For a 70-year-old woman with hypertension (HTN), hypothyroidism, and morbid obesity, which is more effective and affordable to prescribe, tirzepatide or semaglutide?

Tirzepatide Is Superior to Semaglutide for Weight Loss in a 70-Year-Old Woman with HTN, Hypothyroidism, and Morbid Obesity, Though Semaglutide May Be More Affordable

For a 70-year-old woman with hypertension, hypothyroidism, and morbid obesity, tirzepatide is recommended over semaglutide due to superior weight loss efficacy, though semaglutide may be more affordable depending on insurance coverage.

Efficacy Comparison

• Tirzepatide demonstrates significantly greater weight loss compared to semaglutide in direct comparison studies, with tirzepatide showing 20.2% weight reduction versus 13.7% with semaglutide at 72 weeks 1
• Tirzepatide's dual-receptor action (GLP-1 and GIP) provides enhanced metabolic benefits compared to semaglutide's single GLP-1 receptor action 2
• In real-world studies, tirzepatide resulted in 16.5% weight loss compared to 14.1% with semaglutide after one year of treatment 3
• For patients with obesity, tirzepatide 15mg weekly was associated with greater weight loss (20.9%) compared to semaglutide 2.4mg weekly (14.9%) 2

Cardiovascular Benefits (Important for HTN)

• GLP-1 receptor agonists like semaglutide have demonstrated cardiovascular benefits in patients with pre-existing cardiovascular disease who are overweight/obese 4
• The SELECT study showed semaglutide 2.4mg reduced the composite incidence of cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke (HR 0.80) in patients with cardiovascular disease and BMI ≥27 2
• Both medications have beneficial effects on blood pressure, which is particularly relevant for this patient with hypertension 2

Considerations for Hypothyroidism

• Both medications are generally safe for patients with hypothyroidism, though monitoring of thyroid function is recommended 4
• GLP-1 receptors are expressed in the thyroid, which may explain some of the pleiotropic effects of these medications 4

Safety Profile and Side Effects

• Both medications have similar adverse effect profiles, with gastrointestinal effects predominating (nausea, vomiting, diarrhea, constipation) 2
• Gradual dose titration is recommended for both medications to minimize gastrointestinal side effects 4
• Both medications are contraindicated in patients with personal or family history of medullary thyroid cancer or multiple endocrine neoplasia syndrome type 2 2, 5
• Both medications have minimal risk for hypoglycemia when used as monotherapy 2, 5

Cost Considerations

• Semaglutide may be more affordable than tirzepatide depending on insurance coverage 6
• A value analysis showed the cost needed to treat per 1% of body weight reduction was $985 for tirzepatide compared to $1,845 for semaglutide, suggesting tirzepatide provides better value for money despite potentially higher upfront costs 6
• Insurance authorization may be challenging for both medications, particularly for obesity management without diabetes 4

Administration and Dosing

• Both medications are administered as subcutaneous injections once weekly 2
• Tirzepatide is started at 2.5mg weekly and titrated up to a maximum of 15mg weekly 2
• Semaglutide for obesity is started at 0.25mg weekly and titrated up to 2.4mg weekly 4
• Slow titration helps mitigate gastrointestinal side effects for both medications 4

Practical Recommendations for This Patient

• Start with tirzepatide due to superior weight loss efficacy, which is particularly important for morbid obesity 1
• Begin with 2.5mg weekly and gradually titrate up based on tolerability, aiming for the maximum dose of 15mg weekly for optimal weight loss 2
• If cost is prohibitive or insurance denies coverage, switch to semaglutide which still offers significant weight loss benefits 4, 3
• Monitor blood pressure closely as weight loss progresses, as antihypertensive medication requirements may decrease 4
• Ensure thyroid function is optimized before starting treatment and monitor during therapy 4
• Combine medication with lifestyle modifications including reduced-calorie diet and increased physical activity for optimal results 4

Monitoring and Follow-up

• Monitor for gastrointestinal side effects, particularly during dose escalation 4
• Assess weight loss response at regular intervals 2
• Monitor blood pressure and potentially adjust antihypertensive medications as weight decreases 4
• Watch for potential interactions with levothyroxine, though significant interactions are not expected 5
• Be vigilant for signs of gallbladder disease or pancreatitis, which are rare but reported adverse effects 4