A 32-year-old male with schizoaffective disorder has been taking olanzapine 20 mg daily for two years with excellent psychiatric stability. He has gained 45 pounds since starting the medication, with his BMI increasing from 26 to 33. His fasting glucose is 112 mg/dL, triglycerides are 220 mg/dL, and HDL is 34 mg/dL. The PMHNP previously implemented a structured lifestyle intervention including dietary counseling and an exercise referral six months ago. At this visit, he reports he has been unable to sustain the lifestyle changes due to persistent sedation, increased appetite, and lack of motivation. His weight has increased by an additional 8 pounds in the past six months despite the intervention. The PMHNP is evaluating the metabolic management strategy. Which evaluation is most clinically appropriate?