Nasal Pillow provides lower AHI vs. Nasal Mask--any truth?

Last night was my first full night on a nasal pillow (Swift FX).
I recently switched from the PRS1 to S9 Autoset (I like both of them -- see my review viewtopic/t77112/viewtopic.php?f=1&t=76 ... ew#p699669), and now I am trying to switch from a nasal mask (Mirage FX) to the nasal pillow Swift FX.

Surprisingly, last night, my first full night on a nasal pillow, my AHI was significantly better than any other night since I started cpap around 1.5 years ago!
Recently AHI has been running around 2, with Central AI around 1.
But last night was the first time ever the AHI was below 1 (it was 0.6, see below).
Is it known, or does anyone else have experience, that using pillows vs nasal mask can help lower AHI?
Of course I will experiment further to make sure this is not a fluke...but it seems like to much of a coincidence to me...

Here's the figures from last night, last week, last month (pressure unchanged at 6 cm H20):
LAST NITE, first full night on nasal pillow:
Leak: 9.6 L/min
AHI 0.6
Total AI 0.6
Central AI 0.4

Last week
Leak: 4.8L/min
AHI 1.7
Total AI 1.3
Central AI 1.0

Last month
Leak: 4.8L/min
AHI 2.2
Total AI 1.7
Central AI 1.1

Any comments, theories appreciated.
Thanks,
Jason

I don't believe it is the mask itself that gives you a lower AHI, but the fact that ANY mask which prevents/lowers leaks will give you a lower AHI. Did you compare your leak rate between the nasal and pillows?

IMHO it doesn't make a difference which mask anyone uses - it's what works for YOU (and them).

Cheers,
xena

Xenablue -- actually the leak rate was higher on the nasal pillow vs. the nasal mask (see above)...but I believe my leak rates have always been within an acceptable range.
This lower AHI after 1.5 years on cpap coinciding with the first all night use of a nasal pillow is just so much of a coincidence -- so I was just wondering if there are any theories out there about nasal pillows resulting in lower AHI...
Thanks,
Jason

No difference...its what works best for YOU. Some will tell you a ffm is best and has lower ahi for them, but that may not be true for you.

Nan is right.
I thought full faces were giving me higher pressures, but when I got the fit right, it's about the same.