Author: Superadmin

Given the likelihood that 84% of the population will experience back pain in their lifetimes, there is a high demand for treatments to address this condition [1]. Due to its ability to assuage back pain, along with neck pain and headaches, chiropractic adjustment is one such option [2]. Generally, adjustment procedures on the back consist of a doctor of chiropractic applying a controlled force to the patient’s spinal joints, either with their hands or an instrument [2]. If successful, the patient will experience diminished or eliminated stiffness and soreness [2]. There are many methods for performing a chiropractic adjustment, including manual adjustment and drop table [2].

Manual adjustment involves chiropractors using their hands to apply quick, low-amplitude thrusts on the patient’s spinal joints [3]. It is one of the most common forms of chiropractic adjustment, owing both to the general population’s familiarity with the technique and doctors’ tendency to be comfortable administering the method [3]. Manual adjustment is often successful when treating joint soreness, pain, or stiffness [3]. More specifically, it may be an ideal technique to use when other methods, such as laser or infrared technology, have failed to relieve patient’s conditions [3].

There is no single ideal candidate for manual chiropractic adjustment: anyone who suffers from back, neck, or other joint pain, stiffness, or soreness can benefit from this form of treatment [3]. It can relieve subluxations caused by toxins, trauma, or mental difficulties [3]. Overall, manual adjustment is a highly versatile chiropractic technique.

An alternate form of chiropractic adjustment is the drop table method. For drop table adjustments, the chiropractor uses the force of gravity, administered via a controlled drop in a segment of the treatment table, to settle the patient’s spine into place [4]. It requires considerably less applied force than other chiropractic adjustment techniques [1]. Drop table has proven successful in treating many joint conditions, perhaps most notably sciatica, without subjecting neither the patient nor the chiropractor to particularly forceful treatment sessions [1, 4].

Drop table can be especially beneficial for patients who are pregnant, weigh more, or experience difficulty moving around [1, 4]. Because patients lie on the table during the treatment, they do not need to expend much effort [1]. To best cater to patients’ conditions, chiropractors should carefully choose a table constructed by a reputable manufacturer with easily accessible tension knobs, so as not to hit the patient’s knees [4]. By choosing the right table, chiropractors can render the drop table technique an appropriate treatment option for the greatest number of patients [4].

When choosing between the two techniques, there are several considerations to keep in mind. For one, manual adjustment requires no expenditure on instruments, while the drop table can be an expensive piece of technology [5]. Conversely, the drop table requires minimum energy expenditure from practitioners, while manual adjustment can lead to chiropractors experiencing soreness over time [5]. In terms of efficacy, instrument-assisted techniques, such as drop table, appear to be at least as effective as manual adjustments [5]. However, drop table may be best for sensitive patients because it avoids placing them in the uncomfortable twisting positions associated with manual adjustment [6].

Ultimately, chiropractors should consider each procedure’s effects on the physician, ability to meet the patient’s needs, and economic impact to choose between manual or drop table chiropractic adjustment. 

References

[1] C. DeBusk, “Drop table treatments found to provide relief for patients with sciatica,” Chiropractic Economics, Updated January 15, 2015. [Online]. Available: https://www.chiroeco.com/drop-table-treatments-found-to-provide-relief-for-patients-with-sciatica/.

[2] Mayo Clinic, “Chiropractic adjustment,” Mayo Clinic, Updated November 26, 2020. [Online]. Available: https://www.mayoclinic.org/tests-procedures/chiropractic-adjustment/about/pac-20393513.

[3] Premier Chiropractic & Wellness, “Manual Adjustments from Chiropractors: What Are They?,” Premier Chiropractic & Wellness, Updated August 1, 2020. [Online]. Available: https://chiropractormhk.com/manual-adjustments/manual-adjustments-from-chiropractors-what-are-they/.

[4] C. DeBusk, “Are chiropractic drop tables safe?,” Chiropractic Economics, Updated July 13, 2018. [Online]. Available: https://www.chiroeco.com/chiropractic-drop-table-safety/.

[5] T. Beyshok, “Chiropractic Adjustments: Pros and cons of manual vs. Instrument-assisted,” Chiropractic Economics, Updated June 2, 2016. [Online]. Available: https://www.chiroeco.com/chiropractic-adjustments/.

[6] R. Grassi, “Chiropractic Subluxations and Adjustments,” Spine Universe, Updated November 11, 2019. [Online]. Available: https://www.spineuniverse.com/treatments/chiropractic/chiropractic-subluxations-adjustments.

In response to a rapidly changing professional landscape, individuals are spending increasing amounts of time sitting down, using their phones, and not exercising on a regular basis. This is resulting in postural issues and orthopedic challenges that manifest in various ways, including pain in the lower back and neck – up to one quarter of patients discharged from physical therapy clinics are currently estimated to suffer from lower back pain ¹. Specific medical conditions, such as sciatica, herniated discs, or muscle spasms, alongside stress, exacerbate these difficulties, affecting patients’ range of motion and daily functioning. Traction exercises may be very effective at relieving associated pain and improving patient mobility by creating space in between vertebrae, straightening gravity-incurred spinal curves, decreasing muscular tension, and improving blood flow ^2,3. While effectively implemented by chiropractors and physical therapists, these may also be learned, practiced, and performed by patients themselves at home.

Home traction exercises take on a variety of forms tailored to patient clinical presentation, comorbidities, age, and desired outcomes. For example, a recent study found that home traction exercises for the neck provided pain relief for a 30-year-old patient suffering from cervical radiculopathy ⁴. Following three weeks of therapy, the patient experienced improved neck pain and radicular symptoms, as well as reduced numbness in his hand; in addition, he regained nearly normal range of cervical motion. Cervical traction as such is a frequently recommended intervention for neck pain which can be performed at home on a regular basis as a long-term preventive measure.

Additional recommended exercises to stretch out the neck and back include lying down leg presses, prayer yoga poses, and various back stretches using chairs or desks as support – all of which require minimal equipment and are easy to implement ⁵. In general, positions are to be held for 10-15 seconds and repeated as often as needed for pain relief. The exercises themselves are recommended to be repeated 2-3 times per day or throughout the day, as needed.

This being said, some studies found no differences in outcomes in between home traction exercises and machine-mediated decompression ⁶, as reported outcomes differ across patient population and setting. Furthermore, there remains a number of clinical conditions for which traction is contraindicated. For example, patients with osteoporosis, degenerative joint disease, spinal fractures, joint hypermobility, or spinal root impingement, as well as patients who have undergone spinal fusion surgery, artificial disc placement, or who are pregnant should obtain approval from a clinician prior to performing home traction exercises. In addition, stretches should be discontinued if patients, regardless of background, experience pain, light-headedness, or numbness or tingling.

While at-home traction exercises are designed for immediate relief for a particular ailment, these should be performed alongside adopting healthy habits, including maintaining a straight posture, adequate nutrition, and plentiful exercise. Traction exercises are non-invasive, simple to learn, free, and reproducible, offering an excellent sustainable solution to treating pain or limited range of motion in a broad range of patients. As such, patients with a variety of forms of neck or back pain can and should continue to benefit from home traction exercises for better overall health.

References

1.        Jette, A. M., Smith, K., Haley, S. M., Davis, K. D. & Beattie, P. Physical therapy episodes of care for patients with low back pain. Phys. Ther. (1994). doi:10.1093/ptj/74.2.101

2.        Saunders, H. D. THE JOURNAL OF ORTHOPAEDIC AND SPORTS PHYSICAL THERAPY Lumbar Traction*. (1979).

3.        Kang, J. Il, Jeong, D. K. & Choi, H. Effect of spinal decompression on the lumbar muscle activity and disk height in patients with herniated intervertebral disk. J. Phys. Ther. Sci. (2016). doi:10.1589/jpts.28.3125

4.        Garg, P. Home Care Neck Traction for a Patient With Neck Pain and Cervical Radiculopathy Symptoms: A Case Report. J. Chiropr. Med. (2019). doi:10.1016/j.jcm.2018.11.006

5.        Self-Traction Techniques | My Doctor Online. Available at: https://mydoctor.kaiserpermanente.org/ncal/article/self-traction-techniques-506677.

6.        Thackeray, A., Fritz, J. M., Childs, J. D. & Brennan, G. P. The Effectiveness of mechanical traction among subgroups of patients with low back pain and leg pain: A randomized trial. J. Orthop. Sports Phys. Ther. (2016). doi:10.2519/jospt.2016.6238

Ankle sprains are one of the most common injuries experienced by athletes. Sprains can occur when the ligaments in the ankle become overstretched, torn, and/or inflamed. This may take place during jumping or running, or any instance when sudden changes of momentum acutely place excess strain on the joint. Without proper treatment, ankle sprains can lead to chronic weakness in the joint, as well as increased susceptibility to additional sprains. Therefore, athletes who have already had an ankle sprain are at increased risk for another during intense physical activity. One of the most prevalent types of ankle sprain is called an inversion ankle sprain, which occurs when a combination of inversion and plantar flexion turns the foot at an abnormal degree relative to the ankle. Despite the prevalence of inversion ankle sprains, many go undertreated, which in turn can lead to long-term joint instability and reoccurrence of the injury. To this end, one study discussed the use of high velocity, low amplitude (HVLA) chiropractic therapy in treating two young athletes with reoccurring inversion ankle sprains and joint instability.¹

The athletes included in the case study were a 17-year-old boy and a 13-year-old girl who participated in skateboarding/snowboarding and recreational soccer, respectively. Both patients would experience spontaneous ankle inversions during their recreational athletic activities, often with accompanying pain and ultimate sprain at the joint. Neither of them had previously attempted chiropractic intervention for their ankle instability, although the 17-year-old had attempted to use a stabilizing ankle brace with little success. Given that skeletally immature pediatric patients are notoriously difficult to treat for chronic ankle issues,² both patients were unlikely to experience complete resolution with typical therapeutic approaches.

To address their problems, Gillman applied HVLA chiropractic therapy to their spines, pelvises, and extremities, with a particular focus on the ankle. HVLA chiropractic techniques have been traditionally used to address lower and middle back pain, but can be applied to other joints as well. Though there is some variance within the approach itself, these adjustments typically involve applying a rapid thrust and pressure to a specific location to improve range of motion and increase the long-term stability of the compromised joint. It has been previously reported that high velocity, low amplitude techniques have significantly greater success as compared to placebo in patients with spinal issues;³ however, far less research has been done on its efficacy in other anatomical regions, particularly the extremities. For this reason, study author Dr. Scott Gillman’s approach could be viewed as largely experimental.

Notably, the study reported that both patients experienced abrupt resolution of their ankle instability following the application of HVLA chiropractic therapy. Such outcomes were highly unexpected considering the patient demographic and history of repetitive ankle trauma. Should these findings be replicable in a randomized trial, the data would suggest that chiropractic care could be considered as a suitable approach for the treatment of chronic ankle instability, particularly when it comes to high velocity, low amplitude techniques. Moreover, other experimental chiropractic techniques may also find application in the treatment of common sports injuries.

References 

¹ Gillman S. F. (2004). The impact of chiropractic manipulative therapy on chronic recurrent lateral ankle sprain syndrome in two young athletes. Journal of Chiropractic Medicine, 3(4), 153–159. https://doi.org/10.1016/S0899-3467(07)60103-7 

² Busconi, B. D., & Pappas, A. M. (1996). Chronic, painful ankle instability in skeletally immature athletes. Ununited osteochondral fractures of the distal fibula. The American Journal of Sports Medicine, 24(5), 647–651. https://doi.org/10.1177/036354659602400514 

³ von Heymann, W. J., Schloemer, P., Timm, J., & Muehlbauer, B. (2013). Spinal high-velocity low amplitude manipulation in acute nonspecific low back pain: a double-blinded randomized controlled trial in comparison with diclofenac and placebo. Spine, 38(7), 540–548. https://doi.org/10.1097/BRS.0b013e318275d09c 

            Back pain constitutes one of the most common non-emergent medical complaints: for example, it is estimated that around 80 percent of Americans will experience chronic back pain within their lifetime.¹ Despite the prevalence of back pain, it can be immensely difficult to treat; thus, preventative medicine remains the most effective approach. A number of factors can contribute to back pain, including occupation, age, and ergonomics. Perhaps one of the most pertinent contributing factors is body mass index. Ever since a 2010 study by Shiri et al. showed a direct correlation between obesity and back pain,² it has been well-established that being overweight is highly associated with back pain. At first glance, this finding may not seem surprising: after all, increased weight places greater strain on the musculoskeletal structure, including the muscles and joints of the spine. Yet some debate remains as to whether the association can be explained so simply.

            For example, in 2017, researchers at Cornell initiated an investigation to establish which specific back pain-causing conditions were associated with being overweight. Their findings were surprising: obesity was a predictor of only two of the four conditions studied, which were lower back pain and internal disc disruption.³ Spine degeneration (otherwise known as spondylosis) and neck problems were found to be unrelated to obesity. These results would suggest that other factors outside of body weight and mechanics are involved. Other studies, such as a 2015 one performed by Dafina Ibrahimi-Kaçuri et al., have shown that obesity may simply aggravate preexisting conditions instead of causing new ones.⁴ In fact, the authors concluded: “Obesity and age have no direct influence in back pain, but they could prolong healing.”⁴ Instead, they argue, factors such as physical workload are more likely to be the direct cause of chronic back pain.

            On the other hand, it is clear that obesity can substantially alter normal bodily mechanics, which in turn places undue strain on one’s back. For example, a cross-sectional study of obese women demonstrated that having increased weight in the lower abdomen changed individuals’ centers of gravity, shifting their pelvis forward and straining the vertebrae inward (a condition called hyperlordosis).⁵ Such drastic shifts in alignment could, over time, cause chronic pain. Moreover, researchers have also suggested that adipose tissue itself might trigger metabolic shifts, which may play as much a part in back pain as the physical burden of additional weight.⁶ It is thought that these accumulative factors may explain why individuals who are obese are highly susceptible to herniated discs and sciatica, as well as lumbar radicular pain.

            While it remains unclear whether obesity is a cause or simply an aggravating factor when it comes to chronic back pain, there is little doubt that having a normal body weight can help in the avoidance of severe back pain. This is therefore a factor that should be taken into consideration when it comes to the treatment of this common issue. Healthcare providers might therefore consider incorporating healthy lifestyle and weight loss plans into their treatment regimens for the management of chronic back pain in obese patients.

References

1. Urits, I., Burshtein, A., Sharma, M., Testa, L., Gold, P. A., Orhurhu, V., Viswanath, O., Jones, M. R., Sidransky, M. A., Spektor, B., & Kaye, A. D. (2019). Low Back Pain, a Comprehensive Review: Pathophysiology, Diagnosis, and Treatment. Current Pain and Headache Reports, 23(3), 23. https://doi.org/10.1007/s11916-019-0757-1

2. Shiri, R., Karppinen, J., Leino-Arjas, P., Solovieva, S., & Viikari-Juntura, E. (2010). The association between obesity and low back pain: a meta-analysis. American Journal of Epidemiology, 171(2), 135–154. https://doi.org/10.1093/aje/kwp356

3. Sheng, B., Feng, C., Zhang, D., Spitler, H., & Shi, L. (2017). Associations between Obesity and Spinal Diseases: A Medical Expenditure Panel Study Analysis. International Journal of Environmental Research and Public Health, 14(2), 183. https://doi.org/10.3390/ijerph14020183

4. Ibrahimi-Kaçuri, D., Murtezani, A., Rrecaj, S., Martinaj, M., & Haxhiu, B. (2015). Low back pain and obesity. Medical Archives (Sarajevo, Bosnia and Herzegovina), 69(2), 114–116. https://doi.org/10.5455/medarh.2015.69.114-116

5. Vismara, L., Menegoni, F., Zaina, F., Galli, M., Negrini, S., & Capodaglio, P. (2010). Effect of obesity and low back pain on spinal mobility: a cross sectional study in women. Journal of Neuroengineering and Rehabilitation, 7, 3. https://doi.org/10.1186/1743-0003-7-3

6. Rosen, E. D., & Spiegelman, B. M. (2014). What we talk about when we talk about fat. Cell, 156(1-2), 20–44. https://doi.org/10.1016/j.cell.2013.12.012

Thermotherapy is a form of heat-based treatment that has long been used in sports medicine and injury rehabilitation [1]. The physiological benefits of thermotherapy include decreased joint stiffness, increased soft tissue extensibility, augmented metabolism, and improved local circulation [1]. It can provide patients with analgesia in the regions where it is applied [1]. Thermotherapy can be easily administered in the form of compresses and hot bags [1]. Given these benefits, thermotherapy has been applied in the context of chiropractic care to treat mechanical musculoskeletal disorders. This article will investigate the observed efficacy of thermotherapy to evaluate whether heat-based treatment is an appropriate recourse in chiropractic care.

In the United States, low back pain is the most prevalent complaint cited by patients who seek chiropractic care [2]. Shakoor et al. conducted a randomized clinical trial to investigate how well thermotherapy can treat low back pain patients [3]. In the study, the treatment group received thermotherapy via short wave diathermy and non-steroidal anti-inflammatory drugs (NSAIDs), while the control group received placebo treatment and NSAIDs [3]. While the treatment group reported a significant improvement in their low back pain, the relative effects of the anti-inflammatory drugs compared to the thermotherapy are uncertain [3]. Another study (n = 87) that compared thermotherapy to cryotherapy and a control group reported similar results over the short-term [4]. However, the thermotherapy group also received naproxen, which, again, leaves the isolated efficacy of heat therapy uncertain [4]. A larger meta-analysis combined nine trials (n = 1,117) to identify the effect of thermotherapy on low back pain [5]. Many subjects with acute low back pain reported reduced pain in the short-term, but no long-term benefits of heat therapy were found [5].

The second most prevalent chiropractic concern in the US is neck pain [2]. Compared to low back pain, clinicians have studied the effects of thermotherapy on neck pain to a much lesser extent [2]. Hurwitz et al.’s study (n = 336) centered on manipulation and mobilization, but it also compared heat therapy to non-heated manipulation and non-heated mobilization, with and without electrical muscle stimulation [2]. At two weeks, participants receiving thermotherapy were more likely to report significantly lower pain levels than the other participants [2]. But by the end of the six-month-long experiment, the differences between the participant groups were clinically negligible, suggesting that, as with back pain, heat therapy may be limited to producing short-term benefits in neck pain patients [2]. A smaller 2012 study (n = 50) supports this claim [6]. After 14 days of either self-administered heat therapy or no additional treatment, patients in the former group reported lower pain intensity than the latter [6]. No differences were found between the groups in health-related quality of life, pressure pain threshold, or neck disability index [6].

Despite the somewhat promising effects of thermotherapy on low back pain and neck pain, rheumatoid arthritis (RA) is a chiropractic concern for which heat therapy may not be so successful [7]. A meta-analysis of seven studies, together covering the cases of 328 people, observed how hot packs, among other therapies, fared in treating RA patients [7]. The researchers measured how each treatment affected patients’ pain levels, range of motion, grip strength, medication intake, joint swelling, and hand function [7]. The study concluded that it is unclear whether thermotherapy is beneficial for individuals with RA [2].

In summary, thermotherapy is an attractive option within chiropractic care, as a non-invasive, non-pharmacologic, and cost-effective treatment for patients. Nonetheless, considering the limited literature concerning its ability to help neck pain and RA patients, among others, the technique may not be suitable as a primary treatment in those situations.

References

[1] N. C. O. Vargas e Silva, A. L. Rubio, and F. M. Alfieri, “Pain Tolerance: The Influence of Cold or Heat Therapy,” Journal of Chiropractic Medicine, vol. 18, no. 4, p. 261-269, December 2019. [Online]. Available: https://doi.org/10.1016/j.jcm.2019.03.002.

[2] E. L. Hurwitz et al., “A Randomized Trial of Chiropractic Manipulation and Mobilization for Patients With Neck Pain: Clinical Outcomes From the UCLA Neck-Pain Study,” American Journal of Public Health, vol. 92, no. 10, p. 1634-1641, October 2002. [Online]. Available: https://bit.ly/3hgywFO.

[3] M. A. Shakoor, M. S. Rahman, and M. Moyeenuzzaman, “Effects of deep heat therapy on the patients with chronic low back pain,” Mymensingh Medical Journal, vol. 17, no. 2, p. S32-S38, July 2008. [Online]. Available: https://bit.ly/3bcRGZa.

[4]M. Dehghan and F. Farahbod, “The Efficacy of Thermotherapy and Cryotherapy on Pain Relief in Patients with Acute Low Back Pain, A Clinical Trial Study,” Journal of Clinical and Diagnostic Research, vol. 8, no. 9, p. LC01-LC04, September 2014. [Online]. Available: https://doi.org/10.7860/JCDR/2014/7404.4818.

[5]S. D. French et al., “A Cochrane review of superficial heat or cold for low back pain,” Spine, vol. 31, no. 9, p. 998-1006, April 2006. [Online]. Available: https://doi.org/10.1097/01.brs.0000214881.10814.64.

[6]H. Cramer et al., “Thermotherapy self-treatment for neck pain relief—A randomized controlled trial,” European Journal of Integrative Medicine, vol. 4, no. 4, p. e371-e378, December 2012. [Online]. Available: https://doi.org/10.1016/j.eujim.2012.04.001.

[7] V. Welch et al., “Thermotherapy for treating rheumatoid arthritis,” Mymensingh Medical Journal, vol. 2002, no. 2, p. 1-50, April 2002. [Online]. Available: https://doi.org/10.1002/14651858.CD002826.

The Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study estimates that over one billion people had a migraine headache in 2016. This burden is significant, and migraines are ranked among the most common causes of “years of life lived with disability” (YLDs). Migraines caused 45.1 million YLDs globally in 2016, with the burden falling most heavily on women aged 15-49 years old. In this age group, migraines and tension-type headaches account for over ten percent of all YLDs.¹ The management of migraine is also difficult, due to an incomplete understanding of their mechanism.

Researchers have achieved major advancements in understanding the pathophysiology of migraines, which are now recognized as manifestations of nervous system dysfunction rather than mere vascular headaches; while changes in blood flow to the brain perhaps contribute to pain, they likely do not initiate it. Diverse clinical features (including premonitory symptoms, aura, nausea, and dizziness) demonstrate the complexity of the condition. At least 38 genetic loci have been associated with migraines, but their functions differ; it is highly likely that complex gene-environment interactions cause migraine headaches and therefore must be considered in their management.²

Stress, exacerbating medications, metabolic changes associated with diet and neuroendocrine function, and hormonal changes (especially those induced by pregnancy and menstruation) may all also play a role in stimulating migraines.² In some individuals, the attack frequency of episodic migraine can increase to the point of chronic migraine (at least 15 headache days per month for 3 months, with at least 8 of the headache days fitting the criteria for migraine headaches). Risk factors for chronification include overuse of acute migraine medication, obesity, depression, and stressful life events. Low socioeconomic and education statuses are associated with migraine chronification as well.³

Triptans and non-opioid analgesics (nonsteroidal anti-inflammatory drugs) are common medications used to treat migraines.² However, the overuse of acute migraine medication (analgesic intake on more than 15 days per month or triptan intake on more than 10 days per month) is considered to be likely the most important cause of migraine progression, and therefore their usage must be carefully monitored.³

Beta-blockers are used as a preventative measure to limit the frequency of migraine. Local anesthetics (with or without steroids) are also sometimes injected in headache centers as preventative measures, particularly in the regions of the occipital nerves.² Additional management options exist for those with chronic migraine: In 2010, the U.S. Food and Drug Administration approved Botox for the management of chronic migraine. The injection blocks the release of neurotransmitters implicated in perceptions of pain and has been shown to be an effective treatment, even for patients with concomitant medication overuse.⁴ Still, studies show that reducing medication overuse leads to significant migraine alleviation in chronic migraine patients.³

Because many people who experience migraines also report musculoskeletal issues like neck pain (reported by 75 percent of patients), there has been interest in incorporating chiropractic practices into neurological treatment plans. Harvard Medical School established the Osher Clinical Center (OCC) for Complementary and Integrative Therapies in 2007 at Brigham and Women’s Hospital, making it one of the first integrative medicine clinics at a tertiary care academic medical center. A 2019 case series published by Dr. Carolyn Bernstein and OCC researchers shared three cases demonstrating improvements in pain scores, increases in pain-free days, decreased medication usage, and decreased patient-reported anxiety/dysthymia with integrative approaches to treatment. The treatments included soft tissue therapies (including myofascial release, massage, and trigger point therapies), as well as spinal manipulation, which has been hypothesized to activate descending pain inhibitory pathways responsible for pain modulation.⁵

A 2019 systematic review that included six randomized clinical trials found that spinal manipulation may be an effective therapeutic treatment to reduce pain levels and slightly decrease migraine days. Larger-scale studies, however, are needed to further understand how chiropractic treatment may benefit those afflicted with migraine headaches.⁶

References

1. GBD 2016 Headache Collaborators. Global, regional, and national burden of migraine and tension-type headache, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016. Lancet Neurol. 2018;17(11):954-976. https://thelancet.com/journals/laneur/article/PIIS1474-4422(18)30322-3/fulltext
2. Charles A. The pathophysiology of migraine: implications for clinical management. Lancet Neurol. 2018;17(2):174-182.
3. May A, Schulte LH. Chronic migraine: risk factors, mechanisms and treatment. Nat Rev Neurol. 2016;12(8):455-464.
4. Escher CM, Paracka L, Dressler D, Kollewe K. Botulinum toxin in the management of chronic migraine: clinical evidence and experience. Ther Adv Neurol Disord. 2017;10(2):127-135.
5. Bernstein C, Wayne PM, Rist PM, Osypiuk K, Hernandez A, Kowalski M. Integrating chiropractic care into the treatment of migraine headaches in a tertiary care hospital: A case series. Glob Adv Health Med. 2019;8:2164956119835778.
6. Rist PM, Hernandez A, Bernstein C, et al. The impact of spinal manipulation on migraine pain and disability: A systematic review and meta-analysis. Headache. 2019;59(4):532-542.

While much of the attention surrounding cholesterol relates to its negative association with heart disease, the molecule plays a number of essential physiological roles in promoting the health of humans and a diverse array of life forms — even fossils nearly 600 years old have been found to contain this lipid.¹

Cholesterol, a waxy, light-colored fat, is an essential component in cell membranes. Flexible, porous plasma membranes surround every cell in the human body, and cholesterol helps maintain the membranes’ structure.² Furthermore, the chemical properties of cholesterol allow a diverse array of signaling proteins to associate with the cell membrane, allowing cells to communicate with each other. Therefore, cholesterol has implications for reproductive biology (through sperm activation), cancer (through oncogenic protein regulation), and numerous other fields.³ Cholesterol is needed to create steroid-based hormones, including testosterone and progesterone. Other hormones like aldosterone, key for kidney functioning, and cortisol, which activates the body’s stress response, also require cholesterol for their manufacturing. So too does vitamin D, which is present in few foods but is critical for the body’s ability to use calcium. Cholesterol also plays a notable role in the formation of bile acids, which help the body digest and absorb fats.⁴

Thus, cholesterol, cholesterol metabolites, and precursors of cholesterol are critical for routine and essential bodily functions,³ including other, less commonly cited roles. Cells in the lens of the human eye contain enormously high levels of cholesterol, and this cholesterol is immensely important: those with genetic disorders affecting the cholesterol synthesis pathway often have cataracts, and cholesterol-lowering drugs have been associated with cataract-like effects in animals. Many studies have shown that statins that block cholesterol synthesis also are associated with cataracts.⁵

Unlike other parts of the body, the eye lens is avascular — not connected to the bloodstream — and high concentrations of cholesterol are not abnormal.⁵ Excess cholesterol in the bloodstream, however, can lead to atherosclerosis, or the formation of plaques in the walls of blood vessels. This can weaken the blood vessels, cause the formation of blood clots, and result in heart disease, stroke, or damage to the kidneys and intestines.⁴ Still, the impact of cholesterol is not fully explained by its quantity; the way it is transported matters, too. There are five major transporter proteins (called lipoproteins, which allow the lipid-soluble cholesterol to flow through the water-soluble bloodstream). While low-density lipoprotein (LDL) particles deliver cholesterol to tissues and are rich in pure cholesterol, high-density lipoprotein (HDL) particles help remove cholesterol from circulation, returning it to the liver.²

It is becoming increasingly clear that a full lipid profile test is critical for assessing cardiovascular disease (CVD) risk. If the proportion of HDL to LDL cholesterol is high, risks of atherosclerosis may be lower, even if someone has high total cholesterol.⁴ This is just one example of the complex considerations surrounding cholesterol management. The impact of cholesterol on bone health is another example of this. While studies in animals and cell cultures suggest that the cholesterol-lowering effects of some statins benefit bone metabolism, this relationship remains unclear in humans. It is widely known that cholesterol influences hematopoietic stem cell proliferation, driving the production of blood cells (a crucial life process) but this can also potentially contribute to the development of atherothrombosis (the accumulation of lipids and other materials that can form a clot in the arterial wall).⁶

Cholesterol performs many critical roles in the human body; still, its confounding detrimental health impact means that much focus has been placed on limiting its dietary intake.² Historically, nutrition guidelines for reducing CVD risk have included explicit limitations for dietary cholesterol. However, the American Heart Association and American College of Cardiology have more recently eliminated specific targets because of the complexity of the relationship between CVD risk and cholesterol.⁷ Roughly 80 percent of cholesterol is created by the human body itself,² a fact that serves as testament to its importance.

References 

1. Davis J. Fat molecules preserved in a 558-million-year-old fossil help settle decades-old debate. National History Museum. Published 2018. https://www.nhm.ac.uk/discover/news/2018/september/fat-molecules-preserved-in-a-558-million-year-old-fossil-help-se.html  

2. Corliss J. How it’s made: Cholesterol production in your body. Harvard Health Publishing. Published 2019. https://www.health.harvard.edu/heart-health/how-its-made-cholesterol-production-in-your-body  

3. Tabas I. Cholesterol in health and disease. J Clin Invest. 2002;110(5):583-590. 

4. Mulryan C. The role of cholesterol. Independent Nurse. Published 2012. https://www.independentnurse.co.uk/clinical-article/the-role-of-cholesterol/63612/  

5. Widomska J, Subczynski WK. Why is very high cholesterol content beneficial for the eye lens but negative for other organs? Nutrients. 2019;11(5):1083. 

6. Yin W, Li Z, Zhang W. Modulation of bone and marrow niche by cholesterol. Nutrients. 2019;11(6):1394. 

7. Carson JAS, Lichtenstein AH, Anderson CAM, et al. Dietary cholesterol and cardiovascular risk: A science advisory from the American heart association. Circulation. 2020;141(3):e39-e53.  

The link between the digestive and nervous systems, often termed the gut-brain axis (GBA) [1-4,6,7], consists of three parts—the enteric nervous system (ENS), “a collection of neurons in the gastrointestinal tract”; the central nervous system (CNS), comprising the brain and spinal cord; and the autonomous nervous system, which transfers information from the gut to the brain and vice versa [6]. These bidirectional interactions control “the motility, exocrine and endocrine secretions, and microcirculation of the gastrointestinal (GI) tract” [6], while also regulating the immune and inflammatory processes [4,5,6]. Researchers also posit that the GBA “supports and influences mood, cognitive function, and motivated behavior” [1].

One of the major indicators of gut health is its vast and complex microbial ecosystem, known as the gut microbiota [3]. Consisting mostly of bacteria, the gut microbiota plays a vital role in the bidirectional interactions that occur within the GBA [3]. For example, “it interacts with [the] CNS by regulating brain chemistry and influencing neuro-endocrine systems associated with stress response, anxiety, and memory function” [2]. Other functions include maintaining normal mucosal immune activity, “protecting against pathogens, participating in the intake of nutrients from the diet, metabolizing certain drugs and carcinogens, and influencing the absorption and distribution of fat” [3].

Studies indicate that disruption of the microbiota, known as dysbiosis, “perturbs host functions and, in some cases, causes the expression of overt and serious diseases such as IBD (inflammatory bowel disease) and Clostridium difficile colitis” [3]. According to Collins et al, “evidence is emerging of dysbiosis in patients with IBS (irritable bowel syndrome)” [3]. Dysbiosis has also been shown to “alter brain function and trigger the development of psychiatric disorders such as depression, schizophrenia, and Parkinson’s disease” [1].

Similarly, stress has been shown to produce adverse effects on the gut, and exacerbate the expression of certain diseases, such as IBD, and functional gastrointestinal disorders [7]. Additionally, “disorders of the enteric nervous system may result in motor, secretory, and inflammatory and immunologic dysfunction of the gut” [6]. However, some researchers postulate that “psychiatric and/or neurological diseases might be treated by using special probiotic bacteria,” special microbes (bacteria or yeast) which have been shown to improve the function of organs, the immune system, and the CNS [2,3].

Although the link between the digestive and nervous systems is directly related to overall health, “much remains to be elucidated with regard to the mechanism and impact of the interaction between the nervous system and the gastrointestinal system” [1]. More research is needed to determine the extent to which gut health influences the rest of the body and may be utilized to help treat certain conditions [1,6].

References 

1. Arneth, B. M. (2018). Gut-Brain Axis Biochemical Signaling from the Gastrointestinal Tract to the Central Nervous System: Gut Dysbiosis and Altered Brain Function. Postgraduate Medical Journal. DOI: 10.1136/postgradmedj-2017-135424 

2. Carabotti, M., Scirocco, A., et al. (2015). The Gut-Brain Axis: Interactions Between Enteric Microbiota, Central and Enteric Nervous Systems. Annals of Gastroenterology, 28(2), 203–209. PMID: 25830558. Available: link

3. Collins, S. M., & Bercik, P. (2009). The Relationship Between Intestinal Microbiota and the Central Nervous System in Normal Gastrointestinal Function and Disease. Gastroenterology, 136(6), 2003–2014. DOI: 10.1053/j.gastro.2009.01.075 

4. Costa, M., Brookes, S., et al. (2000). Anatomy and Physiology of the Enteric Nervous System. GUT, 47, 15–19. DOI: 10.1136/gut.47.suppl_4.iv15 

5. Furness, J. B. (2012). The Enteric Nervous System and Neuro-gastroenterology. Nature Reviews. Gastroenterology & Hepatology, 9(5), 286–294. DOI: 10.1038/nrgastro.2012.32 

6. Goyal, R. K., & Hirano, I. (1996). The Enteric Nervous System. New England Journal of Medicine, 334, 106–115. DOI: 10.1056/NEJM199604253341707 

7. Van Oudenhove, D. L. K., Tack, J., et al. (2004). Central Nervous System Involvement in Functional Gastrointestinal Disorders. Best Practice & Research Clinical Gastroenterology, 18(4), 663–680. DOI: 10.1016/j.bpg.2004.04.010