Do acid reducing medicines cause dementia?

Recent press coverage suggested that proton-pump inhibitors can cause dementia.  Unfortunately, press coverage seems to have overstated this a bit.

Proton-pump inhibitors (PPI's) are a specific type of acid reducing medication used to treat a variety of conditions such as acid reflux, esophagitis and ulcers.  They include a number of prescription and over-the-counter medications such as Prilosec, Prevacid, Protonix, Nexium and Dexilant.

Basically, an article printed in April in the Journal of the Amercan Medical Association (JAMA) described a German study showing a correlation between PPI use and dementia.

Thing is, correlation is not causation.  This study did not define particular types of dementia, such as Alzheimer's, Parkinson's, Lewy body, vascular or senile dementias.  Also, it did not take into account risks such smoking or drinking.  Both of these would cause stomach problems and are common causes of being on PPI's, and both are by themselves associated with Alzheimer's disease risk.

In other words, a limited study with a number of significant weaknesses reports that many patients with various forms of dementia have taken PPI's.  It in no way establishes that PPI use causes dementia. 

Other acid reducers, called the H2 blockers include Tagamet, Zantac and Pepcid.  These, so far, have not had any  harm from long-term use associated with them.

Generally, it makes sense to use PPI's for very specific conditions such as treatment of Barrett's esophagitis or ulcer prevention with anti-inflammatory pain (NSAID) medication use and to otherwise use H2 blockers or non-medication related supportive care (such as not smoking, and modest alcohol consumption).