Moaning during sleep in older adults has no single explanation. The sound can come from a recognized sleep breathing disorder called catathrenia, from chronic pain that the sleeping brain still registers, from neurological conditions like Parkinson’s disease or dementia, or from REM sleep behavior disorder, which is far more common in people over sixty than in younger adults. Because the causes overlap and the person making the sounds is almost never aware of them, figuring out what is actually happening usually requires more than just listening from the next room.
Catathrenia, the Formal Name for Nocturnal Groaning
Sleep medicine has a specific diagnosis for repetitive moaning or groaning during sleep: catathrenia. The pattern is distinctive. A person takes a deep breath in, then lets out a long, audible groan on the exhale, sometimes finishing with a shorter, louder moan before inhaling again. These episodes tend to come in clusters, especially during REM sleep and toward the end of the night. The groaning sound is produced by the vocal cords vibrating on expiration, and it can be remarkably loud, enough to wake a bed partner repeatedly even though the groaner typically sleeps through it undisturbed.1PubMed. Lamentations in the night: A systematic review on catathrenia
One wrinkle worth knowing: catathrenia usually starts in young adulthood. In a study of 47 patients, the average age of onset was around eighteen.2PubMed Central. Characteristics of clinical descriptive variables and polysomnographic findings of catathrenia That means an elderly person who has been groaning in their sleep for decades may well have classic catathrenia that was never formally diagnosed. But if the groaning is new and appeared only in later life, classic catathrenia becomes less likely, and other causes deserve a closer look.
There is also an atypical form of catathrenia that looks somewhat different. Instead of the long expiratory groans clustered in REM sleep, this variant involves short, roughly two-second moans that occur semi-continuously during lighter stages of non-REM sleep as well as REM sleep. This pattern tends to appear in people with some degree of upper airway obstruction.1PubMed. Lamentations in the night: A systematic review on catathrenia Because airway narrowing and collapse become more common with age, this atypical presentation may be more relevant to elderly groaners than the classic version. Pressure measurements during groaning episodes have shown mildly positive swings in the airway at the start of expiration, consistent with partial obstruction at the throat level.3PubMed. Catathrenia (nocturnal groaning): an abnormal respiratory pattern during sleep
A detail that surprised researchers: the groaning itself does not appear to fragment the groaner’s sleep quality in most cases. In a study analyzing over 400 groaning episodes, about four in five occurred during REM sleep, and the majority were associated with brief arousals in brain activity, though nearly half of the patients reported daytime sleepiness anyway.4PubMed Central. Catathrenia as a REM predominant disorder of arousal That sleepiness may stem from the same underlying sleep-architecture disruption that produces the groaning, or it may simply reflect the common experience of poor sleep in older adults for other reasons. The pathophysiology and optimal treatment for catathrenia remain unknown, which is frustrating for both patients and their families.1PubMed. Lamentations in the night: A systematic review on catathrenia
Pain That Surfaces During Sleep
Chronic pain is extremely common in older adults. Between a fifth and half of community-dwelling elderly people deal with ongoing pain, and the numbers climb sharply in care facilities, where up to four in five residents report at least one significant pain problem.5Clinics in Geriatric Medicine. Assessment and Management of Pain in the Elderly Arthritis, degenerative joint disease, osteoporosis, cancer, and neuropathic conditions all accumulate with age. When someone is awake, they can shift position, take medication, or use distraction. During sleep, those coping tools vanish, and the body’s response to pain may emerge as moaning, grimacing, or restless movement.
Geriatric pain assessment guidelines specifically list moaning as a behavioral indicator of pain, alongside grimacing, agitation, appetite changes, and altered mental status.5Clinics in Geriatric Medicine. Assessment and Management of Pain in the Elderly This is especially important for people who can no longer verbally communicate their pain due to cognitive decline. A family member or caregiver hearing moaning at night should consider whether the person has an undertreated pain condition. In nursing home settings, staff are trained to recognize nighttime vocalizations as a potential sign that pain management needs adjustment, but in home settings, the connection between moaning and pain is easy to miss.
Pain-related moaning tends to sound different from catathrenia. It does not follow the rhythmic inhale-long exhale pattern, is not clustered in REM sleep, and is often accompanied by other signs of distress such as furrowed brows, body tension, or restless repositioning. If a person who groans in their sleep also has known painful conditions, better pain control during the evening and night is worth discussing with a doctor before pursuing any sleep-specific diagnosis.
REM Sleep Behavior Disorder
During normal REM sleep, the brain temporarily paralyzes most voluntary muscles so that dreams stay in the mind and do not translate into physical action. In REM sleep behavior disorder, that paralysis is incomplete or absent, and people physically act out their dreams. They may kick, punch, shout, laugh, cry, or moan. The disorder is rare in younger adults but becomes far more common after age sixty, and it is significantly more prevalent in men.
A study of 62 patients with isolated REM sleep behavior disorder, averaging about 68 years old, found that over half of all REM sleep epochs contained motor events and about one in twenty contained vocalizations. The most common manifestations were simple minor movements and mild-intensity vocalizations.6PubMed. Audiovisual analysis of the diagnostic video polysomnography in patients with isolated REM sleep behavior disorder That “mild intensity” category is where moaning and groaning often land. The person is not screaming or shouting; they are making low, sustained vocal sounds as part of dream enactment that registers as moaning to a listener in the same room.
REM sleep behavior disorder matters beyond the noise it produces. Research over the past two decades has shown that the disorder is strongly associated with later development of neurodegenerative diseases, particularly Parkinson’s disease and a related condition called Lewy body dementia. An elderly person newly making unusual sounds and movements during sleep deserves a medical evaluation, because the sleep disorder may be an early signal of neurodegeneration that has not yet produced daytime symptoms.
Neurological Conditions That Cause Vocalization
In people already living with Parkinson’s disease or dementia, groaning and moaning can occur both during sleep and during wakefulness, driven by changes in brain circuits that normally regulate automatic behaviors. A case report documented a patient with long-standing Parkinson’s disease whose purposeless groaning became increasingly intrusive over time, occurring throughout the day, with the patient becoming quiet only upon falling asleep.7PubMed Central. Purposeless Groaning in Parkinson’s Disease This is the opposite pattern from catathrenia, where groaning happens exclusively during sleep. The mechanism is thought to involve disinhibition of frontal brain circuits, meaning the parts of the brain that normally suppress repetitive, purposeless sounds lose their ability to do so.
In dementia, nighttime vocalizations overlap with a phenomenon called sundowning, where neuropsychiatric symptoms like agitation, confusion, and anxiety emerge or worsen in the late afternoon and evening. Sundowning is highly prevalent in people with dementia and appears to be driven partly by deterioration of the brain’s internal clock, specifically the region of the hypothalamus that regulates circadian rhythms, combined with reduced production of melatonin.8PubMed Central. Sundown syndrome in persons with dementia: an update Moaning, calling out, and repetitive vocalizations during the night may be part of this broader pattern of nighttime neuropsychiatric disturbance rather than a sleep-specific disorder.
Distinguishing between these neurological causes matters practically. If the moaning is an extension of daytime groaning related to Parkinson’s, treatment focuses on the underlying disease and its motor and behavioral symptoms. If the moaning accompanies confusion and agitation consistent with sundowning, the approach involves circadian interventions like light therapy, melatonin, and environmental adjustments. And if the moaning occurs only during REM sleep alongside dream-enacting movements, the focus shifts to managing the sleep disorder itself.
How Sleep Moaning Differs From Sleep Talking
Families sometimes describe nighttime moaning as “talking in their sleep,” but the two phenomena are distinct both in how they sound and in what is happening in the brain. Sleep talking in the strict sense refers to verbal production, words and sentences that vary in length and intelligibility. Research examining the brain activity preceding different sleep vocalizations found that verbal sleep talking is preceded by specific changes in electrical activity in the left parietal region, a brain area involved in language processing. Non-verbal vocalizations like moaning did not show these same changes.9Sleep. Sleep talking versus sleep moaning: electrophysiological patterns preceding linguistic vocalizations during sleep
In practical terms, sleep talking involves the language system activating during sleep, while moaning bypasses language entirely. Someone who moans during sleep is not trying to say something. The sound is generated by air passing over vocal cords during a particular breathing pattern or by autonomic vocal responses to pain, dream content, or neurological dysfunction. This distinction is useful because it helps narrow the possible causes. New-onset sleep talking in an elderly person can be benign, while new-onset moaning or groaning, especially if accompanied by movement, raises a different set of diagnostic questions.
The Toll on Bed Partners and Caregivers
One of the most consistent findings across studies of nocturnal groaning and REM sleep behavior disorder is that the person producing the sounds is often unaware of them, while the person sharing the bed or the room suffers significantly. In catathrenia, it is almost always the bed partner’s complaint that brings the condition to medical attention, not the groaner’s own distress.4PubMed Central. Catathrenia as a REM predominant disorder of arousal
The impact goes beyond lost sleep. A study comparing spouses of patients with REM sleep behavior disorder to spouses of patients with obstructive sleep apnea found that both groups reported high rates of insomnia, anxiety, and depressive symptoms. But spouses of people with REM sleep behavior disorder reported even greater impairment in quality of life and in their marital relationship. Nine in ten of these spouses said they were disturbed by the nighttime symptoms, and nearly two-thirds reported having been physically injured during sleep by their partner’s dream-enacting movements.10Sleep Medicine. Caring burden of REM sleep behavior disorder – spouses’ health and marital relationship
For caregivers of elderly people with dementia-related nighttime vocalizations, the situation compounds. The caregiver may already be managing challenging daytime behaviors, and broken sleep from nighttime moaning erodes the energy and patience needed to provide care. In institutional settings, a resident who moans loudly can disturb an entire hallway of other residents. This is one of the reasons nighttime vocalization is taken seriously in geriatric medicine even when the moaning itself is harmless to the person producing it.
Position, Timing, and Other Patterns Worth Noticing
If you are trying to describe an elderly person’s nighttime moaning to a doctor, a few observations can help narrow down the cause. The position the person is in matters: catathrenia groaning events are more frequent when someone is lying on their back than on their side.2PubMed Central. Characteristics of clinical descriptive variables and polysomnographic findings of catathrenia This is consistent with the role of partial airway obstruction, which worsens in the supine position.
Timing within the night also provides clues. Catathrenia tends to cluster in the second half of the night, when REM sleep periods are longest. REM sleep behavior disorder follows the same pattern, since it manifests only during REM. Pain-related moaning, by contrast, may occur at any point during the night and often coincides with position changes or periods of lighter sleep. Dementia-related vocalizations may start before the person is fully asleep, blurring the line between daytime agitation and a sleep disorder.
The sound quality itself is informative. The rhythmic inhale-groan-inhale pattern of catathrenia is fairly recognizable once you know what to listen for. It sounds almost musical, a sustained low note on each exhale. Moaning from pain tends to be irregular and accompanied by physical signs of distress. Vocalizations from REM sleep behavior disorder are often more varied and may include mumbling, shouting, laughing, or crying mixed with movement.
What a Sleep Evaluation Involves
When nighttime moaning in an elderly person is frequent enough to be disruptive or concerning, the standard diagnostic tool is a video-assisted sleep study, or video polysomnography. This records brain waves, eye movements, muscle activity, breathing, oxygen levels, and audio-video of the person’s behavior throughout the night. It can distinguish catathrenia from REM sleep behavior disorder, from obstructive sleep apnea with associated groaning, and from other parasomnias.
For catathrenia specifically, earlier studies pooling data from literature reviews of all published cases found no clear association with any predisposing factors or underlying disease, which makes it frustrating to predict or prevent.11Journal of Sleep Research. ‘Nocturnal groaning’: just a sound or parasomnia? For REM sleep behavior disorder, the sleep study is essential not just for confirming the diagnosis but for establishing a baseline, since the disorder is associated with future neurodegenerative disease and may warrant neurological follow-up.
In cases where the moaning is suspected to stem from pain or dementia rather than a primary sleep disorder, a formal sleep study may be less useful than a careful clinical assessment of pain management, medication side effects, and the overall pattern of nighttime behavior. Geriatric medicine specialists and palliative care teams are often better positioned to address these causes than sleep clinics.
Practical Steps for Families
If you live with an elderly person who moans during sleep, a few things are worth trying before pursuing a full medical workup. Encouraging side-sleeping can reduce both catathrenia and obstructive airway sounds. Reviewing evening medications with a pharmacist or doctor is worthwhile, since certain drugs, especially sedatives and some antidepressants, can worsen REM sleep behavior disorder or alter sleep architecture in ways that increase vocalizations. Making sure pain is adequately managed through the night, including timed doses of analgesics if needed, addresses one of the most treatable causes.
For bed partners, practical coping measures matter as much as diagnosis. White noise machines, earplugs, or sleeping in a separate room during particularly bad stretches are not signs of failure. The research on caregiver burden makes clear that losing sleep night after night has real consequences for physical and mental health.10Sleep Medicine. Caring burden of REM sleep behavior disorder – spouses’ health and marital relationship Preserving the caregiver’s sleep is itself a form of caregiving.
Recording the sounds on a phone is one of the most useful things a family member can do. A thirty-second clip of the moaning, along with notes about when it happens, what position the person was in, and whether they seemed distressed, gives a clinician far more information than a verbal description. Many sleep disorders can be provisionally identified just from the audio pattern, which helps determine whether a formal sleep study is warranted or whether the issue is better addressed through pain management or neurological care.