Dr. Sharma's Obesity Notes

Regular readers will appreciate the importance that I have given to pain both as a driver and consequence of weight gain as well as a barrier to treatment.

Just how closely obesity and pain are associated is now documented by Arthur Stone and Joan Broderick from Stony Brook University, NY, in a paper just published in OBESITY.

This study is based on a Gallup ‘poll’ of 1,062,271 randomly selected US individuals surveyed between 2008 through 2010.

BMI and pain yesterday were reliably associated (even when adjusted for a wide range of demographic variables): the overweight group reported 20% higher rates of pain than Low-Normal group, 68% higher for Obese I group, 136% higher for Obese II group, and 254% higher for Obese III group.

All of the tests of association between the pain conditions and BMI groups were significant, with the strongest association for the knee and leg condition.

The association held for both men and women but in women, the trend to more pain as BMI increases was steeper than in men.

The association between BMI and pain increases moving from the younger categories to the older categories; for those in the Obese III group, the odds ratio for the youngest group is 1.72 compared with a ratio of 3.79 for those in the highest age group.

As the authors note,

“The association is robust and holds after controlling for several pain conditions and across gender and age. The increasing BMI-pain association with older ages suggests a developmental process that, along with metabolic hypotheses, calls out for investigation.”

Despite the possible limitations due to the nature of the survey (telephone, self-reported height and weight and pain levels, etc.), the relationship between higher weight and pain is striking.

Assessing for pain (the 2nd ‘M’ or ‘Mechanical’) should be routine part of any exam for obesity and may have to be tackled in any obesity management program.

AMS
Edmonton, Alberta

Stone AA, & Broderick JE (2012). Obesity and pain are associated in the United States. Obesity (Silver Spring, Md.), 20 (7), 1491-5 PMID: 22262163

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Today’s post is another excerpt from “Best Weight: A Practical Guide to Office-Based Weight Management“, recently published by the Canadian Obesity Network.

This guide is meant for health professionals dealing with obese clients and is NOT a self-management tool or weight-loss program. However, I assume that even general readers may find some of this material of interest.

CHRONIC PAIN CONDITIONS

Any condition that leads to chronic pain can contribute to obesity by increasing physiological and psychological stress. Pain also makes exercise more difficult to undertake and enjoy.

Osteoarthritis and Back Pain

Obesity is commonly associated with musculoskeletal pain and osteoarthritis, resulting in functional and motor limitations. Obese patients usually move more slowly, are less flexible and feel pain when performing tasks at floor level. There is a strong association between knee osteoarthritis and obesity. Degenerative arthritis resulting from chronic trauma associated with excess body weight develops primarily in weight-bearing joints such as the knee and ankle. However osteoarthritis can also be seen in non-weight-bearing joints, suggesting a systemic inflammatory response. Excess body weight is also closely related to lower back pain. Both static and compressive loading may damage the integrity of intervertebral discs. Increased biomechanical force can also cause muscle sprain and ligament strain.Sleep disorders are very prevalent among obese people. Obstructive sleep apnea is the most common disorder, but disturbed sleep may also be due to primary insomnia, or insomnia secondary to medications, medical or psychiatric disorders.

The presence of significant pain can promote immobility, leading to loss of muscle mass and reduced cardiopulmonary fitness. This can precipitate psychological and metabolic changes that promote further weight gain.

Patients with painful joints may benefit from water-based (non-weight-bearing) exercise and may require pain management before embarking on a weight-loss program. Obese patients requiring joint-replacement surgery are generally advised to lose weight (often in unrealistic amounts) before surgery, but this is very difficult if they are already partially immobilized by pain.

To complicate matters further, most commercial gyms are ill-equipped to handle the needs of obese clients, many of whom cannot go from lying down on the floor to standing up without assistance. Step classes and aerobics classes are in many cases ill-advised, and exercise machines and weight benches are not usually designed for obese users.

Fibromyalgia

Obesity is often associated with fibromyalgia, a common disorder characterized by fatigue, pain, stiffness in the trunk and extremities and a number of specific tender points. Fibromyalgia is more common in women than in men and is frequently accompanied by sleep disorders. Treatment of fibromyalgia may increase a patient’s ability to be physically active, and exercise has been shown to reduce the severity of fibromyalgia symptoms over time. As with severe osteoarthritis, starting with joint-sparing exercises may be prudent.

© Copyright 2010 by Dr. Arya M. Sharma and Dr. Yoni Freedhoff. All rights reserved.

The opinions in this book are those of the authors and do not represent those of the Canadian Obesity Network.

Members of the Canadian Obesity Network can download Best Weight for free.

Best Weight is also available at Amazon and Barnes & Nobles (part of the proceeds from all sales go to support the Canadian Obesity Network)

If you have already read Best Weight, please take a few minutes to leave a review on the Amazon or Barnes & Nobles website.

Among the many aches and pains commonly associated with excess weight, the increased prevalence and severity of migraines in patients with obesity is perhaps the least well known.

Not only do migraines appear to be more common in patients with excess weight but there is also evidence that people with severe obesity are likely to have more severe migraines than individuals with normal weight.

There are a number of plausible psychological and physiological mechanisms that could explain this relationship. The former include the finding that pathological pain processing, catastrophising and sensitivity has been associated with excess weight. The latter is supported by recent evidence that pro-inflammatory molecules that are increased in obese individuals can act as pain mediators in neurovascular inflammation.

These finding certainly raise the question whether weight loss can reduce the frequency and/or intensity of migraines.

This question was now addressed by Dale Bond and colleagues from Providence, Rhode Island, in a paper just published in NEUROLOGY.

The researchers prospectively assessed 24 patients (88% female, BMI 47) who had migraine according to the ID-Migraine screener before and 6 months after bariatric surgery.

Post-surgical weight loss was associated with a significant reduction in number of headache days from 11 to 7 in the 90 days preceding each assessment. Patients, who lost the most weight, also had the greatest odds of experiencing a more than 50% reduction in headache days. Furthermore, the number of patients reporting moderate to severe disability due to migraines decreased from 12 (50.0%) before surgery to 3 (12.5%) after surgery. While patients also reported significant improvement in depression (average PHQ-9 scores reduced from 8.8 to 4.3), the changes in mood were not predictive of the improvements in migraines.

This study certainly supports the hypothesis that migraine frequency and severity in severely obese patients reduces with surgical weight loss.

On the other hand, before jumping to overly enthusiastic conclusions, it may be prudent to note that this study did not assess or discuss the possibility that the lifestyle changes associated with surgery may simply have reduced exposure to many of the nutritional and lifestyle triggers of migraines (e.g. certain foods such as fruits, onions, chocolate, nuts, cheese, sugar, caffeine, alcohol or red wine as well as stress or physical exertion).

I guess it would take a prospective trial with careful assessment of these migraine triggers (or at least a control group of weight-stable patients who make the same dietary and lifestyle changes) to determine how much of this finding is explained by weight loss rather than simply by lifestyle change following surgery.

Nevertheless, I do wonder if any of my readers have observed similar changes in headache frequencies with changes in body weight or environmental triggers unrelated to weight loss.

AMS
Edmonton, Alberta

Bond DS, Vithiananthan S, Nash JM, Thomas JG, & Wing RR (2011). Improvement of migraine headaches in severely obese patients after bariatric surgery. Neurology, 76 (13), 1135-8 PMID: 21444898

On most days, our obesity clinic could easily be confused with an orthopedic clinic given the sheer number of patients who present with severe pains in their backs, knees, hips, and ankles – often to the point of immobility.

It turns out (perhaps not surprisingly) that today, obesity and knee osteoarthritis are among the most frequent chronic conditions affecting Americans aged 50 to 84 years – my guess is that these conditions are no less frequent among Canadians.

Given the high prevalence of both obesity and knee osteoarthritis and their very significant impact on quality of life, Losina and a team of researchers from Harvard, Boston University, Chapel Hill, Yale and the University of Sydney undertook the rather momentous task of estimating the impact of these conditions on morbidity and mortality in older Americans. Their results were now published in the Annals of Internal Medicine.

The researchers based their analyses on U.S. Census and national obesity data with estimated prevalence of symptomatic knee osteoarthritis, whereby they assigned the US population aged 50 to 84 years to four subpopulations: nonobese without knee osteoarthritis (reference group), nonobese with knee osteoarthritis, obese without knee osteoarthritis, and obese with knee osteoarthritis.

They then used a computer simulation model (The Osteoarthritis Policy Model) to estimate quality-adjusted life-year losses due to knee osteoarthritis and obesity and to determine health benefits of reducing obesity prevalence to levels observed a decade ago.

It turns out that the estimated total losses of per-person quality-adjusted life-years ranged from around 2 years in nonobese persons with knee osteoarthritis to about 3.5 years for persons affected by both conditions. Although these numbers may not sound shocking, they actually represent 10% to 25% of the remaining quality-adjusted survival of persons aged 50 to 84 years.

When calculated for the entire US population in that age range, this amounts to a staggering 86 million quality-adjusted lost to these conditions.

The researchers also calculate that reversing obesity prevalence to levels seen 10 years ago would avert just over 110,000 total knee replacements – so reducing obesity (even to where it was just 10 years ago) could indeed save a substantial number of knees.

What the paper of course does not disclose is how exactly such a reversal in obesity rates could possibly be achieved.

Clearly, the impact of weight loss on knee (and other) pain that we see in our clinic is often dramatic, but achieving weight loss for someone who is already immobilised by knee (or other) pain is definitely a challenge.

I’d certainly love to hear from my readers on how knee (or other) pain has affected their weight and whether or not they have experienced improvement in their knee (or other) pain with weight loss.

AMS
Edmonton, Alberta

Losina E, Walensky RP, Reichmann WM, Holt HL, Gerlovin H, Solomon DH, Jordan JM, Hunter DJ, Suter LG, Weinstein AM, Paltiel AD, & Katz JN (2011). Impact of obesity and knee osteoarthritis on morbidity and mortality in older americans. Annals of internal medicine, 154 (4), 217-26 PMID: 21320937

As blogged before, overweight and obese patients frequently present with fibromyalgia, characterized by chronic pain, fatigue and depressed mood.

A paper by Akiko Okifuji from the University of Utah, Salt Lake City, just published in the Journal of Pain, examines the relationship between fibromyalgia and obesity in pain, function, mood, and sleep.

The study examines the impact of obesity on hyperalgesia, symptoms, physical abilities, and sleep in 215 fibromyalgia patients, who also underwent tender point examination, physical performance testing, and 7-day home sleep assessment.

Almost 50% of participants were obese and an additional 30% were overweight.

Obesity was positively related to greater tender point sensitivity, reduced physical strength and lower-body flexibility, shorter sleep duration, and greater restlessness during sleep.

The results confirmed that obesity is a prevalent comorbidity of fibromyalgia and the authors suggest that weight management may need to be incorporated into treatments.

In the paper, Okifuji and colleagues also discuss several potential mechanisms linking obesity to fibromyalgia including alterations in the endogenous opioid system, the endocrine system, and systemic inflammation, whereby adipose-tissue derived cytokines may enhance central sensitization.

Clinicians should be aware of the relationship between excess weight and fibromyalgia, which can often pose an important contributor to weight gain and a major barrier to weight management.

AMS
Edmonton, Alberta

Okifuji A, Donaldson GW, Barck L, & Fine PG (2010). Relationship Between Fibromyalgia and Obesity in Pain, Function, Mood, and Sleep. The journal of pain : official journal of the American Pain Society PMID: 20542742