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P F Plouin

Publications and source records attributed to P F Plouin.

At least 19 recordsLinked to original sources
PubMed2003

Isolated systolic hypertension: data on a cohort of young subjects from a French working population (IHPAF).

Elderly patients with isolated systolic hypertension (ISH)--systolic blood pressure (SBP) > or =140 mmHg and diastolic blood pressure (DBP) <90 mmHg--have increased mortality and morbidity. The aim was to study the incidence of ISH in a younger population of between 15 and 60 years of age, and to measure pulse pressure (PP), mean arterial pressure (MAP) and heart rate (HR) in these subjects. The study population consisted of 27 783 subjects, aged 15-60 years, untreated for hypertension (HT) from a cohort of employees formed to study the incidence of HT in the French working population (AIHFP). BP and HR were measured with a validated, automatic device after 5, 6 and 7 min at rest. The prevalence of ISH was 6.9% in men, 2.3% in women. This prevalence was over 5% in young men and increased at 40-44 years; it was negligible in young women, but increased at 50-54 years to about 10% (ie to the same level as in men of the same age): PP in subjects with ISH (46.9 mmHg) was significantly higher than in the normotensive group (NT-40.9 mmHg); it was comparable in both young men (65.5 mmHg) and older men (66 mmHg); it was higher in men (63.1 mmHg) than in women (61.5 mmHg). HR was higher in ISH than in NT and it was higher in women ( approximately 5 bpm) in whom it decreased with age. The prevalence of ISH is not negligible in HT (30% men, 25% women), with a high prevalence in young subjects and elevated PP, MAP and HR values. These data should be taken into account as elevated ISH, PP and HR are considered as cardio-vascular risk factors.

Adolescent↗
PubMed2003

Telmisartan vs losartan plus hydrochlorothiazide in the treatment of mild-to-moderate essential hypertension--a randomised ABPM study.

The objective of this prospective, randomised, open-label, blinded-end point parallel-group, multicentre study was to show that telmisartan 80 mg is not inferior to a fixed-dose combination of losartan 50 mg/hydrochlorothiazide (HCTZ) 12.5 mg in patients with mild-to-moderate hypertension. The criterion for noninferiority was a treatment difference of < or =3.0 mmHg in the reduction of 24-h mean ambulatory diastolic blood pressure (DBP) from the end of the 4-week placebo washout period to the end of the 6-week active treatment period. In the intent-to-treat analysis, the mean reduction in 24-h DBP was 8.3+/-6.7 mmHg among telmisartan-treated patients (n=332) and 10.3+/-6.3 mmHg among losartan/HCTZ-treated patients (n=350). The mean adjusted difference in 24-h DBP between the two treatment groups was 1.9 mmHg, allowing rejection of the a priori null hypothesis of a treatment difference of >3 mmHg. The reduction in mean 24-h systolic blood pressure was 13.2+/-10.2 mmHg with telmisartan and 17.1+/-10.3 mmHg with losartan/HCTZ. Both drugs provided effective control over the 24-h dosing interval. Analyses of morning (0600-1159) ambulatory blood pressure monitoring DBP means and trough cuff DBP confirmed the noninferiority hypothesis of the protocol for telmisartan 80 mg vs losartan 50 mg/HCTZ 12.5 mg. The reductions in office blood pressures measured at trough in patients treated with telmisartan were -16.3/-9.6 and -18.5/-11.1 mmHg in the patients treated with losartan/HCTZ (difference -2.4/-1.2 mmHg). There were no differences between the side-effect profiles of the two treatments.

Aged↗
PubMed2002

[Arterial hypertension secondary to curable causes in adults].

EXTENSIVE AND COSTLY INVESTIGATIONS: Are not warranted in the vast majority of hypertensive patients. Characteristics identifying the patients at risk for secondary hypertension can be used to define the small percentage of patients with hypertension who require more extensive diagnostic testing and management of their condition. Exposure to certain medicines, foods or drugs may cause reversible rises in blood pressure. Renovascular and adrenal diseases cause curable forms of hypertension. IN MANY CASES, THE PATIENT'S HISTORY: Examination and simple tests can detect such exposures and disorders. Checking for secondary hypertension is therefore an early step required for the management of all patients with hypertension, provided it is based on clinical signs and inexpensive tests. This primary screening cannot exclude the possibility of renovascular or adrenal disease in a small number of asymptomatic patients. The risk of missing a diagnosis is acceptable provided that blood pressure is normalized by non-specific antihypertensive treatment. However, more extensive etiologic investigation is required in patients who subsequently develop resistant hypertension. This secondary screening requires imaging and biochemical tests that are not required for primary screening. CORRECTION OF THE CAUSES: Of secondary forms of hypertension may restore blood pressure to normal. The patient's age affects the reversibility of renovascular and adrenal hypertension after etiologic treatment: the younger the patient, the higher the probability of blood pressure normalization.

Adenoma↗
PubMed2002

[Management of atherosclerotic renal artery stenoses].

Patients with atherosclerotic renal artery stenosis may develop hypertension, recurrent pulmonary edema and chronic renal failure, but have a much higher risk of dying from stroke or myocardial infarction than of progressing to end-stage renal disease. Indeed, atherosclerotic renal artery stenosis typically occurs in high risk patients with coexistent vascular disease elsewhere. Recent controlled trials comparing medication to revascularization have shown that only a minority of such patients can expect hypertension cure, whereas the results of trials designed to document the ability of revascularization to prevent progressive renal failure are not yet available. Revascularization should be undertaken in patients with atherosclerotic renal artery stenosis and resistant hypertension or heart failure, and probably in those with rapidly deteriorating renal function or with an increase in plasma creatinine levels during angiotensin-converting enzyme inhibition, especially if their renal resistance--index before revascularization is less than 80. With or without revascularization, medical therapy using antihypertensive agents, statins and aspirin is necessary in almost all cases.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2002

[Endocrine hypertension in pregnancy].

Hypertension is a frequent complication of pregnancy and may compromise fetal and maternal outcome. Hypertension may be pregnancy-induced, essential or secondary to endocrine disorders. Most cases of endocrine hypertension are the consequence of adrenal diseases. Pheochromocytoma, hypercorticism, primary aldosteronism or glucocorticoid-remediable aldosteronism can be present or diagnosed at any term and may cause severe hypertension. The most hazardous form of endocrine hypertension during pregnancy is pheochromocytoma because it may involve paroxysmal arrhythmia and/or hypertension during labor. Clinical clues and biological tests are similar to those used in non-pregnant subjects. Tests for tumor location are limited to ultrasound and magnetic resonance scans in order to avoid maternal and fetal irradiation. Medication to prepare for pheochromocytoma surgery uses alpha- and beta-blockers. The timing of surgery depends on the term of pregnancy at the diagnosis of the tumor.

Adrenal Gland Neoplasms↗
PubMed2001

The R22X mutation of the SDHD gene in hereditary paraganglioma abolishes the enzymatic activity of complex II in the mitochondrial respiratory chain and activates the hypoxia pathway.

Hereditary paragangliomas are usually benign tumors of the autonomic nervous system that are composed of cells derived from the primitive neural crest. Even though three genes (SDHD, SDHC, and SDHB), which encode three protein subunits of cytochrome b of complex II in the mitochondrial respiratory chain, have been identified, the molecular mechanisms leading to tumorigenesis are unknown. We studied a family in which the father and his eldest son had bilateral neck paragangliomas, whereas the second son had a left carotid-body paraganglioma and an ectopic mediastinal pheochromocytoma. A nonsense mutation (R22X) in the SDHD gene was found in these three affected subjects. Loss of heterozygosity was observed for the maternal chromosome 11q21-q25 within the tumor but not in peripheral leukocytes. Assessment of the activity of respiratory-chain enzymes showed a complete and selective loss of complex II enzymatic activity in the inherited pheochromocytoma, that was not detected in six sporadic pheochromocytomas. In situ hybridization and immunohistochemistry experiments showed a high level of expression of markers of the angiogenic pathway. Real-time quantitative reverse transcriptase (RT)-PCR measurements confirmed that vascular endothelial growth factor and endothelial PAS domain protein 1 mRNA levels were significantly higher (three- and sixfold, respectively) than those observed in three sporadic benign pheochromocytomas. Thus, inactivation of the SDHD gene in hereditary paraganglioma is associated with a complete loss of mitochondrial complex II activity and with a high expression of angiogenic factors.

Adult↗
PubMed2001

[Revascularization of atherosclerotic stenosis of the renal artery. Indications and results].

RISKS: Atherosclerotic renal artery stenosis typically occurs in high risk patients with coexistent vascular disease elsewhere. Patients with atherosclerotic renal artery stenosis may develop progressive renal failure but have a much higher risk of dying with a stroke or a myocardial infarction than of progressing to end-stage renal disease. REVASCULARIZATION RESULTS: Recent controlled trials comparing medication to revascularization have shown that only a minority of such patients can expect hypertension cure, whereas trials designed to document the ability of revascularization to prevent progressive renal failure are not yet available. Percutaneous renal artery angioplasty is the first choice because it is simpler than and as effective as surgical reconstruction. INDICATIONS: Revascularization should be undertaken in patients with atherosclerotic renal artery stenosis and resistant hypertension or heart failure, and probably in those with rapidly deteriorating renal function or with an increase in plasma creatinine levels during angiotensin-converting enzyme inhibition. Older age, long history of hypertension and a kidney size less than 8 cm are associated with little chance of blood pressure improvement or kidney function recovery. PRACTICAL ATTITUDE: With or without revascularization, medical therapy using antihypertensive agents, statins and aspirin is necessary in almost all cases. Blood pressure and plasma creatinine concentration should be measured every three months. Kidney size and renal artery patency should be assessed yearly.

Arteriosclerosis↗
PubMed2001

Molecular markers and long-term recurrences in a large cohort of patients with sporadic adrenocortical tumors.

Genetic alterations, such as loss of heterozygosity (LOH) at the 17p13 and 11p15 loci and overexpression of the insulin-like growth factor (IGF)-II gene, are associated with the malignant phenotype in sporadic adrenocortical tumors. A high risk of recurrence after surgery for adrenocortical tumors is predicted in cases with regional invasion or distant metastases. However, patients with localized tumors also have a high risk of recurrence. Reliable prognostic markers are required to identify subjects at high risk of recurrence. The aim of this study was to assess the prognostic value of three molecular markers (17p13 LOH, 11p15 LOH, and overexpression of the IGF-II gene) by assessing disease-free survival in a large series of adult patients with sporadic adrenocortical tumors. Adult patients (114) were prospectively followed up from diagnosis of the disease to June 1999 or to death. Malignancy was initially diagnosed in 18 patients (McFarlane stage III: n = 1 and stage IV: n = 17). The remaining 96 patients with localized adrenal disease at diagnosis (stage I: n = 60 and stage II: n = 36) were at risk of recurrence. Histological grade was assessed according to Weiss criteria, and tumors were classified into two groups (Weiss score or=4). Tumor samples were analyzed for LOH at the 17p13 and 11p15 loci and for IGF-II gene mRNA content. 17p13 LOH was a strong predictor of shorter disease-free survival in univariate analysis (P = 0.001; relative risk, 27), as were histological grade (Weiss score >or=4; P = 0.00001; relative risk, 15), 11p15 LOH (P = 0.004; relative risk, 9), tumor size (size >5 cm; P = 0.006; relative risk, 18), and overexpression of the IGF-II gene (P = 0.01; relative risk, 5). In a Cox proportional hazards regression model, histological grade (P = 0.04; relative risk, 4.2) and 17p13 LOH (P = 0.009; relative risk, 21.5) were independently associated with recurrence. Molecular markers, particularly 17p13 LOH, are predictive of long-term outcome in patients with sporadic adrenocortical tumors. In patients who have undergone curative surgery, routine assessment of these tumor markers is a useful complement to histological scoring for predicting recurrence and guiding decisions for subsequent follow-up and management.

Adolescent↗
PubMed2001

Polymorphic differences from normal in the aldosterone synthase gene (CYP11B2) in patients with primary hyperaldosteronism and adrenal tumour (Conn's syndrome).

OBJECTIVE: The hypertension of Conn's syndrome is due to autonomous aldosterone production by a unilateral adrenocortical adenoma. The source of tumour initiation and the reasons for excess aldosterone production as opposed to cortisol are not known, although variations in the promoter region of the gene coding for aldosterone synthase (CYP11B2) might account for the altered rate of aldosterone secretion. DESIGN: In a series (n = 27) of well-characterized Conn's syndrome cases, the aldosterone synthase gene (CYP11B2) was screened by single-strand conformational polymorphism (SSCP) for differences from the consensus sequence. RESULTS: No new mutations were found. The frequencies of two previously described linked polymorphisms, one a change of -344C to T in a putative steroidogenic factor-1 (SF-1) binding site and the other an exchange of intron 2 for that of CYP11B1 (conversion) were measured in tumour and genomic DNA. The frequency of the SF-1 T allele (P < 0.0001) and the conversion allele (P < 0.001) were markedly different between the Conn's syndrome group and the normal controls. However, the frequency did not differ between tumour and genomic DNA in the patient group. CONCLUSION: While it is unlikely that this difference from normal is related to tumour growth, these genotypes may predispose the tumour to aldosterone production.

Adenoma↗
PubMed2001

Is primary aldosteronism underdiagnosed in clinical practice?

1. Primary aldosteronism is a syndrome consisting of hypertension, suppressed renin activity or concentration and high aldosterone levels in plasma or urine. The main steps in diagnosis are the determination of renin and aldosterone levels, the demonstration of renin-aldosterone dissociation and discrimination between idiopathic hyperplasia and Conn's adenoma, with only Conn's adenoma amenable to surgery. 2. Patients with resistant hypertension and/or hypokalaemia should be screened for primary aldosteronism with simple, redundant hormonal tests. The aldosterone to renin ratio is a logical initial screening test, a high ratio demonstrating renin-aldosterone dissociation. Criteria for a high ratio should be determined in each laboratory. 3. In patients with documented primary aldosteronism, computed tomography scan and adrenal vein sampling help to distinguish between idiopathic hyperplasia and Conn's adenoma. 4. Patients with low renin hypertension, idiopathic hyperplasia and Conn's adenoma have overlapping values for plasma concentrations of potassium, renin and aldosterone and the aldosterone to renin ratio. Because primary aldosteronism subtypes are quantitative diseases, the true prevalence of primary aldosteronism cannot be defined. 5. The use of sensitive screening tests (e.g. aldosterone to renin ratio) gives a higher prevalence of diagnosed cases of primary aldosteronism, but not of surgically correctable forms. Therefore, there is no clinical evidence that primary aldosteronism is underdiagnosed. 6. There is a need for tests to predict the postoperative blood pressure outcome of surgery in subjects with Conn's adenoma.

Adrenal Glands↗
PubMed2001

Presentation and revascularization outcomes in patients with radiation-induced renal artery stenosis.

This study analyzed the initial presentation and revascularization outcomes of patients with radiation-induced renal artery stenosis, a rare complication of therapeutic irradiation. Of 11 patients with renal artery stenosis after irradiation, 7 patients fulfilled the following criteria: normotension before irradiation, radiation dose greater than 25 grays delivered to the renal arteries, associated perirenal radiation-induced lesions, and absence of arterial disease outside the radiation field. The median age at irradiation was 30 years, and the median local irradiation dose was 40 grays. The median time from irradiation to referral was 13 years. All patients were hypertensive at referral, with a median blood pressure (BP) of 171/102 mm Hg and median treatment score of two. The median glomerular filtration rate was 67 mL/min. Two patients had bilateral stenoses and 1 patient had stenosis affecting a single kidney. Stenoses were proximal in 6 patients and truncal in 1 patient, and all had the appearance of atherosclerotic stenosis. Percutaneous transluminal renal artery angioplasty (PTRA) was successful in 5 patients, but required multiple insufflations. PTRA failed in 1 patient, who subsequently underwent an aortorenal bypass. After a median follow-up of 36 months, 2 patients had died of noncardiovascular causes and 4 patients remained hypertensive, with a median BP of 136/85 mm Hg and median treatment score of two. No restenosis occurred, but aneurysms developed at the site of angioplasty in 1 patient. If hypertension occurs even decades after irradiation, a radiation-induced renal artery stenosis should be sought in patients who have undergone abdominal irradiation.

Adult↗
PubMed2001

Factors associated with perioperative morbidity and mortality in patients with pheochromocytoma: analysis of 165 operations at a single center.

To identify preoperative factors associated with 30-day morbidity and mortality after pheochromocytoma surgery, we carried out an external review of the records of all patients undergoing pheochromocytoma surgery from 1975 to 1997 at a single center. One hundred and forty-seven patients, including 23 with malignant tumors at the time of the first operation, underwent 165 operations. Death, resection of a neighboring organ, further surgery, secondary transfer to an intensive care unit, and any events associated with a surgical stay exceeding 10 days were defined as complications. Mortality and morbidity were 4 of 165 (2.4%) and 38 of 161 (23.6%), respectively. Morbidity included 13 spleen resections and hematomas. Spleen complications were not related to tumor location, but were probably due to the operative strategy used, a transperitoneal complete abdominal exploration including both adrenal glands. Complications were independently associated with preoperative systolic blood pressure [odds ratio (OR), 1.14/cm Hg], urinary metanephrine excretion (OR, 1.18/10 micromol x day), and with the number of operations (repeat vs. first operation OR, 5.36). In conclusion, pheochromocytoma resection consistently involves a risk of complications. Spleen damage should be prevented by complete preoperative localization studies and an elective or laparoscopic surgical approach. Careful blood pressure control should help prevent complications. Patients with high secretion tumors and those undergoing repeat intervention are at high risk of complications and should be referred to centers familiar with pheochromocytoma management.

Adolescent↗
PubMed2000

High levels of tyrosine phosphorylated proto-ret in sporadic phenochromocytomas.

Pheochromocytomas are tumors originating from chromaffin cells, the large majority of which are sporadic neoplasms. The genetic and molecular events determining their tumorigenesis continue to remain unknown. On the other hand, RET germ-line mutations cause the inheritance of familial tumors in multiple endocrine neoplasia (MEN)-2 diseases, which account for a minority of pheochromocytomas. We investigated the expression of the RET gene in 14 sporadic tumors harboring no activating mutations. A subset of highly RET-expressing tumors (50%) could be distinguished. They showed RET transcript, protein amounts as well as Ret-associated phosphotyrosine levels similar to those measured in MEN-2A-associated pheochromocytomas. We also determined the GDNF and GDNF family receptor alpha (GFRalpha)-1 transcript levels in tumors and in normal tissues. Whereas the GFRalpha-1 transcripts were detected at similar levels in normal tissues and in tumors, GDNF was frequently found expressed in sporadic tumors at levels several times higher than in controls. These results led us to propose the existence of an autocrine or paracrine loop leading to chronic stimulation of the Ret signaling pathway, which could participate in the pathogenesis of a number of sporadic pheochromocytomas.

Adrenal Gland Neoplasms↗
PubMed2000

The long-term effectiveness of preventive strategies for osteoporosis in postmenopausal women: a modeling approach.

Based on data from the literature, we have developed a computer-based simulation model to compare the long-term effectiveness of different preventive strategies of osteoporotic fractures. The Markov model comprises 25 states, including states which describe women distributed according to three levels of fracture risk, fractures states, post-fracture states and a death state. We chose eight standard preventive strategies, which we compare with the 'No Treatment' reference strategy. The first two strategies consist in treating all 50-year-old women for 5 or 10 years with hormone replacement therapy (HRT). Strategies 3 and 4 aim at assessing a 5-year course of treatment with bisphosphonates in osteopenic and osteoporotic 65- or 75-year-old women. Strategies 5 and 6 combine 5 years of HRT in all 50-year-old women with 5 years of bisphosphonates in osteopenic and osteoporotic women at 65 or 75 years. The last two strategies simulate 10 years of HRT in all 50-year-old women, followed by strategy 3 or strategy 4. Simulated life expectancy and mean ages of fracture occurrence fit well with the observed data. All the preventive strategies tested reduced the number of fractures. Early 10-year HRT in all women, plus 5 years of bisphosphonates in women at risk of fractures at 65 or 75 years, are the most effective strategies, with an 18.4-19.0% reduction in all fractures, and a 25.6-26.1% reduction in the number of hip fractures. Strategy 2 has a similar outcome, thus demonstrating the value of treatment started early and sustained over a long period. The strategies implemented later, S3 and S4, only concern women at risk (i.e., osteopenic or osteoporotic), and are less effective, with a 1.5-2.1% decrease in all fractures. The combined strategies, S5 and S6, produce intermediate results: a 12.9-13.5% reduction in the number of all fractures and a 17.5-17.9% reduction in hip fractures.

Aged↗
PubMed2000

Atherosclerotic renal artery stenosis: surgery, percutaneous transluminal angioplasty, or medical therapy?

Atherosclerotic renal artery stenosis typically occurs in high-risk patients with coexistent vascular disease elsewhere. Patients with atherosclerotic renal artery stenosis may develop progressive renal failure but have a much higher risk of dying of stroke or myocardial infarction than of progressing to endstage renal disease. Recent controlled trials comparing medication to revascularization have shown that only a minority of such patients can expect hypertension cure, whereas trials designed to document the ability of revascularization to prevent progressive renal failure are not yet available. Revascularization should be undertaken in patients with atherosclerotic renal artery stenosis and resistant hypertension or heart failure, and probably in those with rapidly deteriorating renal function or an increase in plasma creatinine levels during angiotensin converting enzyme inhibition. With or without revascularization, medical therapy using antihypertensive agents, statins, and aspirin is necessary in almost all cases.

Angioplasty, Balloon↗