Reading for the comparison itself: Why Does My AHI Change Night to Night? Normal Variation Explained — what is noise and what is a trend. Why Is My AHI High on CPAP? Causes and How to Find Yours — when the number really has moved, and the usual reasons. CPAP 95th-Percentile vs Median Pressure: What the Numbers Mean — the pressure figure that is worth comparing across months. Nothing on SomniTalk is medical advice. Talk to your own clinician before changing therapy.