Potential weakness of the metanalysis

Luis Carlos Saiz, Pharmacotherapy Research Coordinator,
November 07, 2013

Dear Editor,

I have read with interest your metanalysis on effects of antihypertensive treatment in patients over 65 years of age, and I would like to point to an issue quite relevant on my view. I have checked some of the trials included because I doubted if it was possible to the authors to separate participants with more than 65 years from younger, excluding the latter from the analysis. For instance, in the ALLHAT study the authors have been able to give data from participants older than 65 years because the original paper offers that information. But looking now at the INVEST trial, the bigger of this metanalysis excluding ALLHAT, the authors have included all the 22576 participants. The design of INVEST included people older than 50 years and the report explains that most of them (15053) are under 70 years, so we can expect to have many of them under 65 years. This situation can easily have influence in the outcomes mesured and it should have been managed properly. If we are going to speak about older people, just data from older people should have been collected. Or, if it were not possible to get separate data from some trials, I think it would have been better to exclude them.

Conflict of Interest:

None declared

Conflict of Interest

None declared