What is the next best step for an elderly male patient with type 2 diabetes, taking metformin (1000 mg daily), Januvia (sitagliptin), and Lantus (insulin glargine), with morning fasting blood sugars of 150-200 mg/dL, and a history of recurrent fungal infections, who cannot continue Farxiga (dapagliflozin)?

Increase Lantus (Insulin Glargine) Dose

The next best step is to titrate up the Lantus dose to target fasting blood glucose of 90-130 mg/dL, increasing by 2 units if ≥50% of fasting values remain above goal. 1

Rationale for Lantus Titration

The patient's fasting blood sugars of 150-200 mg/dL indicate inadequate basal insulin coverage, which is the primary driver of morning hyperglycemia. Since he is already on metformin, Januvia (sitagliptin), and Lantus, the most direct and evidence-based approach is to optimize the existing basal insulin regimen before adding complexity. 2, 1

Key Titration Parameters:

• Increase Lantus by 2 units if ≥50% of fasting glucose values are above target (90-130 mg/dL) 1
• Decrease by 2 units if >2 fasting values per week are <80 mg/dL 1
• Monitor fasting glucose daily during titration phase 1
• Reassess weekly until fasting glucose consistently reaches 90-130 mg/dL 1

Why Not Other Options?

Increasing Metformin Dose

The patient is only on metformin 1000 mg daily, which could theoretically be increased to 2000 mg daily. However, metformin primarily addresses postprandial glucose and hepatic glucose production throughout the day, not specifically fasting hyperglycemia. 2 Given his elevated fasting values, optimizing basal insulin is more targeted and effective.

Adding Another Oral Agent

While DPP-4 inhibitors like Januvia are safe in the elderly with low hypoglycemia risk 2, he is already on Januvia. Adding additional oral agents when basal insulin is suboptimally dosed would be premature and add unnecessary medication burden. 2

Switching to Premixed Insulin (70/30)

Premixed insulins should generally be avoided in elderly patients due to a threefold higher rate of hypoglycemia compared to basal-bolus regimens with analogs. 2 The fixed ratio offers less flexibility and increases hypoglycemia risk, particularly problematic in the elderly. 3

Elderly-Specific Considerations

Glycemic Targets

For this elderly patient, the American Geriatrics Society recommends individualizing HbA1c targets based on health status. 2 If he is relatively healthy with intact cognitive function, target HbA1c <7.5%; if he has multiple comorbidities or frailty, a less stringent target of 8.0-8.5% is appropriate. 2 However, fasting glucose of 150-200 mg/dL likely corresponds to HbA1c well above these targets and warrants intervention.

Hypoglycemia Prevention

• Morning administration of Lantus rather than bedtime dosing reduces nocturnal hypoglycemia risk in elderly patients 1
• Conservative titration (2 units at a time) minimizes hypoglycemia risk 1
• Patient/caregiver education on recognizing and treating hypoglycemia is essential 1
• The American Diabetes Association emphasizes that older adults on insulin require careful monitoring for hypoglycemia, which can cause cognitive impairment, falls, and cardiovascular events 2

Monitoring Strategy

Blood Glucose Testing

• Check fasting glucose daily during dose titration 1
• Test before meals and bedtime if adding prandial insulin later 3
• Test when suspecting hypoglycemia (symptoms include confusion, tremor, sweating) 3

HbA1c Monitoring

• Recheck HbA1c every 3-6 months until stable at goal 2
• Once stable, can extend to every 12 months 2

Common Pitfalls to Avoid

1. Do not use sliding scale insulin alone in outpatient elderly patients—it is ineffective and increases hypoglycemia risk 2

2. Do not administer Lantus at bedtime initially in elderly patients due to increased nocturnal hypoglycemia risk; morning dosing is preferred 1

3. Do not use aggressive titration (>2 units per adjustment) in older adults 1

4. Do not ignore renal function when using metformin—check eGFR and avoid if <30 mL/min/1.73 m², use lower doses if 30-60 mL/min/1.73 m² 2

5. Avoid glyburide if considering sulfonylureas due to high hypoglycemia risk in elderly 2

When to Consider Alternative Strategies

If fasting glucose remains uncontrolled after optimizing Lantus to 0.3-0.4 units/kg/day (typically 20-30 units for most patients), consider:

• Adding GLP-1 receptor agonist (if tolerated and no contraindications) for additional glucose lowering with low hypoglycemia risk 2, 3
• Basal-bolus regimen with rapid-acting insulin at meals, though this increases complexity and hypoglycemia risk 2
• Referral to endocrinology for complex cases or frequent hypoglycemia 2

Note on Farxiga Discontinuation

The patient's history of recurrent fungal infections with Farxiga (dapagliflozin) is appropriate grounds for discontinuation, as SGLT2 inhibitors increase risk of genital mycotic infections, particularly in patients with prior history. 4 This reinforces that optimizing existing insulin therapy is the correct path forward rather than attempting another SGLT2 inhibitor.