A 63-year-old female presents in 2024 with an 8-year history of osteoporosis.  Her first DEXA scan in 2016 revealed a lumbar spine T score of -2.9 which is osteoporotic.  The left total hip T score was -1.1 which is osteopenic.  A follow-up DEXA in 2020 revealed worsening in lumbar spine to a T score of -3.5 which is a 9.2% further bone mineral density (BMD) loss. 

Treatment with Prolia began at that point.  Follow-up DEXA in 2023 showed a 7.6% improvement in the lumbar BMD.

Question: What percentage of loss of BMD does a T score of -3.5 suggest and is a +7.6% treatment response with Prolia enough to prevent fragility fracture risk?