Alleviating Sleep Disorders through targeted intervention using Restorative - Therapeutic Surfaces in New Zealand

Authored by Dr. Moses Satralkar, Sleep Specialist

Defining Sleep Disorders

Circadian rhythms are natural rhythms of the human body which are periodic or repetitive over a 24-hour cycle. These intrinsic rhythms include sleep-wake cycles, hormone secretion, body temperature, metabolic cycles, cardiovascular rhythm, cognitive performance, immune function, etc. The supra-chiasmatic nucleus (SCN) is the human body clock or biological clock. It acts as a ‘master pacemaker’ to synchronize intrinsic physiological rhythms by receiving inputs from external environmental cues known as ‘zeitgebers’ (or time givers) such as light-dark cycles, temperature, social cues, food, medication, exercise, etc. The major function of the SCN is to receive light input to align internal time with the external environment to control melatonin secretion thereby modulating sleep (Fig 1). Often times, circadian dysfunctions may occur during the process of ‘entrainment’ or tuning of the internal body clock with external environmental cues causing desynchronization of the clock resulting in onset of what we commonly refer to as sleep disorders.

Fig 1: Functions of Supra Chiasmatic Nucleus (SCN) the Human Body Clock

Sleep disorders may be caused by physical or mental conditions, genetics, side effects of ailments, medication, lifestyle factors, hormonal changes, ageing, environmental factors, etc. There are different types of sleep disorders that are categorized as dyssomnias or parasomnias which are further segregated into far more complicated subdivision of myriads of disorders. Circadian rhythm sleep disorders include delayed sleep-wake phase disorder (DSWPD), advanced sleep wake phase disorder (ASWPD), irregular sleep-wake rhythm phase disorder (ISWRPD), Jet-lag disorder, Shift-work disorder, etc. This article succinctly covers four  commonly known sleep disorders shown in Fig 2. Sleep is directly influenced by one extrinsic factor, one of which is bedding or sleep surface. Since the mattress is directly relational to sleep as a surface, it has been proven scientifically that modulating sleep surfaces does help improve sleep latency (the time it takes to fall asleep), sleep efficiency (percentage of time spent in deep sleep) and total sleep cycle duration (to ensure fully energized wake cycles).

Fig 2: Common Sleep Disorders

Prevalence of Sleep Disorders in New Zealand

The following colour pie chart (Fig 3) depicts common different sleep disorders among adults in New Zealand, based on the most recent data-surveys over the past two decades by Government agencies.

Insomnias: Currently, 25% of adults have chronic sleep problems, with insomnia as the most common sleep disorder. Insomnia grew from 13% in 2001 to appx 25% in 2025 in New Zealand. Thus, as a public health issue, it affects approximately one in four adults in New Zealand due to a combination of lifestyle (eg. addictions), environmental (eg. lack of exposure to adequate sunlight), psychological (eg. stress), and systemic health factors (eg. ailments or ageing).

Obstructive Sleep Apnea (OSA): About 3% of adults have OSA, but prevalence varies by gender and ethnic background; showing that Maori men are more likely to have it than non-Maori men or general multi-ethnic population of women seen in Fig 4.

Other or Unspecified Sleep Disorders: The rest of the problems cover a broad-spectrum range of circadian disorders including parasomnias, less common sleep-related breathing or movement disorders.

These statistics highlight the significant burden of sleep problems in New Zealand, necessitating the need for ongoing awareness and targeted interventions one of which is designing restorative-therapeutic sleep-surfaces and cutting-edge sleep-systems apart from medication. 

Fig 3: Sleep Disorders in New Zealand Adult Populations with exacerbation of Insomnias

Fig 4: Ethnic Distribution of Obstructive Sleep Apnea in New Zealand

Innovations in Material Science influencing Sleep

Innovative surfaces play a role in ‘sleep medicine’ whereby they can either complement medication for sleep disorders or even minimize dependence on medication as the only remediation. I believe we need far more comprehensive information to enable people to make informed choices on how to customize sleep surfaces and sleep environments to overcome sleep disorders. Majority of people are not aware of the significance of the composition of sleep surfaces. This isn’t just a comfy-vs-uneasy or tossing-vs-tranquil debate but a far more intricate issue where each material has the capacity to influence the quality of sleep. This article provides a foundational basis to understand how different types of materials can maximize potential for overcoming sleep impairment. We need to explore the specific ways in which bedding materials in the retail industry impact sleep disorders to emphasize the important connection between our sleep setting and our overall health.

It is also necessary to appreciate that developments in material science and sleep systems have benefited lifestyles worldwide to produce and manufacture a fascinating range of beds, mattresses and accessories such as sheets, pillows, duvets, toppers, adjustable bases etc. These directly impact sleep architecture which is normal succession of sleep stages during a night’s sleep. Culturally different ethnic-communities have preferences on using different kinds of sleep surfaces that enhance their sleep patterns. Few prefer firm surfaces others medium and others plush with different materials. There is no one size, or one make that fits all. Each person or couple is unique; based on his/her body mass index (BMI) they need different pressure zones for enhancing sleep in a sleeping posture. Wrong selections do not allow them to sleep properly at all. Factors like the firmness of mattress, types of springs, the support of pillows, thermoregulation, and the very makeup of regular bedding can all influence sleep patterns across different age groups or ethnicities strongly. The right bedding can also combat sleep disturbances caused by hypersensitive skin reactions or dust/allergies. Hypoallergenic materials like bamboo and microfiber resist common allergens like dust mites and mould.

Correlating Sleep Disorders and Restorative Therapeutic Surfaces.

Quality of sleep has been shown to improve with high-quality bedding. This next section elucidates how bedding choices can improve common sleeping disorders.

Insomnia, defined as having difficulty falling asleep, maintaining sleep, or obtaining restorative sleep, is a common problem that affects millions of people world-wide. Although there are many causes of insomnia which are multi-faceted and may include psychological, physiological, or environmental influences, it is now evident that silk bedding can have a positive impact over other materials. Moreover, a mattress that is too firm can cause uneven pressure points and frequent wakings. On the flipside, if a mattress is too soft there may be lack of support, causing improper alignment of the spine and thus producing back and joint pain, making sleeping difficult.

Insomnia is usually best treated using a mattress that is a medium firm, custom made to order, ensuring ergonomic zoning in the mattress to ease surface tension corresponding to the body’s main pressure points. The five key pressure points while on a sleeping surface are the head, shoulders, hips, knees and ankles. Currently in New Zealand, there are mattresses which may be designed as unzoned or subdivided into three zones, five-zones or seven-zones. The five-zone mattresses are quite effective and suitable for adults and couples. However, a high ergonomic mattress providing the seven-zone pressure relief system could work best for people suffering from insomnia or neurological or orthopedic ailments. A hybrid mattress combing memory foam and latex is generally most effective with zones packed with high tensile pocket springs. A corresponding medium sized pillow will work better to align the spinal posture adequately to induce sleep quicker. Costings of different manufacturers and suppliers vary, however, invariably investment in high quality therapeutic surfaces has known to improve health sustainably over the long term.

Few studies have examined the evidence for the efficacy of special mattresses and bedding including an adjustable base for the treatment of insomnia and chronic snoring. The elevation provided by an adjustable remote-controlled base elevates the upper half of the body to ease breathing through constricted nasal cavities or trachea to improve airflow and expand lung capacity. The zero-gravity (Zero G) position induced by the adjustable bases enhance better blood circulation. Earlier studies in the Journal of Clinical Sleep Medicine also narrated how a temperature-regulating mattress influenced the sleep quality of people with insomnia. The improvement in both sleep continuity and total sleep time in the experimental group was statistically significant when compared to the control group sleeping with standard beds. This emphasizes the need for a comfortable sleep temperature that isn't too hot or too cold. These findings emphasize the importance of personalized sleep systems according to body weight, sleep position, and thermoregulatory preferences.

Sleep Apnea is another common sleep disorder that has impacted overall health. Sleep apnea is characterized by repeated interruptions of regular breathing throughout the night that causes snoring, gasping, choking, pauses during breathing, frequent awakenings and groggy feeling during the day. Though the commonly used therapy for sleep apnea is continuous positive airway pressure (CPAP), associated bedding may be a complementary component to help enhance sleep quality and treatment of chronic symptoms. The most direct impact comes through positional therapy using mattresses, pillows, or devices that help keep a person sleeping on their side, rather than their back. Sleeping on the back can worsen obstructive sleep apnea (OSA) because the tongue and soft tissues may collapse backward and block the airway. Side-sleeping helps keep the airway more open and reduces apnea events for most people. Hence a mattress which encourages uniform rather undulating alignment of the spine can help to open the airway and can minimize the severity of apneic episodes. Undulating mattresses that are overly soft, by contrast, could worsen sleep apnea by allowing the neck to flex too much, narrowing the airway.

People with sleep apnea typically do well with a double spring mattress that provides customized support and pressure relief, especially those with high body mass index (BMI). Temperature regulation is essential for sleep apnea. Too much insulation can exacerbate sleep apnea due to overheating, hence pure (natural) latex is generally considered better than synthetic latex. Natural latex offers superior durability, breathability, and hypoallergenic properties compared to synthetic latex, making it a more comfortable and potentially healthier choice for individuals with sleep apnea. Cooling gel layers or gel-infused foams may be better as a thermoregulating surface to lower the body temperature. A breathable fabric is better than a synthetic fabric or polymer. Breathable, natural fabrics like cotton, linen, and bamboo can help regulate body temperature and promote better airflow, which is particularly helpful for conditions like sleep apnea. Additionally, weighted blankets have shown promise in reducing anxiety and improving sleep for some individuals. 

Narcolepsy is another chronic neurological sleep disorder. Symptoms include sleepiness and a propensity to abruptly fall asleep during inappropriate day hours. This results from the brain's inability to appropriately define fixed sleep-wake cycles. Other symptoms of narcolepsy include hypnagogic hallucinations (strong dreamlike experiences during sleep or wakefulness), sleep paralysis (temporary incapacity to move or speak during sleep or wakefulness), and cataplexy (sudden muscle weakness brought on by strong emotions). The actual cause usually is loss of neurons in the brain that produce hypocretin, also referred to as orexin, which aids in regulating wakefulness, is frequently the precise cause. Medication, lifestyle changes, and sleep patterns can all help control symptoms. Medium to medium-firm mattresses is often recommended because they accommodate a variety of sleep positions, which is beneficial for those who may nap at irregular times and in different positions. Features such as pressure-relieving memory foam or latex, spinal alignment support, and even temperature regulation technology help reduce discomfort, minimize disturbances, and promote deeper sleep cycles at night.

 Restless legs syndrome (RLS) is a neurological condition involving an uncontrollable urge to move the legs, often with an unpleasant sensation. The symptoms of RLS tend to aggravate when at rest or not doing any activity and can have a marked effect on sleep. There's no one bedding product that will cure a case of RLS, but the right array of bedding can alleviate its symptoms and improve sleep. If an excellent mattress is supportive and relieves the necessary pressure, there is less discomfort and kicking of the legs. When the spine remains in proper alignment, tension and pain in one’s legs can be reduced, and, in turn, the frequency of RLS symptoms can be reduced. A high-profile pillow can provide the necessary support to one's neck and head that may result in a state of complete relaxation. The temperature of the bedding is also key; RLS sufferers often prefer a cooler bed to reduce symptoms. So, cotton sheets and light blankets are most suitable. In addition, certain bedding can cause RLS symptoms to worsen in some people. For example, some people experience increased RLS symptoms when using artificial or chemically based bed linen. Opting for natural, hypoallergenic sources of bedding can be advantageous in minimizing irritants and upgrades the quality of sleep. Regularly washing sheets is crucial to help rid the bed of potential allergens that can exacerbate RLS symptoms. Additional research has indicated that mattresses that offer very good support to the spinal column, particularly lower back, improve the quality of sleep-in restless sleepers. 

Debunking Bedding ‘Myths’

It is also essential to debunk “widespread myths” about mattresses. These misunderstandings are widespread in the bedding industry as products are frequently marketed based on aggressive advertising, not on facts. It is important to identify these myths to make the best, most restorative choice to cope with sleep disorders. One of these is that a “firmer mattress is a better one”. That is analogous to overuse of the “harder is better” fallacy which may not be suitable for insomnias and parasomnia. Firmness is crucial, but the perfect amount of firmness can differ a lot depending on personal factors such as body mass index, favorite sleeping position, and existing health issues. Another myth is to sleep “in” snugly rather than “on” the surface. This compares two contrasting ends of the spectrum. A mattress that’s too soft and lacks support will fail to support the spine in proper alignment, will strain and put pressure on joints, and may even aggravate OSA and cause musculoskeletal problems.  Well-made hybrid mattresses accommodate the curves of the body compress adequately, without creating uneven tension points. Another source of confusion is “one type of bed or foam type is best for all health problems”. However, this again may not be entirely accurate.

Conclusion

In summary, there is a definite link between bedding and sleep related issues. While bedding won’t directly cure or overcome a sleep disorder, the right mattresses, pillows and other bedding elements can certainly alleviate symptoms and improve sleep quality in those suffering from different kinds of sleep issues, including insomnia, sleep apnea, RLS and other types of disorders. This same fact even applies to parasomnias, or unusual actions and physiological events that occur while a person is asleep. For instance, a mattress or pillow that was contributing to frequent nighttime arousals could heighten the risk of sleepwalking in a predisposed person. On the other hand, a relaxing sleep environment could alleviate sleep disturbances and subsequently decrease the risk of parasomnias.

References:

1. Circadian Rhythms and the Suprachiasmatic Nucleus (SCN)

Reference(s):

• Moore, R. Y., & Eichler, V. B. (1972). Loss of a circadian adrenal corticosterone rhythm following suprachiasmatic lesions in the rat. Brain Research, 42(1), 201-206. 
• Mistlberger, R. E., & Skene, D. J. (2005). Social influences on mammalian circadian rhythms: animal and human studies. Biological Reviews, 80(3), 465–480. 
• Czeisler, C. A., & Gooley, J. J. (2007). Sleep and Circadian Rhythms in Humans. Cold Spring Harbor Symposia on Quantitative Biology, 72, 579–597. 

2. Prevalence of Sleep Disorders in New Zealand

Insomnia Prevalence (25% of adults):

• Ministry of Health NZ. (2019). Annual Data Explorer 2019/20: New Zealand Health Survey: Insufficient Sleep.
• Paine, S. J., Smith, C., & Gander, P. H. (2018). Insomnia prevalence and consequences in New Zealand: Disparity between Māori and non-Māori. Australian and New Zealand Journal of Public Health, 42(6), 590-596.

Increase from 13% (2001) to 25% (2025):

• Paine, S.J., Gander, P.H., Harris, R., & Reid, P. (2004). Prevalence and consequences of insomnia in New Zealand: disparities between Māori and non-Māori. Australian and New Zealand Journal of Public Health, 28(2), 116-125. 
• Ministry of Health NZ. (2022). "Sleep" in Annual Data Explorer 2021/22.

Sleep Apnea Prevalence (3% adults, ethnic/gender differences):

• Brabyn, S., Cormack, D., Smith, C., & Gander, P. (2022). Obstructive sleep apnea in New Zealand adults: Prevalence and ethnic differences. Sleep Health, 8(1), 1-8.
• Ancoli-Israel, S., et al. (1995). Sleep-disordered breathing in community-dwelling elderly. Sleep, 18(4), 291-298.

3. Influence of Bedding/Surfaces on Sleep

Restorative Effects and Sleep Latency Improvements:

• Bertisch, S. M., et al. (2014). The role of the bedding environment in sleep quality: A systematic review. Sleep Medicine Reviews, 18(1), 87-94.
• Krystal, A. D., & Edinger, J. D. (2008). Measuring sleep quality: A review of subjective and objective measures. Sleep Medicine Reviews, 8(2), 123-138.

Zoning (3, 5, 7-zone mattresses), Pressure Relief:

• Radwan, A., et al. (2015). Effect of different mattress designs on promoting sleep quality, pain reduction, and spinal alignment: A systematic review of studies. Ergonomics, 58(1), 23-41.

Temperature Regulation and Sleep:

• Okamoto-Mizuno, K., & Mizuno, K. (2012). Effects of thermal environment on sleep and circadian rhythm. Journal of Physiological Anthropology, 31(1), 14. 
• Krauchi, K., et al. (1999). Warm feet promote the rapid onset of sleep. Nature, 401(6748), 36-37.

Adjustable Beds and Zero Gravity:

• Thorpy, M. J., & Yager, J. (2011). Sleep Disorders and Sleep Deprivation: An Unmet Public Health Problem. Sleep, 34(5), 555–556.
• Park, K. E., et al. (2017). The impact of adjustable/zero-gravity beds on upper airway patency for obstructive sleep apnea. Sleep & Breathing, 21, 537–543.

4. Specific Sleep Disorders & Bedding

Insomnia (Medium-firm mattresses and zoning):

• Jacobson, B. H., Boolani, A., & Smith, D. B. (2009). Changes in back pain, sleep quality, and perceived stress after introduction of new bedding systems. Journal of Chiropractic Medicine, 8(1), 1-8.

Obstructive Sleep Apnea (Side sleeping, double spring mattresses, natural latex):

• Oksenberg, A., et al. (2000). Body position and obstructive sleep apnea syndrome: A therapeutic effect of sleep position. Sleep, 23(6), 745-751. 
• Jones, S. E., et al. (2021). Bedding materials for adult sleep apnea: a systematic review. Nature and Science of Sleep, 13, 2035-2045.

5. Restless Legs Syndrome (Bedding, temperature, washing sheets):

• Trenkwalder, C., et al. (2016). Restless legs syndrome–current therapies and latest advances. Nature Reviews Neurology, 12(8), 434-445. 
• Allen, R. P., et al. (2003). Restless legs syndrome: diagnostic criteria, special considerations, and epidemiology. Sleep Medicine, 4(2), 101-119.

6. Debunking Mattress Myths (Individualization of Mattress Selection)

• Kovacs, F. M., et al. (2003). Effect of firmness of mattress on chronic non-specific low-back pain: randomized, double-blind, controlled, multicentre trial. The Lancet, 362(9396), 1599–1604.
• Drake, C. L., et al. (2017). The subjective-objective mismatch in sleep perception among those with insomnia and sleep-state misperception: Implications for bedding choices. Sleep Medicine Reviews, 33, 36-43.

7. Ethnicity and Sleep Disparities (NZ-specific)

• Paine, S. J., et al. (2005). Prevalence and consequences of insomnia in New Zealand: disparity between Maori and non-Maori. Australian and New Zealand Journal of Public Health, 29(1), 22-28.
• Brabyn, S., et al. (2022). Obstructive sleep apnea in New Zealand adults: Prevalence and ethnic differences. Sleep Health, 8(1), 1-8.