Aida Kirschbaum

Impact of parity on anthropometric measures of obesity controlling by multiple confounders: a cross-sectional study in Chilean women

Aim: To find out whether there is an association between parity and obesity, evaluated through body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR) in Chilean women after controlling for sociodemographic characteristics, health risk and gynaeco-obstetric factors. Design: Cross-sectional study, using baseline data of the San Francisco Project. Setting: San Francisco de Mostazal, located in the central region of Chile, 6512 Chilean-Hispanic women (Spanish heritage with a variable indigenous component). Methods: A weighted random sample of 508 women who had their first pregnancy inside the primary child-bearing ages. Data were collected between 1997 and 1999. Statistical associations between parity and different anthropometric measurements of adiposity in multiple linear (MLnR) and logistic regression models (MLtR) were evaluated. Results: In MLnR a modest parity-related increment in BMI and practically null increment in WC, WHR and WHtR was observed. Covariates that showed a statistically significant association with anthropometric measures of adiposity were age, low education, marital status, employment, smoking, smoking cessation, hypertension, diabetes, dyslipidaemia, parent’s obesity, menarche and fetal macrosomia. Crude odds ratio (OR) showed a strong association between parity and anthropometric markers of obesity. Nevertheless, after adjustments in MLtR models, the association remained only for BMI. All the measures of abdominal obesity related to parous women showed OR smaller than 1 (95% confidence intervals 0.57 to 0.96). Conclusions: Parity modestly influences BMI, but does not seem to be related to WC, WHR and WHtR after controlling by confounders. Parity can increase adiposity but not necessarily following an abdominal pattern.

A landmark for popperian epidemiology: refutation of the randomised Aldactone evaluation study

In 1999 a great multi-site clinical trial known as the randomised Aldactone evaluation study (RALES) showed that the use of spironolactone importantly reduced complications attributable to chronic heart failure without major negative side effects. Recently, RALES has been questioned by a large scale observational study in the Ontario population. In contrast with predictions, the complications and mortality increased dramatically because of hyperkalaemia, reaching dimensions that from a public health perspective are comparable to an epidemic. This review analyses both researches in the light of Karl Popper’s science theory applying the modus tollens syllogism to the reality proposed by the main empirical enunciations that ensue from its epidemiological designs. RALES is deductively refuted because of the non-fulfillment of auxiliary assumptions that would act as reciprocal potential falsifiers in both studies, taking the logical form of a bi-conditional argument of the type: (a) P-then-Q and (b) Q-if-XP, XP being a set of potential falsifiers of Q as part of the explicit falsity content of P. From this popperian model, implications for clinical research are discussed.

Desigualdad educacional y socioeconómica como determinante de mortalidad en Chile: análisis de sobrevida en la cohorte del proyecto San Francisco

In thisprospective cohort study, a random sample of 920 subjects, living in San Francisco de Mostazal, Chile,aged more than 20 years (395 males) was examined for the first time in 1997-1999 and re-examinedin 2005-2006. All had information about economic household income and level of education. A Coxregression model was used to evaluate the association between mortality and socioeconomic measures.