Link found between chronic headache and back pain

A review of 14 studies found that people with persistent headache or back pain were twice as likely to experience the other disorder as well.

Chronic headaches and persistent back pain are both debilitating conditions. New findings suggest a link between the two, potentially charting a new course for more effective treatment.

Chronic headaches and back pain both appear in the top five causes of years lived with disability. Healthcare professionals often treat the conditions separately, but there is a theory that in some people, they appear together. Therefore, treating both as one disorder may provide better results.

Up to 4% of individuals in the global adult population have headaches on 15 or more days of every month, according to the World Health Organization (WHO).

Meanwhile, about 80% of adults experience low back pain at least once in their lifetime, according to the National Institute of Neurological Disorders and Stroke, and approximately 20% of these people go on to develop chronic low back pain.

In 2013, a German study found a link between low back pain and both chronic migraine and chronic tension-type headaches.

Now, researchers from the University of Warwick, United Kingdom, appear to have found an even stronger association.

Double the odds

Appearing in the Journal of Headache and Pain, their review involved 14 studies with a range of sample sizes. The smallest study included 88 participants, while the largest involved 404,206 individuals.

One type of headache and a particular back pain disorder were the focus: chronic headaches and persistent low back pain. The team notes the definitions of these conditions, describing the former as headaches that occur on the majority of days for a minimum of 3 months and the latter as pain “between the bottom of the rib cage and the buttock creases” for the same period.

The review found that all the studies shared a similar positive association between the two conditions. However, the odds of experiencing both conditions varied widely between the studies from less than twice as likely to eight times as likely.

This meant that the researchers were unable to pool the data in a combined statistical analysis. However, Prof. Martin Underwood notes, “[i]n most of the studies, we found that the odds were about double — either way, you’re about twice as likely to have headaches or chronic low back pain in the presence of the other.”

For people experiencing migraine ⁠— the third most prevalent illness in the world ⁠— the link was even stronger.

A few limitations exist, namely that inconsistent study designs and populations and varying definitions of the disorders may have weakened the quality of the results.

Still, the findings are “very interesting,” notes Prof. Martin Underwood, from Warwick Medical School, “because typically these have been looked at as separate disorders and then managed by different people.”

“But this makes you think that there might be, at least for some people, some commonality in what is causing the problem.”

Combining treatments

The researchers are not yet sure of the potential shared cause, but they have some theories. One, explains Prof. Underwood, is that there may be “an underpinning biological relationship” in some people with headaches and back pain.

“There may be something in the relationship between how people react to the pain,” he says, “making some people more sensitive to both the physical causes of the headache, particularly migraine, and the physical causes in the back, and how the body reacts to that and how you become disabled by it.”

Such a cause could be a target for treatment. In fact, the team thinks that a joint approach may be best.

Right now, drugs are available to treat chronic headaches. Some people try a range of holistic remedies too. Back pain, meanwhile, may require a combination of exercise and psychological therapy.

Ensuring that people with both disorders receive appropriate support and management techniques could well help their quality of life. A combined treatment method could also provide a financial benefit by reducing the number of medication prescriptions.

“There is a need for doctors and other healthcare professionals to think that when treating one issue, [they should] ask about the other and tailor the treatment accordingly.”

Prof. Martin Underwood

“For future research, there’s probably work that needs to be done to understand what the underlying mechanisms behind this relationship are,” he adds.

Man having a back pain over gray background

Onion & Garlic Vs Breast Cancer

Onions and garlic may protect against breast cancer

New research examines the consumption of onion and garlic among women in Puerto Rico and suggests that the vegetables can significantly reduce the risk of breast cancer.

Onions and garlic are part of the allium genus, along with leeks, chives, and hundreds of other species.

Rich in flavor, with a strong, pungent kick, these “feisty” vegetables may also be able to fight off diseases, such as diabetes, heart disease, and cancer, according to emerging evidence.

In regards to cancer, several studies have specifically explored the links between onion and garlic consumption and the risk of colorectal, stomach, and prostate cancers.

Overall, these studies have found that the more of these vegetables that people consume, the lower their risk of developing these cancers.

However, less extensive research has gone into the link with breast cancer, say researchers led by Gauri Desai, a doctoral candidate in epidemiology at the University at Buffalo (UB), part of The State University of New York.

So, Desai and the team set out to investigate this topic further, looking at a population of women in Puerto Rico. The reasons for choosing this population were twofold. Firstly, “Puerto Rico has lower breast cancer rates, compared to the mainland [United States], which makes it an important population to study,” explains Desai.

Secondly, a condiment called “sofrito,” which consists largely of garlic and onion, is a traditional Puerto Rican sauce that is widely consumed across the island.

The researchers published the results of their findings in the journal Nutrition and Cancer.

Studying onions, garlic, and cancer risk

Desai and the team used hospital and clinic records to identify 314 women aged between 30 and 79 who had breast cancer between 2008 and 2014. The researchers also included 346 control participants who were matched based on age and residential area.

nonmelanoma skin cancer. The researchers used a food frequency questionnaire to enquire about dietary patterns and total onion and garlic intake, which included sofrito consumption.

The team employed unconditional logistic regression to examine the association between onion and garlic intake and breast cancer occurrence, adjusting for factors such as age, education, family history, body mass index, smoking status, and others.

Sofrito linked to 67% lower breast cancer risk

The researchers found an inverse association between moderate and high total onion and garlic consumption and breast cancer cases, compared with low consumption of these vegetables.

Their findings were consistent after the researchers had stratified the results according to menopausal status, suggesting that “High onion and garlic consumption is protective against breast cancer in [the studied] population.”

Specifically, the authors write, “Sofrito intake, when examined alone, was inversely associated with breast cancer; for those consuming sofrito more than once/day, there was a 67% decrease in risk, compared to never consumers.”

“We found that among Puerto Rican women, the combined intake of onion and garlic, as well as sofrito, was associated with a reduced risk of breast cancer.”

Gauri Desai

“Studying Puerto Rican women who consume a lot of onions and garlic as sofrito was unique,” Desai adds, referring to one strength of the research.

Why might onions, garlic lower cancer risk?

Study co-author Jo Freudenheim, Ph.D., chair of epidemiology and environmental health at UB, also comments on the uniqueness of the study, saying, “There is very little research on breast cancer in Puerto Rico.”

“This study was a collaboration between my colleagues here at UB and at the University of Puerto Rico to help us understand why rates there are lower than in the rest of the U.S., and why rates there are continuing to increase, while they are decreasing in the rest of the [U.S.].”

Although the study was observational and cannot explain the mechanisms behind the findings, the researchers suspect that the flavonols and organosulfur compounds abundant in onions and garlic may be responsible for the anticancer effects.

In particular, the S-allylcysteine, diallyl disulfide, and diallyl sulfide in garlic and the alk(en)yl cysteine sulphoxides in onions have shown “anticarcinogenic properties in humans, as well as in experimental animal studies,” says Dr. Lina Mu, an associate professor of epidemiology and environmental health at UB and the study’s senior author.

Some study limitations

However, the authors also recognize some limitations to their research. For instance, they write, “The size of the study was small, particularly for analyses stratified on menopausal status.”

Secondly, the number of people who had never consumed garlic or onion was too small to use as a reference group. Therefore, the low exposure group still consumed some onion and garlic.

For this reason, say the researchers, the results “may have underestimated the true association between garlic and onion intake and breast cancer.”

“Furthermore, there is not a standardized recipe for sofrito, a condiment which is frequently homemade and therefore varies at least somewhat in recipe from person to person,” add the authors. “Hence, we were also not able to estimate the amount of onion and garlic in sofrito.”

“Although the recipe for sofrito varies to some extent, other ingredients, such as bell peppers, tomatoes, cilantro, and black pepper are usually added. Since we did not adjust our models for these ingredients, we cannot be sure that our results were due to the sole effect of onions and garlic.”