Yes I have had anaemia, or more specifically iron deficiency, alongside my GERD. I already had poor iron stores before I got the acid reflux but then became very anaemic after 2 years of taking a PPI. I had to have a colonoscopy to rule out other causes of the anaemia but that didn't show any cause, nor did my endoscopy. I have since changed to Zantac and my iron deficiency seems to have slowed down quite a lot. In my case the cause seems to be several things in combination - already had low stores, PPI blocks absorption of iron, chronic skin problem (eczema), food allergies and er, ahem, the usual monthly losses (I'm also headed for menopause).
I had noticeable tinnitus and was freezing cold all the time, sore tongue, no energy and shortness of breath going upstairs or hills - also had leg muscle pain on walking up an incline. All that resolved with iron replenishment.
Like you I was very worried about what else they were going to uncover and I got very stressed, especially as I have endoscopy-phobia! However, everything came back ok and now they seem quite disinterested and just top me up with iron infusion from time to time!
Hope that helps........
GERD (3 years and counting)
Lifelong stuff: Food allergies/intolerance, eczema, asthma