Obesity in older adults: When to treat with medications

Abstract

The prevalence of obesity in older adults (≥ 60 years) has reached critical levels of 42%, representing a public health challenge due to its association with disability, mortality, and frailty. With aging, body composition changes, increasing visceral adiposity and decreasing muscle mass, which gives rise to a phenotype with higher cardiometabolic risk known as sarcopenic obesity. Clinical management must transcend chronological age, prioritizing the patient's functional status and biological health.

Evaluation must be comprehensive, analyzing comorbidities, frailty using validated scales (Fried, Edmonton), and anthropometric assessment. It is essential to diagnose sarcopenic obesity by measuring muscle strength (handgrip or chair-stand test) and quantifying lean mass (DXA or BIA).

Treatment indications are the same as for the general population, but taking certain precautions into account. According to ADA standards, pharmacological treatment is indicated with a BMI ≥ 30 kg/m² or ≥ 27 kg/m² in the presence of complications such as prediabetes, type 2 diabetes, hypertension, established cardiovascular disease, heart failure with preserved ejection fraction, steatohepatitis, sleep apnea, or osteoarthritis.

Although older adults are often underrepresented in clinical trials, evidence from pivotal studies on the efficacy of drugs in weight loss is overwhelming:

• Orlistat (XENDOS): 3-5% weight loss; requires monitoring hydration and supplementing fat-soluble vitamins to protect bone and muscle health.
• Naltrexone/Bupropion (COR): 5% weight loss; useful in emotional eating, but requires caution due to the risk of neuropsychiatric effects such as agitation and insomnia.
• Liraglutide (SCALE/LEADER): 8% weight loss and a 34% reduction in MACE in individuals ≥ 75 years.
• Semaglutide (STEP/SELECT): 16% weight loss and a 20% reduction in MACE.
• Tirzepatide (SURMOUNT/SUMMIT): 21% weight loss and a 38% reduction in heart failure events.

Precautions include: evaluating interactions due to polypharmacy, gradual titration, optimal hydration, and a protein intake of 1.2 to 1.5 g/kg/day along with individualized strength exercises to preserve muscle mass and autonomy.

Advanced age is not a contraindication for pharmacotherapy. Cardiometabolic benefits are evident as long as continuous evaluation of adverse effects is performed. However, long-term studies specifically targeting the older adult population are required. The goal of treatment is not only to lose weight but to improve functionality and quality of life.