Understanding the Repetitive Saliva Swallowing Test (RSST)
The Standard for Measuring Swallowing Frequency
When trying to quantify the normal rate of swallowing, especially for dry swallows, one of the most reliable methods is the Repetitive Saliva Swallowing Test (RSST). This test measures the number of times a person can voluntarily swallow their saliva within a 30-second period. Unlike swallowing food or liquids, which introduces variables like bolus size and texture, the RSST provides a consistent, objective measure of swallowing function. Recent studies have established age-specific benchmarks using this test, providing clearer guidance than older, less specific research.
For those in their 60s, the average benchmark is approximately 6.7 swallows in 30 seconds. This figure represents a natural decline from the average of 8.5 swallows expected in people in their 20s and 30s. This reduction in speed is a normal, healthy part of aging and is often caused by subtle changes in muscle strength and coordination, not a medical problem. Understanding this benchmark is the first step in differentiating a typical age-related change, known as presbyphagia, from an actual swallowing disorder, or dysphagia.
Normal Age-Related Swallowing Changes
Healthy aging involves a number of physiological and anatomical changes that affect the swallowing process, a condition known as presbyphagia. These are not inherently pathological but can make individuals more vulnerable to dysphagia if other health issues arise.
Some of the most common changes include:
- Muscle Atrophy: The muscles in the mouth, tongue, and throat naturally lose mass and strength over time. This can reduce the force available to propel food and liquid through the pharynx and esophagus.
- Slower Coordination: The precise timing required for swallowing, which involves multiple muscles and nerve groups, becomes slightly less efficient with age. This can result in a longer swallow response time.
- Delayed Swallow Initiation: It is normal for the pharyngeal swallow to be initiated more slowly in older adults. The bolus of food or liquid may reach the throat before the swallow is fully triggered, but in healthy individuals, protective mechanisms prevent aspiration.
- Reduced Sensation: Taste and smell acuity often decline with age, which can affect appetite and the enjoyment of food. This sensory reduction, along with decreased oral moisture, can influence the swallowing process.
How to Differentiate Normal Aging from Dysphagia
While some changes are a natural part of aging, certain symptoms should prompt a consultation with a healthcare provider. Differentiating between normal aging and a swallowing disorder like dysphagia is crucial for early intervention and management. Speech-language pathologists (SLPs) are experts in evaluating and treating swallowing problems.
Normal vs. Dysphagia-Related Swallowing Issues
| Feature | Normal Age-Related Change (Presbyphagia) | Dysphagia (Swallowing Disorder) |
|---|---|---|
| Swallowing Speed | Slower than in younger adults, with longer swallow reaction times. | Marked difficulty swallowing, requiring significant effort or time. |
| Penetration | Occasional, shallow laryngeal penetration (liquid entering the airway) that is spontaneously and effectively cleared. | Frequent or deep penetration that reaches the vocal cords, or aspiration (entering the lungs) that is not cleared. |
| Coughing/Choking | Infrequent coughing while eating or drinking. | Consistent coughing, choking, or throat clearing during or after meals. |
| Bolus Transit | Mild delays in moving food or liquid from the mouth to the esophagus. | Significant residue in the mouth or throat after swallowing, poor bolus clearance. |
| Associated Symptoms | Often no other symptoms are present, and the individual has a functional swallow. | Unexplained weight loss, dehydration, recurrent pneumonia, or a “gurgly” voice after swallowing. |
Strategies to Maintain Healthy Swallowing
For those in their 60s and beyond, proactive measures can help maintain or improve swallowing function. These techniques can be beneficial for managing normal age-related changes and may also be part of a prescribed treatment plan for dysphagia.
- Tongue-Strengthening Exercises: The tongue is essential for pushing food into the pharynx. Exercises like pressing the tongue against a spoon or the roof of the mouth can build strength.
- Improving Head and Body Posture: Adjusting posture, such as performing a chin tuck maneuver, can help protect the airway during swallowing. An SLP can provide personalized guidance on optimal positioning.
- Modifying Food Texture: Making simple changes to diet, such as choosing softer, moist foods and avoiding dry, crumbly items, can make swallowing easier and safer. Using sauces and gravies can help.
- Encouraging Hydration: Staying well-hydrated helps promote saliva production, which is important for swallowing, particularly with dry foods.
- Monitoring Medications: Many common medications can cause dry mouth, which impedes swallowing. Regular check-ins with a doctor about medications can help mitigate this side effect.
When to Seek Professional Help
While subtle changes in swallowing speed are normal, consistent difficulty is not. If you or a loved one in their 60s exhibits any of the following signs, it is important to consult a healthcare provider for a referral to an SLP:
- Frequent coughing or choking during meals.
- A feeling that food or pills are getting stuck in the throat.
- Changes in voice quality, such as a wet or gurgly sound after swallowing.
- Unexplained weight loss or dehydration.
- Recurrent chest infections or pneumonia.
An SLP can perform a clinical or instrumental assessment, such as a videofluoroscopic swallowing study (VFSS), to pinpoint the exact nature of the swallowing issue and recommend a targeted treatment plan.
Conclusion: Interpreting Your Swallowing Rate in Your 60s
For a person in their 60s, the average Repetitive Saliva Swallowing Test (RSST) score is around 6.7 swallows in 30 seconds, a slight decrease from younger years. This rate can serve as a useful benchmark, but it is important to interpret it in context. Normal aging, or presbyphagia, involves a natural slowing of the swallowing process due to changes in muscle strength and coordination. However, significant and frequent difficulties, such as consistent coughing, choking, or unexplained weight loss, may indicate dysphagia and warrant professional medical attention. By understanding the physiological changes associated with age and being aware of the signs of dysphagia, you can take proactive steps to maintain healthy swallowing function and overall well-being. For further reading on swallowing disorders and treatment options, the National Foundation of Swallowing Disorders is an excellent resource.
