HRT effects on inflammatory markers: is chronic inflammation a contra-indication for HRT?

C-reactive protein is linked to lower cognitive performance in overweight and obese women

Our objective was to ascertain the nature of the associations between C-reactive protein (CRP) and cognition, and to examine how they are affected by gender and obesity. We evaluated 62 females and 63 males between 42 and 82 years of age. There were 20 lean females with a body mass index (BMI) of <25 kg/m2 and 42 overweight or obese females, with BMIs > or =25 kg/m2. There were 14 lean males and 49 with BMIs >/=25 kg/m2. CRP was associated with lower scores on cognitive tests of frontal lobe function among females and these associations were driven by the overweight/obese female group. In these data no associations between CRP and cognition were found among males. Obesity-associated inflammation is much more prominent in females and it appears to be associated with cognitive dysfunction, particularly of frontal lobe tasks.

Principles of use of surrogate markers and endpoints

Surrogate end-points are markers of biological mechanisms and require a mechanistic view on diseases. Thus, the validation of candidate surrogate end-points for the cardiovascular risk of sex steroids requires that a separate evaluation be made of the various clinical endpoints in which different biological mechanisms are likely to operate. The case of venous thromboembolic (VTE) disease and arterial diseases is complex since they are multifactorial and multiple surrogate end-points are likely to be relevant. In addition sex steroids have many effects on biological mechanisms and the selection and validation of surrogates from the available bulk of changes in multiple mechanisms is a large enterprise. In addition, the combination of candidates in algorithms is required and at very early development stages only. In practice, the validation of candidates requires the detection of changes or levels achieved in intervention trials with clinical end-points and such evaluations are scarce. The observations of increased risk of VTE for first-time users of sex steroids indicate the occurrence of a susceptible subgroup, suggesting that effects in this group may be dissimilar to those in the population as a whole or quantitatively strongly different.