 and 12.6 versus 11.1 l/kg x mmol x min, both P = NS) in patients treated with losartan. As compared to atenolol, losartan treatment was associated with less increase in MFVR (4.3 versus 27%, P < 0.05) and less decrease in M/IG (24 versus -14%, P < 0.01). The relative change in M/IG was inversely associated with the relative change in MFVR (r = -0.16, P < 0.05) independently of the relative change in body mass index (r = -0.29, P < 0.001). CONCLUSIONS: As compared to atenolol, losartan treatment was associated with less peripheral vascular hypertrophy/rarefaction and higher insulin sensitivity. The relative change in MFVR and M/IG were inversely related, supporting the hypothesis that peripheral vascular changes in hypertension may induce insulin resistance. The ability of losartan to preserve insulin sensitivity may explain the lower incidence of new onset diabetes in patients treated with losartan in the LIFE study.

Aged↗

Opposite effects of losartan and atenolol on natriuretic peptides in patients with hypertension and left ventricular hypertrophy: a LIFE substudy.

BACKGROUND: Secretion of natriuretic peptides is related to cardiac wall stress and influenced by the renin-angiotensin system. Therefore, we investigated the influence of blood pressure (BP) reduction with losartan versus atenolol on N-terminal pro-atrial natriuretic peptide (Nt-proANP) and N-terminal pro-brain natriuretic peptide (Nt-proBNP). METHODS: In 183 patients with hypertension and electrocardiographic left ventricular (LV) hypertrophy, enrolled in the LIFE Study, we measured BP and serum Nt-proANP and Nt-proBNP by immunoassay after 2 weeks of placebo treatment and after 1, 2, 4, 6, 12, 24, 36 and 48 months of randomized treatment with losartan- or atenolol-based antihypertensive regimens. RESULTS: There was no significant difference in BP at any time point between the two treatment groups. In patients treated with losartan, median Nt-proANP decreased gradually throughout the study, reaching significance after 6 months of treatment (1125-1060 pmol/l, P < 0.001), and Nt-proBNP decreased within the first month (24.7-18.7 pmol/l, P < 0.01) and stayed reduced throughout the study. During losartan-based antihypertensive treatment, Nt-proANP and Nt-proBNP as a percentage of baseline values were correlated to reductions in systolic BP (r = 0.11, P < 0.01 and r = 0.10, P = 0.01) and diastolic BP (r = 0.17, P < 0.001 and r = 0.07, P = 0.09). In atenolol-treated patients, Nt-proANP (1100-1640 pmol/l, P < 0.001) and Nt-proBNP (20.0-37.7 pmol/l, P < 0.001) increased during the first month, and remained elevated throughout the study. During atenolol-based antihypertensive treatment, changes in Nt-proANP (r = -0.16, P < 0.001) and Nt-proBNP (r = -0.07, P = 0.08) were negatively related to change in heart rate. CONCLUSION: Nt-proANP and Nt-proBNP were reduced in parallel with BP in losartan-treated patients whereas they increased in parallel with decreased heart rate in atenolol-treated patients.

Aged↗

Adrenal medullary overactivity in lean, borderline hypertensive young men.

BACKGROUND: There may be a link among stress, adrenal medullary activation, and the development of hypertension. Obesity is characterized by sympathetic activation and predisposes to hypertension, but may be associated with low or normal adrenal medullary activity. We hypothesized that plasma epinephrine (E) levels and adrenal medullary responsiveness to mental stress are lower in overweight than in lean borderline hypertensive subjects. METHODS: We compared groups of lean (n = 62) and overweight (n = 29) borderline hypertensive young men as well as lean (n = 36) and overweight (n = 7) normotensive young men from the same population. Plasma catecholamines and heart rate (HR) were measured at rest during a hyperinsulinemic glucose clamp and during mental arithmetic-induced stress. RESULTS: Plasma norepinephrine (NE) and E, HR, and responses to stress were increased in borderline hypertensive subjects. Our results showed that NE was increased only in lean borderline hypertensive subjects at rest, but in overweight subjects as well during stress, with DeltaNE being similar in lean and overweight subjects. We found that E was higher in lean than in overweight borderline hypertensive subjects at rest and during stress (both P <.001), as were DeltaE and DeltaHR (both P <.05). Independent of BP status, body mass index was negatively related to E during stress (P <.01) and waist circumference negatively related to resting E (P <.001) and DeltaHR (P =.02). CONCLUSIONS: Sympathetic neural activity and responsiveness are increased in borderline hypertensive young men, but measures of overweight are independently related to lower plasma E and HR responses. We suggest that adrenal medullary activation in borderline hypertension mainly characterizes lean subjects.

Adolescent↗

High screening blood pressure is related to sympathetic nervous system activity and insulin resistance in healthy young men.

The cardiovascular metabolic syndrome is characterized by the presence of several cardiovascular risk factors, including blood pressure (BP) elevation. We aimed to study the relation between mental stress, plasma catecholamines, BP and BP responses to mental stress in healthy young Caucasian men selected from different levels of screening BP. We included 98 men with high and 22 men with normal screening BP. They were examined at baseline in the laboratory, during a hyperinsulinemic, isoglycemic glucose clamp and during mental stress. At baseline in the laboratory, the men with high screening BP were characterized by elevated BP (p < 0.005) and plasma catecholamines (p < 0.05), but unaltered serum lipid levels compared to men with normal screening BP. After 2 h rest the differences almost disappeared, but could be reproduced during a mental arithmetic stress test. The men with elevated screening BP had significantly higher fasting glucose (p = 0.01) and lower insulin sensitivity (p < 0.005). In a multiple regression model, norepinephrine during mental stress (R2 = 0.10, p < 0.05) was the main variable to retrospectively explain allocation to the normal or high screening BP group. In conclusion, young healthy men with elevated screening BP are characterized by increased sympathetic activity and insulin resistance. Norepinephrine during mental stress is the main variable to explain allocation to the normal or elevated screening BP group. We have shown that one single screening BP measurement predicts insulin resistance and elevated fasting glucose in this cohort.

Adolescent↗

Plasma catecholamines, blood pressure responses and perceived stress during mental arithmetic stress in young men.

We assessed plasma noradrenaline (NA) and adrenaline (A) at rest during a hyperinsulinaemic glucose clamp and responses to a mental arithmetic stress test (MST) in relation to blood pressure (BP) responses (Finapres) and distress in 20 men with high (> or =140/90 mmHg) and 21 men with normal (< or =115/75 mmHg) screening BP, 21-24 years of age. Perceived stress, effort and overall discomfort were scored 1-10. Catecholamines and BP increased in both groups, change in diastolic BP (DeltaDBP; 9.9 vs. 3.8 mmHg, p < 0.05) and DeltaDBP carryover (recovery period minus baseline) (7.2 vs. 2.2 mmHg, p < 0.01) being greater in men with high screening BP. Independently of BP status, change in systolic BP (DeltaSBP) and DeltaSBP carryover were related to A (both p < 0.001), and DeltaDBP and DeltaDBP carryover to DeltaNA (both p < 0.001). The subjective score sum correlated with maximal NA (rs = 0.40) and A (rs = 0.37) (both p < 0.05). Maximal NA was independently related to stress (p < 0.05) and the subjective score sum (p < 0.01). DeltaA% was greater in the high- (score > or =6) than in the low-stress category, independently of BP status (p < 0.05). High screening BP is associated with impaired BP recovery after mental stress. Plasma catecholamine responses are related to BP responses and carryover effects, and reflect perceived stress in young men.

Adult↗

Relations between insulin sensitivity, fitness and autonomic cardiac regulation in healthy, young men.

OBJECTIVES: We hypothesized that insulin sensitivity and vagal cardiac control are independently related in young men after adjustment for fitness and other confounding variables. DESIGN: Male volunteers aged 21-24 years with high (borderline hypertensive; n = 20) and low-normal (normotensive; n = 21) screening blood pressure (BP) were studied cross-sectionally. METHODS: Mean R-R interval (RR) and heart rate variability (HRV) were computed from 30-min ECGs, and baroreflex sensitivity (BRS) and latency (phase shift) from 15-min beat-to-beat finger blood pressure (BP) and heart rate recordings. Insulin-adjusted glucose disposal rate (GDR/I) was measured with a 90-min hyperinsulinaemic glucose clamp and fitness by peak oxygen uptake (VO2peak) during a treadmill test. RESULTS: HRV, baroreflex function, GDR/I, and VO2peak did not differ between the groups. GDR/I correlated positively with time and frequency domain HRV, including high-frequency power (HF) (r = 0.40, P = 0.01) and root-mean squared successive differences (RMSSD) (r = 0.43, P = 0.005), but not BRS or phase shift. GDR/I correlated with VO2peak (r = 0.70, P < 0.0001) and was explained (R = 0.56) by VO2peak (beta = 0.57, P < 0.0001) and RR (beta = 0.29, P = 0.03), independently of HRV and measures of obesity. Conversely, RR (beta = 0.55, P = 0.0004) and HRV, including HF (beta = 0.44, P = 0.006) and RMSSD (beta = 0.46, P = 0.004) were explained by GDR/I, independently of VO2peak. CONCLUSIONS: Insulin sensitivity and autonomic cardiac control are related independently of physical fitness in young men.

Adult↗

N-terminal pro-brain natriuretic peptide predicts cardiovascular events in patients with hypertension and left ventricular hypertrophy: a LIFE study.

BACKGROUND: N-terminal pro-brain natriuretic peptide (Nt-proBNP) and N-terminal pro-atrial natriuretic peptide (Nt-proANP) are strong cardiovascular risk markers in patients with chronic heart failure, as well as in the general population. We investigated whether high Nt-proBNP or Nt-proANP could also predict the composite endpoint (CEP) of cardiovascular death, non-fatal stroke or non-fatal myocardial infarction in patients with hypertension and left ventricular (LV) hypertrophy. METHODS: After 2 weeks of placebo treatment, clinical, laboratory and echocardiographic variables were assessed in 183 hypertensive participants in the LIFE echo substudy with electrocardiographic LV hypertrophy. Nt-proBNP and Nt-proANP were measured by immunoassay at baseline. The patients were followed for 60 +/- 5 months. RESULTS: Using Cox regression analysis, the 25 CEP were predicted by ln(Nt-proBNP) (hazard ratio 1.61 per 2.73-fold increase, P < 0.01) as well as ln(Nt-proANP) (hazard ratio 2.93, P < 0.05). Nt-proBNP above the median value of 21.8 pmol/ml was associated with higher incidence of CEP (19.6 versus 7.7%, P < 0.05). Nt-proBNP above the median value was associated with higher incidence of CEP in the 123 patients without history of diabetes or cardiovascular disease (14.8 versus 4.3%, P < 0.05), but the association was insignificant in the 60 patients with a history of diabetes or cardiovascular disease (26.3 versus 18.2%, NS). Nt-proANP showed the same tendency. CONCLUSION: Nt-proBNP, more than Nt-proANP, strongly predicts cardiovascular events in patients with hypertension and LV hypertrophy, especially in patients without diabetes or clinically overt cardiovascular disease.

Aged↗

[Aortic dissection--a differential diagnosis in patients with chest pain and ECG changes].

BACKGROUND: The effect of thrombolytic therapy in patients with myocardial infarction is well documented. In patients presenting with chest pain it may, however, be difficult to discriminate between myocardial infarction and aortic dissection only on the basis of clinical manifestations. Moreover, patients with type A dissection may have ECG changes caused by affection of the coronary flow. MATERIAL AND METHODS: We retrospectively investigated all patients admitted to our hospital with type A dissection of the aorta over the period 1999 to March 2001. RESULTS: Fourteen patients were identified. Only two patients had normal ECG, six had ST elevation. Two patients had received antithrombotic or thrombolytic therapy. INTERPRETATION: In patients with chest pain and ST elevation, aortic dissection must be considered as a differential diagnosis before thrombolytic therapy.

Adult↗

Serum uric acid and hemorheology in borderline hypertensives and in subjects with established hypertension and left ventricular hypertrophy.

Serum uric acid (SUA) but also hemorheological parameters such as hematocrit (Hct) and whole blood viscosity (WBV) are markers of cardiovascular risk. Increased blood cell volume is one of the known causes of hyperuricemia. We therefore aimed to investigate the relationship between SUA and hemorheology in untreated borderline hypertensive young men (n = 67) and in subjects with established hypertension and left ventricular hypertrophy (n = 40) examined when they had been without treatment for 2 weeks. We found positive correlations between SUA and Hct (r = 0.46, p < 0.0001), hemoglobin (Hgb) (r = 0.40, p = 0.001), mean blood pressure (BP) (r = 0.39, p = 0.001) and body weight (r = 0.26, p = 0.036) in the borderline hypertensive young men. No relation between SUA and glucose disposal rate (GDR) assessed with hyperinsulinemic isoglycemic glucose clamp appeared (r = -0.06, p = 0.633). Multiple regression analysis showed that 33% of the variation in SUA could be explained by BP and Hct. We also found positive correlations between SUA and Hgb (r = 0.40, p = 0.011) and body weight (r = 0.42, p = 0.006) and an inverse trend with GDR (r = -0.27, p = 0.087) in the subjects with established hypertension. Multiple regression showed that 32% of the variation in SUA was explained by Hgb and body weight. These data suggest that hemorheology may be involved in the uric acid metabolism in borderline as well as in established hypertensives. Hemorheology may possibly be a link between SUA and cardiovascular risk. There was no relation between SUA and insulin resistance in these hypertensive groups.

Adolescent↗

Lower plasma noradrenaline and blood viscosity on carvedilol vs atenolol in men with recent myocardial infarction.

The Carvedilol Acute Myocardial Infarction Study (CAMIS) investigates cardiac remodeling in patients (n = 250) randomized to carvedilol vs atenolol and treated for 12 months after acute myocardial infarction. In a sub-study, we compared sympathetic, hemorrheological and vascular effects in small but particularly well-matched groups of participants who had been on reasonably equipotent but unchanged doses of carvedilol (n = 10) or atenolol (n = 10) for at least 4 weeks. Blood pressures (p < 0.05), plasma adrenaline (p = 0.034), plasma vasopressin (p = 0.022) and whole blood viscosity at shear rate 0.5 cp (p = 0.050), 1.1 cp (p = 0.023), 5.8 cp (p = 0.049) and 201 cp (p = 0.060) taken in the laboratory at baseline before 2 h of using the hyperinsulinemic, isoglycemic glucose clamp were lower on carvedilol. Plasma noradrenaline was lower on carvedilol at baseline and throughout the clamp (p < 0.0005). Forearm vascular resistance as measured by plethysmography during the clamp tended to be lower on carvedilol (p = 0.074). No significant difference was found between the groups in glucose disposal rate measured by clamp, maximal forearm blood flow and minimal forearm vascular resistance after 10 min of ischemia, or in ambulatory blood pressure and heart rate taken a few days later. Thus, potential benefits of carvedilol vs atenolol were seen in these post-infarction patients in a laboratory setting. These findings suggest that the inhibitory effects on the sympathetic nervous system and related blood viscosity are stronger with carvedilol than with atenolol.

Adrenergic alpha-Antagonists↗