Vision Worsening

[rodan]

I was diagnosed with open angle glaucoma four years ago. I'm nearsighted(have been since I was 16, I'm now 55 years old)and it's gotten worse this past year.  I had been 20/400 in both eyes for about 35 years, and my IOP averaged 17 to 20 during those years.  
Four years ago, during a time I was under heavy stress, I woke up one morning and noticed some vision loss in right eye.  Then it happened again six months later.  It was then I noticed I didn't see very well at night from then on.
Went to doctor and my IOP numbers were 28 so he put me on Xalatan.  Vision field test  showed I lost about half vision in my right eye.  He attributed my vision loss to glaucoma.  Also, to rule it out, I got tested for diabetes, and had nomal blood sugar levels ( 74 ).  My prescription also went from 20/400 to 20/600 in both eyes.
Two years later, doc put me on two more medications, ( Cosopt and Alphagan ) as my IOP was increasing.
About a year ago, I noticed my nearsightness worsening, eye check showed my vision 20/800 left eye and 20.700 in right eye.   Six months later, I'm now
20/850 left eye and 20/700 right.   Even with  the corrected lenses, I really don't see 20/20, more like 20/40.  
On suggestion from doctor, I again checked for diabetes, (and it was nomal , 76 )
as he said diabetes can cause a person's eyes to loose visual acuity.
My two questions:  Can glaucoma cause nearsightness to worsen as in my case?  With the medications, it keeps my IOP at about 18 in each eye.   I was a bit overweight and lost 30 lbs, and watch what type of foods I eat, ( avoided refined carbs and sugar ed foods).
Is it possible the combinations of glaucoma medications can worsen myopia, visual acuity?

[John C Hagan III, MD, FACS]

Glaucoma does not cause increasing myopia but developing cataracts do ("second sight") It is far more likely you have cataracts causing this.

Glaucoma medications do not cause increasing myopia nor loss of visual acuity. However glaucoma, cataracts, diabetes and macular degeneration due to age are possible causes of your problem.

JCH III MD Eye Physician & Surgeon