From the Guidelines
Elderly individuals may exhibit an ammonia-like odor due to impaired renal function, which leads to a buildup of urea in the body, breaking down into ammonia, and this can be a sign of dehydration or other underlying medical conditions. As people age, their kidneys become less efficient at filtering waste products from the blood, including urea, as noted in the context of assessing hydration status in older adults 1. This odor is often caused by a combination of factors, including decreased kidney function, which can lead to an accumulation of urea, and decreased liver function, contributing to the buildup of ammonia in the body.
To address this issue, several strategies can be employed:
- Maintain proper hydration by drinking enough water, as dehydration can exacerbate the condition, and using tools like the osmolarity equation (osmolarity = 1.86 (Na+ + K+) + 1.15 glucose + urea + 14) to screen for low-intake dehydration in older persons, with an action threshold of >295 mmol/L 1.
- Follow a balanced diet, considering that protein intake can impact urea production, although specific dietary recommendations for reducing ammonia-like odor are not provided in the guideline 1.
- Practice good personal hygiene, including regular bathing and changing clothes, to reduce body odors.
- Consult a doctor if the smell persists, as it may indicate underlying health issues like kidney or liver problems, and periodic assessment of serum osmolality can help identify older adults in need of more intensive support or intervention 1.
It is essential to note that simple signs and tests commonly used to assess low-intake dehydration, such as skin turgor, mouth dryness, weight change, urine color, or specific gravity, should not be used to assess hydration status in older adults, as they are not diagnostically accurate 1. Instead, directly measured serum osmolality or the osmolarity equation can provide more accurate assessments.
From the Research
Possible Causes of Ammonia-Like Odor in Elderly Individuals
- Impaired renal function: There is no direct evidence in the provided studies to support this claim 2, 3, 4, 5, 6.
- Underlying medical conditions:
- Liver cirrhosis: Breath and blood ammonia levels were found to be higher in cirrhotic patients, especially those with hyperammonemia, suggesting a possible link between liver disease and ammonia-like odor 6.
- Hepatic encephalopathy: Fetor hepaticus, a characteristic breath odor, is associated with hepatic encephalopathy, which can cause hyperammonemia 6.
- Other conditions: Halitosis in older adults can be caused by various factors, including gingivitis, periodontal disease, diabetic acidosis, hepatic failure, or respiratory infection, which may contribute to an ammonia-like odor 5.
Relationship Between Ammonia Levels and Odor
- Hyperammonemia: High blood ammonia levels can cause dysfunction of multiple organs and are associated with hepatic encephalopathy, which may lead to an ammonia-like odor 2, 6.
- Breath ammonia measurement: This may be a useful tool in diagnosing and monitoring hepatic encephalopathy, as breath ammonia levels correlate positively with blood ammonia levels 6.