Demographic and geographic vascular risk factor differences in European young adults with ischemic stroke: the 15 cities young stroke study.

BACKGROUND AND PURPOSE: We compared among young patients with ischemic stroke the distribution of vascular risk factors among sex, age groups, and 3 distinct geographic regions in Europe. METHODS: We included patients with first-ever ischemic stroke aged 15 to 49 years from existing hospital- or population-based prospective or consecutive young stroke registries involving 15 cities in 12 countries. Geographic regions were defined as northern (Finland, Norway), central (Austria, Belgium, France, Germany, Hungary, The Netherlands, Switzerland), and southern (Greece, Italy, Turkey) Europe. Hierarchical regression models were used for comparisons. RESULTS: In the study cohort (n=3944), the 3 most frequent risk factors were current smoking (48.7%), dyslipidemia (45.8%), and hypertension (35.9%). Compared with central (n=1868; median age, 43 years) and northern (n=1330; median age, 44 years) European patients, southern Europeans (n=746; median age, 41 years) were younger. No sex difference emerged between the regions, male:female ratio being 0.7 in those aged <34 years and reaching 1.7 in those aged 45 to 49 years. After accounting for confounders, no risk-factor differences emerged at the region level. Compared with females, males were older and they more frequently had dyslipidemia or coronary heart disease, or were smokers, irrespective of region. In both sexes, prevalence of family history of stroke, dyslipidemia, smoking, hypertension, diabetes mellitus, coronary heart disease, peripheral arterial disease, and atrial fibrillation positively correlated with age across all regions. CONCLUSIONS: Primary preventive strategies for ischemic stroke in young adults-having high rate of modifiable risk factors-should be targeted according to sex and age at continental level.

Shorter time to diagnosis and improved stage at presentation in Swiss patients with retinoblastoma treated from 1963 to 2004.

OBJECTIVES: Retinoblastoma is the most frequent intraocular malignancy in children. Early diagnosis is essential for globe salvage and patient survival. The aim of our study was to determine how time to diagnosis of retinoblastoma has evolved over a 40-year period in Switzerland. METHOD AND PATIENTS: A retrospective study of 139 Swiss patients with retinoblastoma was performed comparing 3 periods: (1) 1963-1983; (2) 1984-1993; and (3) 1994-2004. Factors taken into account were gender, laterality of retinoblastoma, age at first symptoms, type and first observer of symptoms, time to diagnosis, age at diagnosis, disease stage, and family history. RESULTS: Thirty-seven patients (26.6%) were treated in period 1, 44 (31.7%) in period 2, and 58 (41.7%) in period 3. Overall, the diagnostic interval decreased in a significant way from 6.97 months in period 1 to 3.58 in period 2 and to 2.25 in period 3. When looking separately at unilateral and bilateral disease, the decrease of the diagnostic interval remained statistically significant in unilateral retinoblastoma; there was also a significant reduction in the number of patients with advanced group E disease (Murphree classification) (61.5% in period 1, 46.7% in period 2, 22.2% in period 3). In bilateral disease, the same observations were made to a lesser extent. However, there were no cases with group E disease in 10 patients with positive family history. Leukocoria (48.2%) and strabismus (20.1%) were the 2 most frequent symptoms throughout the 3 periods. The only factors that statistically influenced the chances of having a diagnosis of group E disease were the diagnostic interval and period of diagnosis. CONCLUSIONS: Progress has been made in the diagnosis of retinoblastoma in Switzerland, notably in unilateral disease. Improvement to a lesser extent has also been observed in bilateral cases but without statistical significance. Greater effort is needed to teach physicians-in-training to recognize the importance of ocular symptoms and refer patients earlier.

Frequency and impact of autosomal dominant polycystic kidney disease in the Seychelles (Indian Ocean).

BACKGROUND: As little such data is available in African populations, we investigated the prevalence of ADPKD and the impact of the disease in the Seychelles islands, where approximately 65% of the population is of African descent and 30% of Caucasian or mixed descent. METHODS: Prevalent cases were identified over a 3-year period by requesting all the doctors in the country (most of them are employed within a national health system) to refer all presumed or confirmed cases and by systematically examining the family members of all confirmed cases. The diagnosis was based on standard criteria including ultrasonographic findings and family history. RESULTS: Forty-two cases were identified in this population of 74,331 inhabitants, a total prevalence (per 100,000 total population) of 57 (95% CI, 41-76). All but one of the cases were of Caucasian descent so that the prevalence rates of the disease in the populations of Black and Caucasian descents were respectively 2 (0-11) and 184 (132-249). The prevalence rates of the gene(s) carriers were estimated to be 75 (45-117) in the total population respectively 6 (0-33) and 236 (140-372) in the Black and Caucasian populations. Haplotype analysis in 58 cases from three families showed a common DNA fragment in all affected individuals. Cases had significantly higher blood pressure compared to the general population and 21% had serum creatinine higher than 120 mumol/l. Among the established pedigrees, mean age of death between 1960 and 1995 (haemodialysis was introduced in 1992) was younger in subjects with than those without ADPKD (50.5 vs 67.7 years; P < 0.001). CONCLUSIONS: In the Seychelles, ADPKD clusters in the Caucasian population (possibly a founder effect), is rare in individuals of black descent, and is associated with substantial clinical and survival impact.

Metabolically healthy obesity: different prevalences using different criteria.

To estimate the prevalence of metabolically healthy obesity (MHO) according to different definitions. Population-based sample of 2803 women and 2557 men participated in the study. Metabolic abnormalities were defined using six sets of criteria, which included different combinations of the following: waist; blood pressure; total, high-density lipoprotein or low-density lipoprotein-cholesterol; triglycerides; fasting glucose; homeostasis model assessment; high-sensitivity C-reactive protein; personal history of cardiovascular, respiratory or metabolic diseases. For each set, prevalence of MHO was assessed for body mass index (BMI); waist or percent body fat. Among obese (BMI 30 kg/m(2)) participants, prevalence of MHO ranged between 3.3 and 32.1% in men and between 11.4 and 43.3% in women according to the criteria used. Using abdominal obesity, prevalence of MHO ranged between 5.7 and 36.7% (men) and 12.2 and 57.5% (women). Using percent body fat led to a prevalence of MHO ranging between 6.4 and 43.1% (men) and 12.0 and 55.5% (women). MHO participants had a lower odd of presenting a family history of type 2 diabetes. After multivariate adjustment, the odds of presenting with MHO decreased with increasing age, whereas no relationship was found with gender, alcohol consumption or tobacco smoking using most sets of criteria. Physical activity was positively related, whereas increased waist was negatively related with BMI-defined MHO. MHO prevalence varies considerably according to the criteria used, underscoring the need for a standard definition of this metabolic entity. Physical activity increases the likelihood of presenting with MHO, and MHO is associated with a lower prevalence of family history of type 2 diabetes.

Acute coronary syndromes in young patients: presentation, treatment and outcome.

BACKGROUND: Acute coronary syndromes (ACS) in very young patients have been poorly described. We therefore evaluate ACS in patients aged 35 years and younger. METHODS: In this prospective cohort study, 76 hospitals treating ACS in Switzerland enrolled 28,778 patients with ACS between January 1, 1997, and October 1, 2008. ACS definition included ST-segment elevation myocardial infarction (STEMI), non-ST-segment elevation myocardial infarction (NSTEMI), and unstable angina (UA). RESULTS: 195 patients (0.7%) were 35 years old or younger. Compared to patients>35 years, these patients were more likely to present with chest pain (91.6% vs. 83.7%; P=0.003) and less likely to have heart failure (Killip class II to IV in 5.2% vs. 23.0%; P<0.001). STEMI was more prevalent in younger than in older patients (73.1% vs. 58.3%; P<0.001). Smoking, family history of CAD, and/or dyslipidemia were important cardiovascular risk factors in young patients (prevalence 77.2%, 55.0%, and 44.0%). The prevalence of overweight among young patients with ACS was high (57.8%). Cocaine abuse was associated with ACS in some young patients. Compared to older patients, young patients were more likely to receive early percutaneous coronary interventions and had better outcome with fewer major adverse cardiac events. CONCLUSIONS: Young patients with ACS differed from older patients in that the younger often presented with STEMI, received early aggressive treatment, and had favourable outcomes. Primary prevention of smoking, dyslipidemia and overweight should be more aggressively promoted in adolescence.

Genetics of essential tremor.

Essential tremor (ET) is a prevalent condition manifesting with progressive action tremor. Although ET was traditionally viewed as a sporadic disease, a significant proportion of cases report a positive family history of tremor. Autosomal dominant inheritance can be demonstrated in many families. Previously, genome-wide linkage studies in families mapped three loci for ET, hereditary essential tremor-1 (ETM1), ETM2 and ETM3. However, no causal mutation has been replicated in candidate genes within these loci, including dopamine D3 receptor (DRD3) and HS1-binding protein 3 (HS1BP3). Recently, the first genome-wide association study in ET followed by replication studies conducted in diverse populations identified a significant association between the leucine-rich repeat and Ig domain containing 1 gene (LINGO1) SNP rs9652490 and risk for ET Although further novel variants were indentified in LINGO1 and its paralog LINGO2 that may be associated with risk for ET, the pathogenic mechanisms involved remain elusive. Given the possibility that ET as a complex trait may be influenced by the combined effects of rare variants, novel high-throughput technologies sequencing all exons across the genome (exome sequencing) or the whole genome (genome sequencing) may become crucial in understanding/deciphering the genetic background of ET.

Clinical features of myocardial infarction and myocarditis in young adults: a retrospective study.

OBJECTIVES: To evaluate the prevalence and clinical presentation of myocardial infarction (MI) and myocarditis in young adults presenting with chest pain (CP) and an elevated serum troponin I (TnI) to the emergency department (ED). DESIGN: Retrospective, observational, single-centre study. PARTICIPANTS: All consecutive patients 18-40 years old admitted to the ED for CP with an elevated TnI concentration. PRIMARY OUTCOME MEASURES: Prevalence of MI, myocarditis and the characterisation of clinical presentation. RESULTS: 1588 patients between 18 and 40 years old were admitted to the ED with CP during 30 consecutive months. 49 (3.1%) patients with an elevated TnI (>0.09 μg/l) were included. 32.7% (16/49) were diagnosed with MI (11 ST-elevation myocardial infarction (STEMI) and 5 non-ST-elevation myocardial infarction (NSTEMI)) and 59.2% (29/49) with myocarditis. Compared with patients with myocarditis, MI patients were older (34.1±3.8 vs 26.9±6.4, p=0.0002) with more cardiovascular risk factors (mean 2.06 vs 0.69). Diabetes (18.8% vs 0%, p=0.0039), dyslipidaemia (56.2% vs 3.4%, p<0.0001) and family history of coronary artery disease (CAD) (37.5% vs 10.3% p=0.050) were associated with MI. Fever or recent viral illness were present in 75.9% (22/29) of patients with myocarditis, and in 0% of MI patients (p<0.0001). During follow-up, two patients with myocarditis were re-admitted for CP. CONCLUSIONS: In this study, 32.7% of patients <40-year-old admitted to an ED with CP and elevated TnI had a diagnosis of MI. Key distinctive clinical factors include diabetes, dyslipidaemia, family history of CAD and fever or recent viral illness.

Postpacing abnormal repolarization in catecholaminergic polymorphic ventricular tachycardia associated with a mutation in the cardiac ryanodine receptor gene.

BACKGROUND Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an arrhythmogenic disease for which electrophysiological studies (EPS) have shown to be of limited value.OBJECTIVE This study presents a CPVT family in which marked postpacing repolarization abnormalities during EPS were the only consistent phenotypic manifestation of ryanodine receptor (RyR2) mutation carriers.METHODS The study was prompted by the observation of transient marked QT prolongation preceding initiation of ventricular fibrillation during atrial fibrillation in a boy with a family history of sudden cardiac death (SCD). Family members underwent exercise and pharmacologic electrocardiographic testing with epinephrine, adenosine, and flecainide. Noninvasive clinical test results were normal in 10 patients evaluated, except for both epinephrine- and exercise-induced ventricular arrhythmias in 1. EPS included bursts of ventricular pacing and programmed ventricular extrastimulation reproducing short-long sequences. Genetic screening involved direct sequencing of genes involved in long QT syndrome as well as RyR2.RESULTS Six patients demonstrated a marked increase in QT interval only in the first beat after cessation of ventricular pacing and/or extrastimulation. All 6 patients were found to have a heterozygous missense mutation (M4109R) in RyR2. Two of them, presenting with aborted SCD, also had a second missense mutation (I406T- RyR2). Four family members without RyR2 mutations did not display prominent postpacing QT changes.CONCLUSION M4109R- RyR2 is associated with a high incidence of SCD. The contribution of I406T to the clinical phenotype is unclear. In contrast to exercise testing, marked postpacing repolarization changes in a single beat accurately predicted carriers of M4109R- RyR2 in this family.

Who is at low risk for cardiovascular disease? An assessment of different definitions

Background: There is little information regarding the determinants and trends of the prevalence of low cardiovascular risk factor (RF) profile in the general population. The aim of this study was to assess the prevalence and trends of low RF profile in the Swiss population according to different definitions. Methods: Population-based cross-sectional studies conducted in 1984-6 (N=3300), 1988-9 (N=3331), 1992-3 (N=3133) and 2003-6 (N=6170) and restricted to age group 35-75 years. Seven different definitions of low RF profile were used to assess determinants, while two definitions were used to assess trends. Results: Prevalence of low RF profile varied between 6.5% (95% confidence interval: 5.9-7.1) and 9.7% (9.0-10.5) depending on the definition used. This prevalence was higher than in other countries. Irrespective of the definition used, the prevalence of low RF profile was higher in women and in physically active participants, and decreased with increasing age or in the presence of a family history of cardiovascular disease. Using one definition, the prevalence of low RF profile increased from 3.8% (3.1-4.5) in 1984-6 to 6.7% (6.1-7.3) in 2003-6; using another definition, the results were 5.9% (5.1-6.8) and 9.7% (9.0-10.5), respectively. Conclusion: Switzerland is characterized by a high and increasing prevalence of low RF profile within the age group 35 to 75, irrespective of the criteria used. This high prevalence might partly e

Association of different lipid measures for atherogenic lipid fractions and risk of coronary events in patients receiving combination antiretroviral therapy: the Swiss HIV Cohort Study

Background: Evidence for a better performance of different highly atherogenic versus traditional lipid parameters for coronary heart disease (CHD) risk prediction is conflicting. We investigated the association of the ratios of sma11 dense low density lipoprotein(LDL)/apoplipoprotein A, aolipoprotein B/apolipoprotein A-I and total cholesterol! HDL-cholesterol and CHD events in patients on combination antiretroviral therapy (cART).Methods: Case control study nested into the Swiss HIV Cohort Study: for each cART-treated patient with a first coronary event between April 1, 2000 and July 31, 2008 (case) we selected four control patients (1) that were without coronary events until the date of the event of the index case, (2) had a plasma sample within ±30 days of the sample date of the respective case, (3) received cART and (4) were then matched for age, gender and smoking status. Lipoproteins were measured by ultracentrifugation. Conditional logistic regression models were used to estimate the independent effects of different lipid ratios and the occurrence of coronary events.Results: In total, 98 cases (19 fatal myocardial infarctions [MI] and 79 non-fatal coronary events [53 definite MIs, 15 possible MIs and 11 coronary angioplasties or bypassesJ) were matched with 392 controls. Cases were more often injecting drug users, less likely to be virologically suppressed and more often on abacavir-containing regimens. In separa te multivariable models of total cholesterol, triglycerides, HDL-cholesterol, systolic blood pressure, abdominal obesity, diabetes and family history of CHD, small dense-LDL and apolipoprotein B were each statistically significantly associated with CHD events (for 1 mg/dl increase: odds ratio [OR] 1.05, 95% CI 1.00-1.11 and 1.15, 95% CI 1.01-1.31, respectively), but the ratiosof small dense-LDLlapolipoprotein A-I (OR 1.26, 95% CI 0.95-1.67), apolipoprotein B/apolipoprotein A-I (OR 1.02, 95% CI 0.97-1.07) and HDL-cholesterol! total cholesterol (OR 0.99 95% CI 0.98-1.00) were not. Following adjustment for HIV related and cART variables these associations were weakened in each model: apolipoprotein B (OR 1.27, 95% CI 1.00-1.30), sd-LDL (OR 1.04, 95% CI 0.99-1.20), small dense-LDLlapolipoprotein A-I (OR 1.17, 95% CI 0.87-1.58), apolipoprotein B/apolipoprotein A-I (OR 1.02, 95% CI 0.97-1.07) and total cholesterolJHDL- cholesterol (OR 0.99, 95% CI 0.99-1.00).Conclusions: In patients receiving cART, small dense-LDL and apolipoprotein B showed the strongest associations with CHD events in models controlling for traditional CHD risk factors including total cholesterol and triglycerides. Adding small dense LDLlapoplipoprotein A-l, apolipoprotein B/apolipoprotein A-I and total cholesterol! HDL-cholesterol ratios did not further improve models of lipid parameters and associations of increased risk for CHD events.

Shorter time to diagnosis and improved stage at presentation in Swiss patients with retinoblastoma treated from 1963 to 2004

Rapport de synthèse : Le rétinoblastome est la tumeur de l'oeil la plus fréquente chez l'enfant. Un diagnostic précoce est important pour sauver le globe oculaire et la survie du patient. Le but de notre étude est de déterminer l'évolution de l'intervalle diagnostique, c'est-à-dire le délai entre les premiers symptômes et la date du diagnostic officiel du rétinoblastome, sur une période de 40 ans en Suisse. Matériel et méthode : Il s'agit d'une étude rétrospective faite sur 139 patients suisses traités pour rétinoblastome durant trois différentes périodes : (1) 1963-1983 ; (2) 1984-1993 ; et (3) 1994-2004. On compare certaines caractéristiques : le sexe du patient, la latéralité de la maladie, les premiers symptômes, leurs observateurs, l'intervalle diagnostique, l'âge au diagnostic, le stade de la maladie, l'histoire familiale. Résultats : 37 patients (26.6%) ont été traités dans la première période ; 44 (31.7%) dans la période 2 et 58 (41.7%) dans la période 3. L'intervalle diagnostique diminue de façon significative de 6.97 mois dans la période 1 à 3.58 dans la période 2 à 2.25 dans la période 3 pour le total des malades. Ceci reste significatif pour les rétinoblastomes unilatéraux. De plus, dans ce même groupe, on observe une diminution significative des stades avancés de la maladie, groupe E selon Murphree (61.5% dans la période 1 ; 46.7% dans la période 2 et 22.2 % dans la période 3). Lorsque la maladie est bilatérale, les mêmes observations se font de façon un peu moins marquée. Il n'y a aucun patient diagnostiqué au stade E de la maladie en présence d'une anamnèse familiale positive. Leucocorie (48.2%) et strabisme (20.1 %) sont les symptômes les plus fréquents durant les 3 périodes. Les seuls facteurs qui influencent significativement le risque d'avoir un stade E de la maladie sont la durée de l'intervalle diagnostic et la période de diagnostic. Conclusion : On constate un progrès dans le diagnostic du rétinoblastome en Suisse, surtout lors de maladie unilatérale. De même, des améliorations sont notées dans la maladie bilatérale mais de façon non significative. Il est donc important de mieux enseigner aux médecins à reconnaître les symptômes oculaires de la maladie et à référer les patients plus tôt aux spécialistes. Abstract : OBECTIVES : Retinoblastoma is the most frequent intraocular malignancy in children. Early diagnosis is essential for globe salvage and patient survival. The aim of our study was to determine how time to diagnosis of retinoblastoma has evolved over a 40-year period in Switzerland. METHOD AND PATIENTS : A retrospective study of 139 Swiss patients with retinoblastoma was performed comparing 3 periods: (1) 1963-1983; (2) 1984-1993; and (3) 1994-2004. Factors taken into account were gender, laterality of retínoblastoma, age at first symptoms, type and first observer of symptoms, time to diagnosis, age at diagnosis, disease stage, and family history. RESULTS : Thirty-seven patients (26.6%) were treated in period 1, 44 (31.7%) in period 2, and S8 (41.7%) in period 3.Overall, the diagnostic interval decreased in a significant way from 6.97 months in period 1 to 3.58 in period 2 and to 2.25 in period 3. When looking separately at unilateral and bilateral disease, the decrease oí the diagnostic interval remained statistically significant in unilateral retinoblastoma; there was also a significant reduction in the number of patients with advanced group E disease (Murphree classification) (61.5% in period 1, 46.7% in period 2, 22.2% in period 3). In bilateral disease, the same observations were made to a lesser extent. However, there were no cases with group E disease in 10 patients with positive family history. Leukornria (48.2%) and strabismus (20.1 %) were the 2 most frequent symptoms throughout the 3 periods. The only factors that statistically influenced the chances of having a diagnosis of group E disease were the diagnostic interval and period of diagnosis. Conclusion : Progress has been made in the diagnosis of retinoblastoma in Switzerland, notably in unilateral disease. Improvement to a lesser extent has also been observed in bilateral cases but without statistical significance. Greater effort is needed to teach physians-in-training to recognize the importance of ocular symptoms and refer patients earlier.

Who is at low risk for cardiovascular disease? An assessment of different definitions

Purpose: To assess the prevalence and trends of low cardiovascular risk factor (RF) profile in the Swiss population according to different definitions. Methods: Population-based cross-sectional study of 6170 subjects (3241 women) aged 35-75 years living in Lausanne, Switzerland. Trends were assessed using data from the Swiss MONICA population surveys conducted in 1984-6 (N=3300), 1988-9 (N=3331) and 1992-3 (N=3133) and restricted to the same age group. Seven different definitions of low RF profile were used. Results: Prevalence of low RF profile varied between 6.5% (95% confidence interval: 5.9-7.1) and 9.7% (9.0-10.5) depending on the definition used. The prevalence was inversely related to the number of criteria used and higher than in other countries. Irrespective of the definition used, the prevalence of low RF profile was higher in women and in physically active participants, and decreased with increasing age or in the presence of a family history of cardiovascular disease (table). The prevalence of low RF profile increased from 3.8% (3.1-4.5) in 1984-6 to 6.7% (6.1-7.3) in 2003-6; using another definition, the results were 5.9% (5.1-6.8) and 9.7% (9.0-10.5), respectively. Conclusion: The prevalence of low RF profile varies according to the criteria used; this prevalence is relatively high and increasing in the Swiss population, which might partly explain the low and decreasing trend in cardiovascular mortality rates.

Perception of tobacco, cannabis, and alcohol use of others is associated with one's own use.

BACKGROUND: Interventions have been developed to reduce overestimations of substance use among others, especially for alcohol and among students. Nevertheless, there is a lack of knowledge on misperceptions of use for substances other than alcohol. We studied the prevalence of misperceptions of use for tobacco, cannabis, and alcohol and whether the perception of tobacco, cannabis, and alcohol use by others is associated with one's own use. METHODS: Participants (n=5216) in a cohort study from a census of 20-year-old men (N=11,819) estimated the prevalence of tobacco and cannabis use among peers of the same age and sex and the percentage of their peers drinking more alcohol than they did. Using the census data, we determined whether participants overestimated, accurately estimated, or underestimated substance use by others. Regression models were used to compare substance use by those who overestimated or underestimated peer substance with those who accurately estimated peer use. Other variables included in the analyses were the presence of close friends with alcohol or other drug problems and family history of substance use. RESULTS: Tobacco use by others was overestimated by 46.1% and accurately estimated by 37.3% of participants. Cannabis use by others was overestimated by 21.8% and accurately estimated by 31.6% of participants. Alcohol use by others was overestimated by more than half (53.4%) of participants and accurately estimated by 31.0%. In multivariable models, compared with participants who accurately estimated tobacco use by others, those who overestimated it reported smoking more cigarettes per week (incidence rate ratio [IRR] [95% CI], 1.17 [range, 1.05, 1.32]). There was no difference in the number of cigarettes smoked per week between those underestimating and those accurately estimating tobacco use by others (IRR [95% CI], 0.99 [range, 0.84, 1.17]). Compared with participants accurately estimating cannabis use by others, those who overestimated it reported more days of cannabis use per month (IRR [95% CI], 1.43 [range, 1.21, 1.70]), whereas those who underestimated it reported fewer days of cannabis use per month (IRR [95% CI], 0.62 [range, 0.23, 0.75]). Compared with participants accurately estimating alcohol use by others, those who overestimated it reported consuming more drinks per week (IRR [95% CI], 1.57 [range, 1.43, 1.72]), whereas those who underestimated it reported consuming fewer drinks per week (IRR [95% CI], 0.41 [range, 0.34, 0.50]). CONCLUSIONS: Perceptions of substance use by others are associated with one's own use. In particular, overestimating use by others is frequent among young men and is associated with one's own greater consumption. This association is independent of the substance use environment, indicating that, even in the case of proximity to a heavy-usage group, perception of use by others may influence one's own use. If preventive interventions are to be based on normative feedback, and their aim is to reduce overestimations of use by others, then the prevalence of overestimation indicates that they may be of benefit to roughly half the population; or, in the case of cannabis, to as few as 20%. Such interventions should take into account differing strengths of association across substances.

Investigating mineralocorticoid hypertension.

About 3% of our hypertensive patients have high blood pressure induced by corticosteroids. Muscle weakness, tiredness, polyuria and polydipsia may indicate hypokalaemia. Hypokalaemic hypertension in the presence of a low plasma renin activity is the typical finding of corticosteroid hypertension. The most frequent cause of corticosteroid hypertension is primary aldosteronism (Conn's syndrome) due to an adrenal adenoma or bilateral hyperplasia of the adrenal glands. The plasma concentration of aldosterone and the ratio between plasma aldosterone and renin concentrations are high, and the kaliuresis exceeds 30 mmol/24 h in the presence of hypokalaemia. Adrenal carcinomas are rare and very malignant. The localization of an adrenal tumour is made by computer tomography (CT-scan) or nuclear magnetic resonance imaging and by measurement of the aldosterone/cortisol concentrations in the adrenal venous blood. Adenomas are removed under laparoscopy, and adrenal hyperplasias are treated with spironolactone (50-400 mg daily) or amiloride (5-30 mg daily). In rare cases (<1%), excessive stimulation of the mineralocorticoid receptor is due to cortisol (apparent mineralocorticoid excess, Cushing's disease, liquorice, or hereditary deficiency of 11beta-hydroxysteroid dehydrogenase) or to a chimeric gene coding for 11beta-hydroxylase (CYP11B1/CYP11B2). In these rare cases, the synthesis of aldosterone is under the control of the adrenocorticotrophic hormone, so treatment with glucocorticoids (dexamethasone 0.25-1.0 mg daily) is therefore possible (glucocorticoid-remediable aldosteronism). Excessive deoxycorticosterone (DOC) causes the same symptoms and signs as hyperaldosteronism. Excessive DOC is found in patients with adrenal tumours that secrete DOC, in those with hereditary or acquired disorders with dysfunctioning glucocorticoid receptors, or in those with congenital hyperplasia of the adrenal glands (deficiency of 17alpha-hydroxylase or 11beta-hydroxylase). Liddle's syndrome is a constitutive hyperactivity of the transepithelial transport of sodium, which under normal conditions is controlled by the mineralocorticoid receptor. Plasma renin and aldosterone concentrations are suppressed and the plasma potassium concentration may be normal. In contrast, plasma aldosterone and renin concentrations are increased in patients with hypokalaemic hypertension which represents secondary aldosteronism. The increased aldosterone is the consequence of stimulated renin activity due to renal or renovascular or other disorders, antihypertensive drugs or other medications. In conclusion, a work-up for corticosteroid-induced hypertension is indicated in patients with hypokalaemic hypertension and in those with severe hypertension even in the absence of hypokalaemia, and in hypertensive patients with a family history of cardiovascular diseases.

Prevalence of left ventricular regional dysfunction in arrhythmogenic right ventricular dysplasia: a tagged MRI study.

BACKGROUND: Although arrhythmogenic right ventricular dysplasia (ARVD) predominantly affects the right ventricle (RV), genetic/molecular and histological changes are biventricular. Regional left ventricular (LV) function has not been systematically studied in ARVD. METHODS AND RESULTS: The study population included 21 patients with suspected ARVD who underwent evaluation with MRI including tagging. Eleven healthy volunteers served as control subjects. Peak systolic regional circumferential strain (Ecc, %) was calculated by harmonic phase from tagged MRI based on the 16-segment model. Patients who met ARVD Task Force criteria were classified as definite ARVD, whereas patients with a positive family history who had 1 additional minor criterion and patients without a family history with 1 major or 2 minor criteria were classified as probable ARVD. Of the 21 ARVD subjects, 11 had definite ARVD and 10 had probable ARVD. Compared with control subjects, probable ARVD patients had similar RV ejection fraction (58.9+/-6.2% versus 53.5+/-7.6%, P=0.20), but definite ARVD patients had significantly reduced RV ejection fraction (58.9+/-6.2% versus 45.2+/-6.0%, P=0.001). LV ejection fraction was similar in all 3 groups. Compared with control subjects, peak systolic Ecc was significantly less negative in 6 of 16 (37.5%) segments in definite ARVD and 3 of 16 segments (18.7%) in probable ARVD (all P<0.05). CONCLUSIONS: ARVD is associated with regional LV dysfunction, which appears to parallel degree of RV dysfunction. Further large studies are needed to validate this finding and to better define implications of subclinical segmental LV dysfunction.