Prevalence of normal weight obesity in Switzerland: effects of various definitions

Background: normal weight obesity (NWO) is defined as an excessive body fat associated with a normal body mass index (BMI<25 kg/m2), but its prevalence in the general population is unknown. Objective: to assess the prevalence of NWO in Switzerland according to different cut points used to define excess body fat. Design: cross-sectional study including 3,213 women and 2,912 men aged 35-75 years. Body fat was assessed by bioimpedance and prevalence of NWO was assessed using four previously published definitions for excess body fat. Results: % body fat increased with age: in men, the values (mean SD) were 20.2 5.4, 23.0 5.4, 26.3 5.2 and 28.2 4.6 for age groups [35 - 44], [45 - 54], [55 - 64] and [65 - 75] years, respectively; the corresponding values for women were 29.9 7.8, 33.1 7.4, 36.7 7.5 and 39.6 6.9. In men, prevalence of NWO was <1% irrespective of the definition used. Conversely, in women, a one to twenty fold difference (from 1.4% to 27.8%) in NWO prevalence was found. The prevalence of NWO increased with age when age-independent cut points were used in women, but not in men. Conclusions: prevalence of NWO is low in the general population and higher in women than in men. The prevalence is highly dependent on the criteria used to define excess body fat, namely in women. The use of gender- and age-specific cut points to define excess body fat is better than fixed or gender-specific only cut points.

Adiponectin and C-reactive protein are positively associated with microalbuminuria in an adult Caucasian population

Objective: Microalbuminuria (MAU) is a marker of early kidney injury and cardiovascular risk. We assessed the association of MAU with plasma adiponectin, leptin, and hsCRP as inflammatory marker, accounting for hypertension, diabetes and obesity. Design and Methods: Population based, cross-sectional study in Caucasian subjects aged 35 to 75 years in Lausanne, Switzerland. MAU, measured by quantitative immunonephelometry on spot morning urine, was used either as a continuous (MAU) or dichotomized variable (MA defined as MAU > 2.5 and >3.5 mg/mmol creatinine in men and women, respectively). Results: The 2955 women (age 53.3_10.7, mean_SD years) had mean body mass index (BMI) 24.9_4.5 kg/m. The 2479 men (age 53.1_10.8 years) hadmean BMI 27.0_3.9 kg/m2.Median hsCRP was 1.3 and 1.3 mg/L, median adiponectin 6.2 and 10.6mg/mL in men and women, respectively. MA prevalence was 4.9% in women and 9.8% in men. In multivariate regression analysis adjusting for potential confounders (age, sex, hypertension, diabetes, eGFR, BMI, percent fat mass, insulin and smoking), logtransformed MAU was positively associated with hsCRP (P<0.001) and adiponectin (P¼0.002), but not with leptin. The association of adiponectin with MAU was stronger in subjects with low hsCRP, and vice versa (P interaction<0.001). Conclusion: Adiponectin and hsCRP are significant positive determinants of MAU, independently of diabetes, hypertension and fat mass. A negative interaction between hsCRP and adiponectin was found for their effect on MAU. Whether hyperadiponectinemia represents an adequate protective response to vascular stress or has negative causal impact on the development of MAU should be assessed in further studies.

Laboratory-based versus non-laboratory-based CVD risk analysis.

Commentaire de: Gaziano TA, Young CR, Fitzmaurice G, Atwood S, Gaziano JM. Laboratory-based versus non-laboratory-based method for assessment of cardiovascular disease risk: the NHANES I Follow-up Study cohort. Lancet. 2008;371(9616):923-31. PMID: 18342687

SIMULIT : un modèle de simulation pour l'analyse et la planification de l'activité hospitalière

Le modèle développé à l'Institut universitaire de médecine sociale et préventive de Lausanne utilise un programme informatique pour simuler les mouvements d'entrées et de sorties des hôpitaux de soins généraux. Cette simulation se fonde sur les données récoltées de routine dans les hôpitaux; elle tient notamment compte de certaines variations journalières et saisonnières, du nombre d'entrées, ainsi que du "Case-Mix" de l'hôpital, c'est-à-dire de la répartition des cas selon les groupes cliniques et l'âge des patients.

Prevalence of normal weight obesity in the general population

Background and Aims: normal weight obesity (NWO) has been defined as an excessive body fat (BF) associated with a normal body mass index (BMI). Little is known regarding its prevalence in the general population or which cut-offs for BF should be used. Methods: convenience sample of 1,523 Portuguese adults. BF was measured by validated hand-held bioimpedance. NWO was defined as a BMI<25 kg/m2 and a %BF mass>30%, along other published criteria. Results: prevalence of NWO was 10.1% in women and 3.2% in men. In women, prevalence of NWO increased considerably with age, and virtually all women aged over 55 with a BMI<25 kg/m2 were actually considered as NWO. Using gender specific cut-offs for BF (29.1% in men and 37.2% in women) led to moderately lower of NWO in women. Using gender- and age-specific cut-points for %BF considerably decreased the prevalence of NWO in women (0.5 to 2.5% depending on the criterion) but not in men (1.9 to 3.4%). Conclusions: gender- and age- specific or at least gender-specific, instead of single cut-offs for %BF, should be used to characterize and study NWO.

Sondage pilote concernant la fréquentation d'une unité mobile de mammographie

En matière de dépistage du cancer du sein, il a été proposé de compléter les moyens techniques actuellement disponibles des praticiens du canton de Vaud par ceux d'une unité mobile de mammographie. Avant de se lancer dans cette aventure, il paraît raisonnable d'estimer le volume et la nature de la demande pour ce nouveau service. La participation des femmes vaudoises peut être évaluée par une enquête de population. Pour préparer cette enquête, un sondage téléphonique pilote a été effectué, permettant d'en estimer la faisabilité, le coût et le rendement.

La prévention est un sport de combat. [Prevention is a combat sport].

Fred Paccaud, professeur d'épidémiologie et de santé publique (Lausanne), réagit à la campagne de dénigrement menée en avril 2008 contre le directeur de l'Office fédéral de la santé publique et les campagnes de prévention.