Modern Americans have busier lives than ever. Between holding down one or more jobs to pay the bills, rushing the kids to football practice, and trying to squeeze an hour or two of leisure into our schedules, it often feels like there just aren’t enough hours in the day. With schedules like these, getting less than eight hours of sleep every night often seems like an easy sacrifice to make. However, we neglect our sleep at our own peril, particularly if we are diagnosed with, or predisposed to, diabetes.
How Diabetes Impacts Sleep
Diabetes has the potential to cause many or relatively few complications, depending on how well it’s managed. When not well managed, short-term impacts of high or low blood sugar can disrupt sleep, as can sleep disorders that may become more likely in those with chronically poor diabetes management.
Insomnia and fatigue
When blood sugar levels fall outside of a healthy range while we sleep, physiological responses in the body can disrupt sleep quality. If this occurs chronically, it can manifest as insomnia, and can leave us feeling tired and fatigued during the day.
When blood sugar levels climb too high, the body often responds with a frequent desire to urinate, as well as an increased sense of thirst. Flushing excess blood sugar through the kidneys into the urine is one of the body’s tools to combat hyperglycemia, but it induces excessive urination and a constant need to replace the fluids lost in the process. This can cause patients to wake frequently with an urgent need to visit the bathroom or grab a drink of water. Occasionally waking to urinate is normal, but doing so multiple times per night can add up to a fragmented and less restful sleep.
At the other end of the spectrum, low blood sugar levels can also be disruptive. Nightmares or night terrors, night sweats or chills, and irritability or confusion have all been reported as side effects of experiencing low blood sugar at night and can be disruptive if occurring frequently.
Co-morbid sleep disorders
Type 2 diabetics have been shown to have a greater risk of developing a number of complications, including several sleep disorders. Sleep disorders are characterized as conditions that impact some aspect of quality sleep, such as its duration, quality, or restfulness. These conditions are separate from diabetes itself, but diabetes can contribute to their development or progression.
One example is restless leg syndrome (RLS), which describes a condition causing an uncomfortable and uncontrollable urge to move one’s legs throughout the night. This can be extremely disruptive to one’s sleep, as well as the sleep of anyone sharing their bed. RLS can occur in the general population, but diabetics are thought to be particularly susceptible to it. This is likely due to the damage to nerves that can sometimes be caused by chronically high blood sugar known as peripheral neuropathy.
Obstructive Sleep Apnea (OSA) is another sleep disorder with a complicated relationship to diabetes. The disorder can occur in the general population but is thought to be both a risk factor for, and potentially a complication of, diabetes. This condition is characterized by the regular inability of a patient to intake sufficient oxygen throughout the night. This often leads to fragmented sleep and repeated episodes of wakefulness throughout the night. Some researchers have speculated that diabetic neuropathy may induce or worsen OSA through impairment of the body’s control over respiration.
How Sleep Impacts Diabetes
Just as many aspects of diabetes and its treatment can bear negatively on one’s quality of sleep, poor sleep appears likely to negatively impact diabetes management. While this correlation has been established, the precise mechanisms through which this relationship propagates remain the subject of ongoing research. However, experts have proposed several mechanisms by which poor sleep may affect insulin resistance, blood sugar levels, and general outcomes for diabetic patients.
Some experts have speculated that a poor night’s sleep sets off hormonal chain reactions culminating in increased blood glucose levels. For example, inadequate sleep is known to cause the release of the stress hormone cortisol. Cortisol in turn causes the liver to release glucose into the bloodstream, presumably to provide the body with more energy to deal with the stressful experience. While this important adaptation can help us in some situations, chronically high levels of cortisol like those in sleep-deprived patients are likely to wreak havoc on our ability to regulate blood sugar.
Another causal mechanism could be that dysregulated sleep disrupts our circadian rhythm, and with it, the control of important endocrine systems involved in metabolism and appetite. Leptin and ghrelin are two hormones which play vital roles in our metabolic processes, controlling when we feel hungry or satiated. By disrupting the rhythmic release of these chemicals, poor sleep could cause patients to overeat and further worsen their insulin resistance.
Still, it could be true that poor sleep and poor diabetes management are both caused by a third factor, making the correlation between sleep and blood sugar dysregulation non-causal. For instance, individuals with poor impulse control or discipline may struggle to keep a consistent and healthy sleep routine, while also struggling to maintain a meticulous approach to their diabetes care. However, given the wide range of known consequences of poor sleep, such as a long-term risk of cognitive decline and psychological distress, optimizing one’s sleep is almost universally advisable, even if it may only correlate with or indirectly contribute to positive diabetes outcomes.
Poor sleep as a risk factor
Poor sleep may contribute to new cases of type 2 diabetes, in addition to worsening outcomes in existing cases. Recall that type 2 diabetes, in contrast to type 1, is typically acquired or developed later in life, and results from the body’s inability to respond to the presence of insulin. Thus, factors which decrease the body’s sensitivity to insulin can serve as risk factors for type 2 diabetes. As it turns out, impaired sleep is likely such a factor, and several studies support this notion.
Studies have shown that as few as four consecutive nights of sleep deprivation can cause a staggering spike in insulin resistance. In addition, separate lines of research have shown certain sleep disorders to be significant risk factors for obesity and type 2 diabetes. Given these observations, it is unsurprising that one study found people who sleep for shorter duration to have roughly a 40% greater chance of developing type 2 diabetes than their counterparts who slept a full seven or eight hours. One expert summarized these findings by stating that trouble falling or staying asleep ought to be considered a risk factor for diabetes roughly equivalent to having a family history of the illness.
Coping Strategies for Diabetics with Sleep Issues
Existing evidence on the two-way relationship between sleep and diabetes paints an unpleasant picture. It also raises the question of whether diabetics can intervene in order to improve their sleep quality, and by extension, their condition. Individuals should only take action in this regard following consultation with their doctor. However, some general information on possible strategies for combatting poor sleep quality are described below.
In many cases, particularly where sleep impairment is not caused by a diagnosable sleep disorder, simple lifestyle changes can drastically improve sleep quality. For diabetics and non-diabetics alike, improving habits and routines around going to bed and waking up can help the body develop a more deeply ingrained circadian rhythm that can lead to more restful sleep. Broadly, this is referred to as sleep hygiene, and includes habits like ensuring screens and bright lights are put away well before bedtime, drinking fewer fluids in the evening to avoid waking to urinate, and engaging in calming activities like reading to help wind the body down for the night. These may seem like small things, but they’re worth getting right.
For diabetics specifically, proper diabetes management should make you less likely to experience blood sugar irregularities while sleeping, making you more likely to sleep well. Staying on top of insulin, blood sugar monitoring, exercise and diet are always important, but in the context of quality sleep, are also significant factors.
In some cases, doctors may determine that medical treatments for sleep quality may be warranted, particularly if they feel the sleep issues may worsen a diabetes diagnosis. The precise treatments offered will vary depending on the patient’s needs, whether less extreme measures have been attempted, and the nature of their sleep impairment, which may include a diagnosed sleep disorder.
A range of prescription medications currently exists for the general treatment of insomnia. These medications belong to several classes and work in a variety of ways. Some are only intended for short term or occasional use while others have been approved for treatment of more chronic cases. Many of these medications can create chemical dependencies in their users, and can cause the underlying insomnia to become worse once the medications are ceased (a phenomenon sometimes known as “rebound insomnia”). These and other side effects mean that they will not suit each individual case.
If your sleep issues originate from an OSA diagnosis, your first step will likely be to begin using a CPAP machine or other device to help maintain breathing throughout the night. If you are already using such a device, you may not be using it optimally. Research has shown that many users do not use their devices properly, and the difference between improper and ideal usage can result in profound increases in sleep quality and clinically significant improvements in waking blood sugar levels.