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H Lithell

Publications and source records attributed to H Lithell.

At least 55 records · Page 3Linked to original sources

Cerivastatin gender effect: sub-analyses of results from a multinational, randomised, double-blind study. Cerivastatin Study Group.

We previously reported the results of a multicentre, randomised, double-blind, parallel-group study comparing the efficacy and safety of cerivastatin 0.4 mg/day and cerivastatin 0.2 mg/day in patients with primary hypercholesterolaemia. Exploratory analysis in this study suggested a gender difference in the 0.4 mg group: mean low-density lipoprotein cholesterol (LDL-C) decreased by 44.4 +/- 8.9% in women, compared with a mean decrease of 37.0 +/- 0.9% in men (p < 0.046). This paper reports the results of further sub-analyses from this study. Overall in the per-protocol (PP) population, 71.5% (n = 73) of women taking cerivastatin 0.4 mg had an LDL-C decrease of > 40%, compared with 38.0% (n = 76) of men taking the same dose. In the cerivastatin 0.2 mg PP population, 34% (n = 17) of women had an LDL-C decrease of > 40%, compared with 19% (n = 18) of men. Mean LDL-C/HDL-C ratio decreased by 43% from baseline to the end of the study in the cerivastatin 0.4 mg PP group: -41.3% in males vs. -48.3% in females. In the cerivastatin 0.2 mg group, the decrease in LDL-C/HDL-C ratio from baseline to endpoint did not markedly differ between genders: -37.0% for males vs. -37.3% for females. Categorial analysis of the LDL-C/HDL-C ratio found that 90% of PP patients taking cerivastatin 0.4 mg, and 84% of PP patients taking cerivastatin 0.2 mg, had a low CHD risk (defined as a LDL-C/HDL-C ratio < or = 3) after 8 weeks of treatment. The 6th and 95th percentiles of the distribution of LDL-C reduction from baseline revealed that 90% of PP patients taking cerivastatin 0.4 mg had an LDL-C reduction of between 22% and 56%. The mean LDL-C reduction for this 90% subset of patients was 40.1%. The same analysis for PP patients taking cerivastatin 0.2 mg found that 90% had an LDL-C reduction of between 13% and 49%. The mean LDL-C reduction in this 90% subset of patients was 31.5%. Of the patients taking cerivastatin 0.4 mg and valid for treatment according to National Cholesterol Education Program (NCEP) criteria, 71% (149/211) achieved NCEP targets for LDL-C at Week 16.

Adult↗

Search for variants of the gene-promoter and the potential phosphotyrosine encoding sequence of the insulin receptor substrate-2 gene: evaluation of their relation with alterations in insulin secretion and insulin sensitivity.

AIMS/HYPOTHESIS: The aim of this study was to screen part of the putative promoter sequence in addition to 14 potential phosphotyrosine residues of human IRS-2 for genetic variability which might cause changes in protein expression or function. Furthermore, the potential impact on insulin secretion and sensitivity of a previously identified IRS-2 variant (Gly1057Asp) was analysed. METHODS: The screenings were carried out by the SSCP-heteroduplex technique on DNA from Type II (non-insulin-dependent) diabetic patients. The impact of the Gly1057Asp variant was analysed in four glucose-tolerant Scandinavian study groups. RESULTS: The results showed no nucleotide substitutions in the promoter sequence, however, a novel heterozygous amino acid variant was identified (Leu647Val). In an association study, the new variant was found in 3 of 413 diabetic patients and in none of 280 glucose tolerant subjects. The variant did not affect the binding of IRS-2 to the insulin receptor or p85alpha of phosphatidylinositol 3-kinase when measured in the yeast two-hybrid system. Examination of the common Gly1057Asp variant in 363 young healthy subjects and in 228 glucose tolerant offspring of one diabetic parent showed no differences in insulin secretion or insulin sensitivity after an intravenous glucose tolerance test. Glucose tolerant middle-aged subjects homozygous for the polymorphism (n = 31), however, had on average a 25 % decrease in fasting serum insulin concentrations (p = 0.009) and 28 % (p = 0.01) and 34 % (p = 0.003) reductions in serum insulin concentrations at 30 and 60 min, respectively, during an OGTT compared with wildtype carriers (n = 107). In a cohort of 639 elderly Swedish men the amino acid variant did not have any detectable impact on insulin secretion after an OGTT. CONCLUSION/INTERPRETATION: No genetic variability was found in the IRS-2 promoter. A rare IRS-2 variant at codon 647 has been identified in Type II diabetic patients. The prevalent codon 1057 polymorphism had no consistent effect on insulin secretion or insulin sensitivity. [Diabetologia (1999) 42: 1244-1249]

Adolescent↗

C4 null alleles and myocardial infarction.

The classical risk factors, hypercholesterolemia, smoking, hypertension and diabetes, explain only a part of the epidemiological features of atherosclerotic coronary heart disease. Investigations in the past few years have shown involvement of immunological mechanisms in atherosclerosis. Circulating immune complexes accelerate atherosclerosis both in experimental animal models and in humans. The fourth component of complement (C4) plays an important role in the solubilisation and elimination of immune complexes. C4 consists of two allotypes, C4A and C4B. An earlier report showed an association between C4B null alleles (C4B*Q0) and myocardial infarction and to infarction related mortality. In the present investigation, C4A*Q0 and C4B*Q0 were studied in two population samples. The first (Group I) was a cross sectional study of 100 consecutive males with myocardial infarction before the age of 45 years and 164 population based healthy controls, age and sex matched. The second (Group II) was a nested case control study in which a cohort of 50 year-old males were followed for 20 years for development of myocardial infarction between 50-60 and 60-70 years, and the results compared with those who did not develop MI. We observed no association of homozygous and/or heterozygous C4A*Q0 or C4B*Q0 with myocardial infarction occurring in the age groups < 45, 50-60 and 60-70 years or with the infarction related mortality (P > 0.05). The prevalence/frequency of C4A*Q0 and C4B*Q0 was not related to the age at which MI occurred. The prevalence of C4A*Q0 was not affected by age. We thus conclude that partial deficiency of C4 does not appear to be a major risk factor for myocardial infarction.

Adult↗

The haemodynamic response to hyperinsulinaemia in hypertensive subjects.

In order to study if the vasodilatory action of insulin is impaired in essential hypertension, 24 untreated patients were challenged with a 2 h euglycaemic hyperinsulinaemic clamp (56 E/m2). Cardiac index (CI) was measured by thoracic impedance cardiography and leg blood flow (LBF) by Doppler ultrasound. During the clamp procedure a significant decline in blood pressure was seen (3.0-5.6% over 120 min, P < 0.001). However, no significant effects on ejection fraction (+6 +/- 8 s.d.%), CI (-1 +/- 2%), heart rate (+2 +/- 1%) or total peripheral resistance (TPRI, -0.5 +/- 2%) were found. LBF increased by 22 +/- 35% (P < 0.005). These haemodynamic effects of insulin were not related to age, sex, body mass index, blood pressure or the insulin-mediated glucose uptake during the clamp. In conclusion, insulin increased LBF, but no changes in CI and TPRI were seen in the hypertensive patients. Furthermore, no association between the ability of insulin to induce vasodilatation and to promote glucose uptake was seen.

Fasting↗

The influence of different antihypertensive drugs on left ventricular hypertrophy in a population sample of elderly men.

AIMS AND METHODS: To evaluate if the effects of long-term treatment with different antihypertensive drugs on left ventricular (LV) hypertrophy seen in meta-analysis could also be found in a cross-sectional study of elderly men, we investigated 584 70-year-old men with echocardiography of which 179 were treated for hypertension. RESULTS: Men on antihypertensive treatment showed a significantly higher LV mass than normotensive men (143 +/- 29 vs 132 +/- 28 g/m2, P < 0.01), but no significant difference in LV mass was seen between men on one antihypertensive drug (n = 129) and those on two drugs (n = 47). Among the men on monotherapy, no differences in LV mass between the subjects who were treated with calcium-antagonists (142 +/- 27 g/m2, n = 37), beta-blockers (140 +/- 29 g/m2, n = 66) or ACE-inhibitors (142 +/- 33 g/m2, n = 20) were found. Neither did blood pressure differ between these groups. Excluding subjects with coronary heart disease did not alter the results. Thiazides as monotherapy was uncommon in this population (n = 4) and therefore not evaluated. CONCLUSION: In a population sample of elderly men with hypertension, no differences in LV mass or blood pressure could be seen between subjects treated with ACE-inhibitors, calcium-antagonists or beta-blockers as monotherapy. In meta-analysis of the effects of different antihypertensive therapies on regression of LV hypertrophy, ACE-inhibitors have shown the best results.

Adrenergic beta-Antagonists↗

Skeletal muscle angiotensin-converting enzyme and its relationship to blood pressure in primary hypertension and healthy elderly men.

The aim of this study was to investigate the relationships between angiotensin-converting enzyme (ACE) activity in serum and skeletal muscle to blood pressure and the long-term antihypertensive effects of fosinopril and atenolol. We examined 50 hypertensive patients randomized to receive 20 mg fosinopril or 50 mg atenolol daily for 16 weeks. ACE activity was measured in biopsy specimens from skeletal muscle. Measurements of office and ambulatory blood pressure, serum ACE, and left ventricular wall thickness were also performed. The same investigations were performed in a cross-sectional study of 50 healthy elderly men. Muscle ACE correlated inversely to blood pressure in cross-sectional analyses in both populations (p < 0.05). During atenolol treatment muscle ACE activity tended to increase (14%, p = 0.059), and this increase correlated inversely to the changes in standing systolic and diastolic blood pressure (r = -0.62, p = 0.0044, and r = 0.54, p = 0.016, respectively). Muscle ACE was also inversely correlated to left ventricular wall thickness when the two populations were pooled (r =-0.29, p = 0.0053). In the fosinopril group, muscle ACE activity was not different during treatment than at baseline (-2. 1%, p = 0.68). The inverse relationship between blood pressure and muscle ACE levels in this study indicate that muscle tissue ACE levels are influenced by haemodynamic factors in humans.

Aged↗

Study on COgnition and Prognosis in the Elderly (SCOPE).

The Study on COgnition and Prognosis in the Elderly (SCOPE) is a multicentre, prospective, randomized, double-blind, parallel-group study designed to compare the effects of candesartan cilexetil and placebo in elderly patients with mild hypertension. The primary objective of the study is to assess the effect of candesartan cilexetil on major cardiovascular events. The secondary objectives of the study are to assess the effect of candesartan cilexetil on cognitive function and on total mortality, cardiovascular mortality, myocardial infarction, stroke, renal function, hospitalization, quality of life and health economics. Male and female patients aged between 70 and 89 years, with a sitting systolic blood pressure (SBP) of 160-179 mmHg and/or diastolic blood pressure (DBP) of 90-99 mmHg, and a Mini-Mental State Examination (MMSE) score of 24 or above, are eligible for the study. The overall target study population is 4000 patients, at least 1000 of whom are also to be assessed for quality of life and health economics data. After an open run-in period lasting 1-3 months, during which patients are assessed for eligibility and those who are already on antihypertensive therapy at enrolment are switched to hydrochlorothiazide 12.5 mg o.d., patients are randomized to receive either candesartan cilexetil 8 mg once daily (o.d.) or matching placebo o.d. At subsequent study visits, if SBP remains >160 mmHg, or has decreased by <10 mmHg since the randomization visit, or DBP is >85 mmHg, study treatment is doubled to candesartan cilexetil 16 mg o.d. or two placebo tablets o.d. Recruitment was completed in January 1999. At that time 4964 patients had been randomized. All randomized patients will be followed for an additional 2 years. If the event rate is lower than anticipated, the follow-up will be prolonged.

Aged↗

Efficacy and safety of cerivastatin, 0.2 mg and 0.4 mg, in patients with primary hypercholesterolaemia: a multinational, randomised, double-blind study. Cerivastatin Study Group.

Elevated serum cholesterol level is a key risk factor for cardiovascular morbidity and mortality. Cerivastatin is a highly effective lipid-lowering agent currently licensed at doses of 0.1, 0.2, 0.3 and 0.4 mg. This was a multicentre, randomised, double-blind, parallel-group study comparing the efficacy and safety of cerivastatin 0.4 mg/day with that of cerivastatin 0.2 mg/day in patients with primary hypercholesterolaemia. There was a six-week placebo run-in phase followed by a 24-week active treatment phase. A total of 494 patients were randomised to receive cerivastatin 0.4 mg (n = 332) or 0.2 mg (n = 162). Per-protocol (PP) analysis revealed that mean low-density lipoprotein cholesterol (LDL-C) level decreased by 38.4 +/- 0.7% from baseline in the 0.4 mg group, compared with a decrease of 31.5 +/- 0.9% in the 0.2 mg group (p < 0.0001). There was a significant gender difference in the 0.4 mg group: LDL-C decreased by 44.4 +/- 8.9% in women, compared with a decrease of 37.0 +/- 0.9% in men (p < 0.046). In the PP group as a whole, total cholesterol decreased by 26.0 +/- 0.5% from baseline in the 0.4 mg group, compared with a decrease of 21.6 +/- 0.7% in the 0.2 mg group (p < 0.0001). Both doses were well tolerated; only eight (2.4%) patients in the 0.4 mg group and five (3.1%) patients in the 0.2 mg group withdrew owing to adverse events. Cerivastatin 0.2 mg/day and 0.4 mg/day was found to lower low-density lipoprotein cholesterol and total cholesterol levels in a dose-dependent manner, with both doses exhibiting a good safety profile.

Adult↗

GH but not IGF-I or insulin increases lipoprotein lipase activity in muscle tissues of hypophysectomised rats.

Changes in GH secretion are associated with changes in serum lipoproteins, utilisation of fuels and body composition. Since lipoprotein lipase (LPL) is a key enzyme in the regulation of lipid and lipoprotein metabolism, changes in LPL activity may contribute to these effects of GH. The present study was undertaken to investigate the role of GH and the GH-dependent growth factor, IGF-I, in the regulation of LPL in heart, skeletal muscle and adipose tissue. Female rats were hypophysectomised at 50 days of age. One week later, hormonal therapy was commenced. All hypophysectomised rats received l-thyroxine and cortisol. Adipose tissue, the heart, soleus and gastrocnemius muscles were excised after 1 week of hormonal therapy. The effect of insulin injections on adipose tissue and heart LPL activity was also studied. In separate experiments, LPL activity in post-heparin plasma was measured. Hypophysectomy had no effect on adipose tissue LPL activity, whereas activity was reduced in heart, soleus and gastrocnemius muscle tissues. GH treatment had no significant effect on LPL activity in adipose tissue or soleus muscle, but increased the LPL activity in heart and gastrocnemius muscle. GH treatment increased post-heparin plasma LPL activity. Recombinant human IGF-I treatment (1.25 mg/kg per day) markedly reduced LPL activity in adipose tissue, but had no effect in muscle tissues. The effect of IGF-I treatment on adipose tissue LPL was not reflected by a decrease in post-heparin plasma LPL activity. Daily injections of insulin for 7 days increased LPL activity in adipose tissue but had no effect on heart LPL activity. In adipose tissue, LPL mRNA levels tended to decrease as a result of IGF-I treatment. In the muscle tissues, no significant effects of hypophysectomy, GH or IGF-I treatment on LPL mRNA levels were observed.%It is concluded that GH increases heart and skeletal muscle tissue LPL activity, which probably contributes to an increased post-heparin plasma LPL activity. The effect of GH on muscle LPL activity is probably not mediated by IGF-I or insulin. Insulin and IGF-I have opposite effects on LPL activity in adipose tissue.

Adipose Tissue↗

Impaired systolic and diastolic function and ventricular arrhythmia are common in normotensive healthy elderly men with left ventricular hypertrophy.

BACKGROUND: The present study was designed to assess the impact of left ventricular hypertrophy (LVH) independent of hypertension on the presence of silent myocardial ischemia and arrhythmia, as well as on systolic and diastolic function in otherwise healthy elderly men. METHODS AND RESULTS: Twenty apparently healthy normotensive subjects with LVH were compared with 18 hypertensive subjects with LVH and with 20 healthy subjects without LVH (controls)--all recruited from a health screening programme of 70-year-old men. All participants were free from known coronary heart disease and were evaluated by means of echocardiography with Doppler, a symptom-limited exercise test and 24 h ambulatory ECG monitoring. The healthy normotensive subjects with LVH showed impaired systolic function (ejection fraction 66 +/- 8 (SD)% versus 72 +/- 8% in controls, P < 0.03) and impaired diastolic function (E/A ratio 0.86 +/- 0.20 versus 1.12 +/- 0.30, P < 0.01) as well as an increased number of premature ventricular complexes in the exercise test and during the 24 h ECG monitoring (P < 0.05), when compared with the healthy group without LVH. The hypertensive subjects with LVH showed impaired diastolic function (P < 0.05) and a more pronounced ST depression in the exercise test (P < 0.05), when compared with the healthy group without LVH. In both of the LVH groups, more than 20% of the subjects evidenced ST-segment depression > or = 1 mm in the exercise test, compared with 5% of the healthy group without LVH. CONCLUSIONS: In elderly men free from hypertension or other known disease, LVH at echocardiography was associated with impaired systolic and diastolic function as well as with ventricular arrhythmia. Thus, even in the absence of hypertension, LVH may be a harmful characteristic in the elderly.

Aged↗

Moxonidine improves insulin sensitivity in insulin-resistant hypertensives.

OBJECTIVE: To study whether insulin sensitivity and insulin response are altered by moxonidine treatment in obese patients with mild essential hypertension. DESIGN: a prospective, double-blind, placebo-controlled, randomized, parallel group study. PATIENTS AND METHODS: 77 patients with mild essential hypertension and body mass index > 27 were enrolled. A placebo run-in period of 1-3 weeks was followed by 8-9 weeks of double-blind treatment with either placebo or moxonidine. Patients receiving antihypertensive drugs underwent a 4-week wash-out period preceeding the placebo run-in. Insulin sensitivity was evaluated by hyperinsulinaemic euglycaemic clamp test. Insulin response was measured during intravenous glucose tolerance test. RESULTS: 72 patients completed the study. No serious adverse events were reported. The glucose infusion rate (M value), and insulin sensitivity index (M/I ratio) increased in the moxonidine-treated subjects by 10% (P = 0.025), and 11% (P = 0.04), respectively, whereas the values in the placebo group remained unchanged. In the predefined insulin-resistant subgroup with M/I ratio < 3.6 at baseline, glucose infusion rate and insulin sensitivity index increased by 21% whereas values in the placebo group remained unchanged. A between-group comparison showed a statistical significant difference in the M value (P = 0.026) and a borderline statistical difference in the M/I ratio (P = 0.056) in favour of moxonidine. No statistically significant effects were seen in the subgroup with a M/I ratio > or = or 3.6 at baseline. The insulin secretion in response to glucose stimulation was unaffected in insulin-resistant as well as in insulin-sensitive hypertensive patients. CONCLUSION: Moxonidine treatment improved insulin sensitivity in insulin-resistant, obese patients with mild hypertension, but not in insulin-sensitive obese subjects with mild hypertension, when compared to placebo. Insulin response to glucose stimulation was unaffected. The drug was well tolerated.

Adolescent↗

Local vasodilatation with metacholine, but not with nitroprusside, increases forearm glucose uptake.

Insulin is known to increase blood flow in parallel to glucose uptake in skeletal muscle. However, it is not known if an increase in blood flow by itself is associated with an increase in glucose uptake in the absence of hyperinsulinemia. To investigate further this matter, the effect of increased blood flow on forearm glucose uptake was studied in the fasting state during intra-arterial infusions of two different vasodilators, metacholine and nitroprusside, in 19 hypertensive subjects. Both metacholine (4 microg/min) and nitroprusside (10 microg/min) increased resting forearm blood flow, measured by venous occlusion plethysmography, to a similar degree (180 % and 170 %, respectively, p<0.0001 for both). However, metacholine infusion increased the forearm glucose uptake from 2.0+/-0.9 (S.D.) during rest to 5.5+/-3.0 umol/min/100 ml tissue (p<0.0001), while no significant change in glucose uptake was seen during nitroprusside infusion (2.3+/-1.4 micromol/min/100 ml tissue). In conclusion, vasodilatation induced by metacholine, but not by nitroprusside, increased glucose uptake in the forearm of hypertensive patients. Thus, an increase in forearm blood flow does not necessarily improve glucose uptake in the forearm during the fasting state.

Adult↗

The effect of euglucaemic hyperinsulinaemia on forearm blood flow and glucose uptake in the human forearm.

Insulin-mediated stimulation of blood flow to skeletal muscle has been proposed to be of major importance for insulin-mediated glucose uptake. The aim of this study was to investigate the relative importance of blood flow and glucose extraction as determinants of insulin-mediated glucose uptake in the human forearm. Forearm blood flow (FBF), glucose extraction and oxygen consumption were evaluated for 100 min during the euglycaemic hyperinsulinaemic clamp (92 mU/l) in nine healthy subjects. FBF was measured by venous occlusion plethysmography. Forearm glucose uptake increased sevenfold during the hyperinsulinaemia (P<0.001). Forearm glucose extraction showed a minor increase during the first 10 min of hyperinsulinaemia, but the most marked increase took place between 10 and 20 min (+170%). Thereafter, only a minor further increase was seen. During the first 10 min of hyperinsulinaemia FBF was unchanged. Thereafter, FBF increased steadily to a plateau reached after 60 min (+50%, P<0.001). A close relationship between whole body glucose uptake and FBF was seen at the end of the clamp (r = 0.75, P<0.02), but at this time the relationship between whole body glucose uptake and forearm glucose extraction was not significant. The modest increase in O2 consumption seen at the beginning of the clamp (+19%) was not related to FBF during the early phase of the clamp. In conclusion, the early course of insulin-mediated glucose uptake in the human forearm was mainly due to an increase in glucose extraction. However, with time the insulin-mediated increase in blood flow increased in importance and after 100 min of hyperinsulinaemia FBF was the major determinant of glucose uptake.

Adult↗

Insulin resistance in essential hypertension is related to plasma renin activity.

A high plasma renin activity (PRA) has previously been related to several cardiovascular risk factors as well as to later cardiovascular events. As insulin resistance has been suggested as the unifying factor in the insulin resistance metabolic syndrome, insulin resistance was evaluated by the euglycaemic hyperinsulinaemic clamp technique in 50 untreated hypertensive subjects in whom PRA and serum aldosterone were measured together with lipids and an intravenous glucose tolerance test (IVGTT). PRA was inversely related to insulin-mediated glucose disposal during the clamp (r=-0.31, P < 0.05), as well as to fasting insulin (r=0.32, P < 0.05) and to insulin at 60 min at the IVGTT (r=0.30, P < 0.05), but not to other risk factors. Serum aldosterone was not related to any of the metabolic risk factors. In conclusion, the present investigation showed that insulin resistance is associated with elevated levels of PRA in patients with untreated essential hypertension. It thus seems as if a high activity in the renin system should be included in the disturbances included in the insulin resistance metabolic syndrome, a syndrome with a major impact on future cardiovascular events.

Aged↗

High blood pressure and muscle morphology/metabolism--causal relationship or only associated factors?

As muscle tissue constitutes a main target organ for glucose metabolism and is responsible for the development of insulin resistance, it seems plausible to elucidate the relationship between blood pressure and muscle morphology and metabolism. The association between blood pressure and capillarization/morphology of the vastus lateralis muscle and metabolic variables was evaluated in 24 perimenopausal obese women [body mass index (BMI) 34.9 +/- 1.1; waist-hip ratio (WHR) 0.90 +/- 0.02]. The muscle enzyme activity of lipoprotein lipase (LPL), citrate synthase and glycogen synthase was determined. There was a significant negative correlation between the percentage of type I fibres and relative fibre area of type I on the one hand and systolic and diastolic blood pressure on the other. There was a negative correlation between the capillary density (i.e. number of capillaries/muscle fibre) and a positive correlation between the diffusion distance (fibre area supplied by one capillary) and diastolic blood pressure. The activities of LPL and citrate synthase were positively correlated with the percentage of type I and negatively correlated with the percentage of type II muscle fibres. The activity of LPL was also negatively correlated with plasma glucose and the insulin/C-peptide ratio. The insulin/C-peptide ratio was positively correlated with the percentage of type II muscle fibres. In stepwise multiple regression analyses, 20-30% of the variation in systolic and diastolic blood pressure could be explained by the variables of muscle fibre distribution. Excluding muscle morphological variables from the regression model, the insulin/C-peptide ratio accounted for 13% of the variation in systolic and diastolic blood pressure. The results of the study show the close association between muscle morphology and blood pressure. It remains to be elucidated whether this association indicates a causal relationship.

Adult↗