It is a common and often startling experience to learn you are making strange noises while asleep, especially when you are unwell. This nocturnal vocalization, often described as a moan or groan, is distinct from simple snoring. While the noises are typically harmless and temporary, they signal a change in your body’s breathing mechanics during sleep. Understanding the root cause involves examining how a temporary illness can influence your airway and breathing patterns.
Identifying Sleep Groaning
The sound is formally known as catathrenia, or nocturnal groaning, a relatively uncommon type of parasomnia. Catathrenia is characterized by a prolonged, monotonous groaning or moaning sound that occurs during the exhalation phase of the breathing cycle. It is important to differentiate this sound from snoring, which is caused by the vibration of soft tissues in the throat during inhalation. While true catathrenia is a chronic condition, many people experience temporary sleep groaning that shares the same characteristics when they are sick. The sleeper is usually completely unaware they are making the noise, which can be loud enough to disrupt a sleep partner.
The Physiological Mechanism of the Sound
The physical production of this groaning involves an active process within the larynx (voice box), rather than the passive vibration seen in snoring. The episode begins with a slow, deep inhalation, followed by a breath-holding period against a partially closed glottis. The glottis is the part of the larynx that contains the vocal cords. The subsequent sound is generated as air is slowly released during a prolonged exhalation through these partially closed vocal cords. This controlled release causes the vocal cords to actively adduct and vibrate, creating the characteristic low-pitched moan or groan.
Why Illness Acts as a Specific Trigger
Illness initiates or exacerbates groaning primarily due to the immediate impact of upper respiratory infection on airway structures, especially the larynx. Illnesses like the common cold, flu, or seasonal allergies lead to inflammation, known as laryngitis, which is the swelling of the vocal cords. Swollen and irritated vocal cords are more likely to vibrate when air is forced across them during prolonged exhalation. Increased mucus and congestion also force mouth breathing, altering the normal pressure dynamics within the airway, which can inadvertently facilitate the partial closure of the glottis during exhalation, triggering the groaning sound. Furthermore, the fragmented and altered sleep stages common during illness can make the respiratory control center in the brain more susceptible to the irregular breathing pattern that precedes the groan.
Management and When to Seek Professional Advice
For temporary groaning associated with a cold or flu, management involves treating the underlying illness and supporting the respiratory system. Using a humidifier in the bedroom can help soothe inflamed vocal cords and thin out excess mucus. Over-the-counter decongestants may also help reduce nasal and throat congestion that is contributing to the altered breathing patterns. Sleeping on your side may also reduce the frequency of the episodes, as positional changes can sometimes alleviate pressure on the airway.
While temporary groaning during illness is generally considered benign, seek professional medical advice if the groaning persists long after the illness has resolved. A consultation with a doctor or sleep specialist is warranted if the groaning is accompanied by symptoms such as gasping, choking, or noticeable pauses in breathing, which can indicate a more serious underlying sleep disorder. Persistent daytime fatigue or unrefreshing sleep should also prompt a medical evaluation to rule out other conditions.