Continuous exercise versus high intensity aerobic exercise for COPD patients

In the December 2009 issue of Thorax, a group of researchers conducted a “meta-analysis” (defined below) of studies that examined whether there were differences in COPD patient physical conditioning when exercising at a constant, moderate level of intensity versus a shorter, but more intense level of aerobic exercise. Their conclusion – there is no meaningful difference in conditioning benefits between the two exercise approaches for COPD patients. (Beauchamp EK, et al. Interval versus continuous training in individuals with COPD - a systematic review. Thorax published online December 8, 2009. doi: 10.1136/thx.2009.123000).

What’s odd about this conclusion is that in both healthy adults and those who have been diagnosed with heart disease, interval training has been shown to deliver notably higher conditioning benefits. This conclusion was recently reaffirmed by a review article that appeared in the January/February 2010 issue of the Journal of Cardiopulmonary Rehabilitation and Prevention (Kemi OJ, Wisloff U. High-Intensity Aerobic Exercise Training Improves the Heart in Health and Disease. JCRP. 2010; 30:2-11).

Despite their differing conclusions about whether one form of aerobic exercise is better than the other, both sets of researchers are clear in their statements that both constant, moderate level exercise and high-intensity interval exercise delivers powerful conditioning benefits (for COPD patients, heart disease patients, and healthy adults).

Before diving into the details, let us first explain the term meta-analysis. At times, researchers will compile and analyze data from a range of studies that examine a similar subject matter in order to determine whether there are broader conclusions to draw from collective body of work on the subject matter. This analysis is referred to as a meta-analysis. In conducting a meta-analysis, the researchers first cull through the various published studies to eliminate those that in their opinion do not pass muster in terms of sample size, study construction, study duration and other influencing factors. The data from the remaining studies after this weeding out process are then evaluated for broad similarities. In the Thorax article, 8 studies made it into the meta-analysis.

As mentioned above, the basic issue examined in both articles is whether or not people benefit more from participating in aerobic activity at a constant, moderate level or from high intensity interval aerobic activity. Typically, in constant-moderate aerobic exercise regimens, subjects work out at a level that is between 50-70% of their maximum peak exertion (different researchers use different measures to determine this level , one common measurement method is called VO2 max – the maximum amount of oxygen a person uses during one minute of intense aerobic exercise). In constant-moderate aerobic exercise studies, the researchers first establish the maximum peak exertion threshold for each patient. With this information in hand, the researchers do subsequent testing where they reduce the exercise intensity (typically done by lowering resistance/incline/speed of various cardiovascular exercise equipment) until the subject can maintain 50-70% of their maximum peak threshold for an extended period of time (typically 30-40 minutes).

By contrast, high-intensity interval aerobic exercise typically involves repeated short segments of exercise at 90-95% of the subject’s maximum peak exertion level (anywhere from 30 seconds to 4 minutes) intermixed with lower intensity aerobic exercise segments (at 30%-50% of maximum exertion) in between for similar amounts of time. So in a 20-30 minute interval session, a patient will perform multiple segments of 1-3 minutes high-intensity aerobic activity alternating with multiple segments of 2-4 minute low-intensity aerobic activity.

Some researchers believe that the interval approach tends to build higher levels of conditioning because the subjects are pushing their heart, lungs, circulation system and muscles to handle higher loads of activity in comparison to constant-moderate aerobic exercise. Even the Thorax researchers noted, “In healthy subjects and in those with CHF (congestive heart failure), high-intensity interval training has been shown to be as effective or superior to continuous training with respect to effects on physiological markers of exercise capacity.”

We think this point of view makes intuitive sense but for some reason this phenomenon is not demonstrated consistently in COPD patients. One suggestion by the researchers in the Thorax article is that COPD patients (who in general are not regular exercisers) see such huge gains in physical conditioning in pulmonary rehabilitation from any form of aerobic exercise that the relative performance of one type of aerobic exercise versus another is minimized.

But the Thorax researchers also suggest that interval training might be a valuable option in pulmonary rehab for COPD patients in that some patients adhere to their exercise schedule better when they can mix up the time/duration/intensity of exercise (the variety makes it more interesting, and interval training takes less time).

In noting the potential value of both forms of aerobic training, the researchers conclude, “…evidence from the eight trials included in this review suggests that there are no differences between the effect of interval and continuous training on improving exercise capacity and health-related quality of life in individuals with COPD. Interval training may therefore be considered as a training option or complement to continuous exercise in patients unable to tolerate high-intensity continuous exercise.”

In our opinion, if you are interested in mixing up your aerobic exercise routine, it is worth considering high intensity interval training. The research is clear that it at least provides the same conditioning benefits as constant-moderate level training. For moderate to severe COPD patients, you should consult your physician first to determine if interval training is appropriate in your situation. We also highly recommend that you consult a personal trainer at a fitness center or a respiratory therapist in your pulmonologist’s office or pulmonary rehab clinic to help create an "starter" interval program that is right for your level of current conditioning.

New Danish Study Reaffirms Benefit of Long-Term Pulmonary Rehab

In the January/February 2010 issue of the Journal of Cardiopulmonary Rehabilitation and Prevention, Danish researchers led by Thomas Ringbaek reported that COPD patients who continued a maintenance pulmonary rehabilitation for 1 year after graduating a traditional 7 week rehab program enjoyed higher, sustained physical capacity and conditioning (Ringbaek T, et al. Long-term Effects of 1-Year Maintenance Training on Physical Functioning and Health Status in Patients With COPD. J Cardiopulm Rehabil Prev. 2010 Jan-Feb;30(1):47-52). Normally, we'd provide you a link to the free, full-text of the study so you can read it for yourself but alas this one you have to pay the journal publisher to read L

This is not the first study to show such results but it is a helpful reminder of the value of beginning and continuing a physical exercise program if you suffer from chronic shortness of breath or have a lung condition such as COPD. As the researchers noted, "Our data support the notion that poor adherence to exercise at home (and supervised training if offered) is the most important reason for the declining effect of pulmonary rehabilitation. Adherence to home exercise after rehabilitation is rarely reported."

In other words, far too often patients who've achieved notable physical conditioning improvements during a pulmonary rehab programs see those benefits diminish or disappear over time because they don't stick with it. It's a frustrating situation for practitioners who invest a lot of time and effort over the course of a 6-8 week pulmonary rehab program to instill in patients the things they can and should do to improve how they feel and live. But alas, many (no strike that, most) patients don't continue on.

The research team here sought to provide a solution to this problem by offering once a week maintenance exercise sessions for the first six months after the formal 7 week rehab program and then once a month sessions for the six months after that. The group that completed the initial 7 week program and continued with the research-team designed maintenance program (deigned the Maintenance group by the researchers) saw significantly higher levels of conditioning compared to those who completed the initial 7 week program and were sent on their way to fend for themselves with the advice to keep up the good work (denoted as the Control group in the study).

Both groups experienced huge jumps in a test called the Endurance Shuttle Walk Test (ESWT) as a result of the 7 week rehab program. In this test, patients are asked to walk at a constant speed at 85% of their physical capacity (85% of their VO2 predicted maximum). From the researchers published graphs, it appears both groups saw their physical capacity rise approximately 70%-80% from their pre-rehab test to their post-rehab ESWT. The power of pulmonary rehab in action.

The Maintenance group saw further, but modest, improvement in ESWT over the next year after the formal rehab program but the Control group saw their rehab program gains erode significantly in the same time span. The researchers conclude, "We conclude that MT (maintenance training) for 1 year following a 7-week pulmonary rehabilitation program improved physical capacity…". It should be noted that the researchers also evaluated improvements in quality of life survey results and future hospitalizations in the study and in both cases did not find significant differences between the two groups.

The researchers wrap up their paper by encouraging further research into why the majority of COPD patients do not maintain exercise after a rehab program. They cite lack of motivation/supervision as one likely answer and breathing exacerbation events as another (an exacerbation is essentially a shortness of breath attack that often lands a patient back in the hospital).

They are probably right on both counts – but we think the real lesson is clear. The more people are given access to the principles and practices of pulmonary rehab and the more places these people can receive guidance and support for beginning and maintaining a better breathing rehab program (whether inside the medical community or by enterprising, qualified trainers/therapists outside the medical community) the likelihood of exercise adherence will increase and the conditioning gains achieved during such programs will be sustained.

New Medicare Rules Now In Effect for Pulmonary Rehab – A Mixed Blessing

In a blend of good news and bad news, Medicare enacted new rules for the reimbursement of pulmonary rehabilitation services effective on January 1, 2010.


For the respiratory care professionals who have lobbied long and hard for changes in how Medicare (and ultimately other health insurers) reimburses practitioners for providing pulmonary rehab services, there is a measure of satisfaction that some progress was made in the new reimbursement rules. On the other hand, the degree to which these dedicated pulmonary physicians and therapists have had to fight in order to get a handful of modest changes enacted has surely been frustrating.


To take a step back, it is important to understand that pulmonary rehabilitation as a practice has been fighting for reimbursement recognition for a very long time. This is mostly due to the fact that there are few "hard data" measurements to demonstrate successful patient outcomes in pulmonary rehabilitation. In this profession, practitioners typically use results of six minute walk tests and patient quality of life surveys to measure patient improvement from admission into a program to graduation (both in research studies and clinical evaluations). Since most of the patients they see have developed irreversible lung damage anyway, the best respiratory professionals can do is help people feel better and better manage their conditions (and if patients stick with it after formal rehab, slow the progression of lung disease and reduce the incidence of future shortness of breath attacks). There is unfortunately no current diagnostic/statistical measure that one could look at and say pulmonary rehab definitively improved Patient X's lung function.


But insurers, including Medicare, want to make certain that they reimburse practitioners only for services that produce a verifiable improvement in patients' health (understandably so). While the body of scientific evidence of pulmonary rehab's effectiveness using the above two measures is substantial and impressive, they are not the same sort of statistics that insurers prefer to validate patient outcomes. Despite this bias, over the last two decades, respiratory care professionals have opened Medicare's minds enough to these measures as descriptive of patient outcome to achieve insurance reimbursement.

So what's changed in the new Medicare rules and how will these changes help people interested in pursuing pulmonary rehab?

Though there were a host of changes in the new ruling the two most important changes enacted in terms of broadening access to pulmonary rehab were as follows:

• A single, nationwide reimbursement category for pulmonary rehabilitation services was established that covers most of the core elements of pulmonary rehab services (known in Medicare speak as a National Coverage Determination). Prior to this change, there was no central, nationwide reimbursement standard/amount for providing pulmonary rehab services. Practitioners had to utilize an array of individual codes for specific services performed during pulmonary rehab sessions and these codes varied from region to region in the U.S. (known as a Local Coverage Determinations). It was cumbersome to track/report on all of those codes and not all pulmonary rehab services were covered. As a side effect of the previous reimbursement situation, many hospitals today do not offer pulmonary rehab services given the combination of coding hassle factor and how low reimbursement levels are compared to the cost of providing these services. 

For your information, the amount that practitioners can be reimbursed for a 1-hour rehab session under the new rule is $50. When you consider the cost of outfitting and staffing a pulmonary rehab facility (doctors, therapists, medical equipment, exercise equipment, physical space), this is a very modest sum – but it's a lot better than Medicare's original proposed amount of $19/hour! 

Prior to the reimbursement rule change, practitioners could be reimbursed in 15 minute increments of $18 for certain specific/discreet services. So if a practitioner conducted an hour long session that was comprised of 4 reimbursable services, they received $72. As a result, the new all-encompassing reimbursement rate is less than stringing together four individual pulmonary rehab services in a one hour session but at least the new reimbursement category doesn't involve the same amount of hassle in coding/tracking the incremental services and it covers a broader array of services (though a slew of new cumbersome requirements were created to assess patient progress in order to achieve reimbursement under the new rule). By the way, practitioners can still utilize the Local Coverage Determinations if they want to continue to seek reimbursement as they have in the past (and our guess is that many will).

• The number of allowable reimbursed sessions/patient increased from 36 1-hour sessions to 72 1-hour sessions. This allows practitioners to offer a longer course of pulmonary rehab, and/or to provide a maintenance program after patients complete their initial core program. This is a pretty big change. It essentially allows practitioners the ability to double the amount of pulmonary rehab offered to patients. In the past, when a patient had exhausted his/her insurance/Medicare coverage, they graduated and were expected to continue pulmonary rehab on their own or at their own expense. Knowing that it takes more than a few weeks to solidify a lasting commitment to new health habits, this is a very welcome improvement.
   

Sounds like a pretty good deal right? Well, yes and no. There is at least one really big remaining shortcoming of the way pulmonary rehab services are reimbursed:


Pulmonary rehab services covered by this new Medicare National Coverage Determination are extended only to COPD patients and limits reimbursement to those patients identified as Moderate to Severe (known in the medical profession as Stage II and Stage III COPD). In other words, the new reimbursement rules do NOT cover pulmonary rehab services for nearly any other lung condition nor for patients who have either Mild or Very Severe COPD.


Folks, the reality is pulmonary rehab is an effective treatment for ANYONE who experiences chronic shortness of breath - whether or not you have been diagnosed with COPD or some other form of lung disease/condition (and in our opinion, even if you are a smoker who has yet to be diagnosed with any lung disease but are concerned about chronic or persistent shortness of breath).

The cruel irony of the way that pulmonary rehab services are offered and reimbursed is that you have to be "Goldilocks" to get access to a program that is reimbursed by insurers. You can't be too sick (ala Very Severe COPD) and you can't be too healthy (ala mild COPD) and you can't have nearly any other lung disease other than COPD.


The sad part of this situation is that it is clear that the less lung damage you have when you begin a pulmonary rehab style program, the better off you will be if you stick with such a program. If you already have lung disease, the earlier in the development of your condition you start and maintain such a program, the better chance you have of slowing the progression of lung disease.


From a health care cost standpoint, beginning and maintaining a pulmonary rehab style program earlier in the development of lung disease would lower the number and duration of future hospitalizations associated with COPD and quite likely reduce the need for medications and oxygen therapy (neither of which do anything but relieve short term symptoms) – all very costly medical services that far exceed the cost of providing pulmonary rehab to a wider audience of people who suffer from chronic shortness of breath!

And so while the new Medicare rules are a demonstrative step in the right direction, there is still a significant amount of more work to do to get pulmonary rehab into the lives of more people for whom it can make a substantial difference in how they feel and live.

Can nutritional supplements help people with breathing difficulties?

The broad answer to this question is…maybe. While there have been a number of studies conducted globally about the effectiveness of certain nutrients in improving various aspects of health for COPD patients and other pulmonary conditions, it would be a significant stretch to say there is consensus in the medical community about their usefulness.

Most often, respiratory care professionals point to the lack of multiple, large studies confirming effectiveness of certain supplements as their primary objection to advocating a particular supplement. This is a reasonable objection that is the primary weakness of the vast majority of the research done in the nutritional supplement field.

Since nutritional supplements are by and large commodity products, individual supplement manufacturers/marketers are generally not willing to fund large studies on their own when positive results published from their studies can be immediately used by their competitors to market competitive products. There are exceptions of course. Some ingredients can be patented, and some uses of combined ingredients can be patented, but for the most part there is no intellectual property protection for commonly found ingredients in food. Hence, investments in large scale supplement studies generally does not happen – at least on the scale physicians are used to seeing invested in pharmaceutical studies. As a result, the supplement studies do not carry the same credibility as pharma studies within the pulmonology profession. That all said…

In our opinion, it is worth your investment of time to learn about some of these supplement studies because some of the results are impressive even though the studies are small. We give you one example here and we will write of others as we find ones worthy of your attention:

In 2006, a group of Brazilian researchers investigated whether adding the nutritional supplement L-Carnitine would provide a noticeable benefit to COPD patients undergoing a pulmonary rehabilitation exercise program.

L-Carnitine is an amino acid used in the human body to facilitate energy production (it acts as a carrier of fatty acids to the mitochondria in muscle cells where energy to move muscles is produced). It has been shown in other studies to produce a noticeable effect in exercise tolerance in populations with nutritional or muscular deficiency but had never been previously studied in COPD patients to the best knowledge of the researchers. The free full text of the study can be found by clicking here.

In this study, the researchers split 16 moderate to severe COPD patients into two groups – a carnitine group that received 2 grams of L-Carnitine daily for 6 weeks, and a placebo group that received a placebo pill for the same period of time. During this six week period, both groups exercised on a treadmill for 30 minutes a day, three days a week at identical workload levels. Both groups' physical conditioning and vital health statistics were evaluated before and after the six week period.

While both the placebo group and the carnitine group experienced notable improvements in their physical conditioning and vital health statistics due primarily to the benefits received from the exercise program, the carnitine group's improvement notably outstripped the placebo group.

The researchers concluded the carnitine group's higher level of improvements in conditioning and vital health statistic measures were driven by the addition of L-Carnitine, "The main results of the present study show the beneficial effects of L-carnitine supplementation in enhancing physiological responses at identical levels of exercise, reducing lactate concentration, improving exercise tolerance and inspiratory muscle strength in COPD".

The study measured relative performance between the two groups in distance walked at peak speed, distanced walked in six minutes, heart rate at peak speed & same speed, blood pressure, blood lactate production, and other physiological measures. In all cases, the carnitine group outperformed the placebo group.

The researchers acknowledged that one of the weaknesses of their study is its small sample size (16 subjects). Does this invalidate the results? No, but it doesn't get American Thoracic Society to offer an endorsement of L-Carnitine (rightly so, until others can replicate the findings, hopefully in larger studies).

Despite this, should you try L-Carnitine if you are a COPD patient and are trying to start or maintain an exercise program? Read the full study at the link provided above and judge for yourself. Presuming you've checked with your doctor to ensure that there are no counter-indications with medications you currently take, we think it is worth considering.

If instead you'd like to find food sources containing high amounts of L-Carnitine, the highest sources are found in the meat of lamb and sheep (mutton) but you'd have to consume a lot of lamb/mutton each day to yield 2 grams of L-Carnitine…2 lbs. of mutton or 5.6 lbs. of lamb each day!

New Study Reinforces the Benefit of Sticking With Pulmonary Rehab Practices after Graduating From an Outpatient Program

A French study published in December 2009 revealed that COPD patients who continued exercising and receiving education/support through an informal maintenance program after a formal pulmonary rehab program demonstrated significant improvements in exercise tolerance, perceived shortness of breath and self-reported quality of life.

In my mind this study reinforces the need for more proactive efforts by the medical community to educate COPD patients (and pre-COPD patients for that matter) about the power of pulmonary rehab and to provide greater ongoing access for these patients to continue their own "maintenance" program at home, a fitness center or other appropriate venue after graduating from an outpatient program. The more pulmonary rehabilitation access, education and guidance COPD patients receive and the longer they receive this combination, the better they feel and perform. Plain and simple.

It is one of the main reasons I created the Breathe Better for Life guide/CD (click here to learn more) – to put the knowledge of the principles and practices of pulmonary rehabilitation in the hands of people who struggle to breathe so they have a fighting chance of maintaining or improving how they feel throughout their lifetime. It's also why I continue to investigate and develop new pulmonary rehab tools, technology and publishing products - to help the medical community meet this clearly growing need.

In this particular study, the research team led by Gregory Moullec and G. Minot at the University of Montpellier in Montpellier, France, set out to determine whether COPD patients graduating from a typical pulmonary rehab program would maintain or increase conditioning benefits and quality of life survey scores by continuing the practices and principles learned in the pulmonary rehab program (Moullec G, Minot G. An integrated programme after pulmonary rehabilitation in patients with chronic obstructive pulmonary disease: effect on emotional and functional dimensions of quality of life. Clin Rehabil Online. December 21, 2009). Full text of the study is available for purchase by clicking here.

In doing so, the researchers first screened moderate to severe COPD patients and yielded 27 subjects who completed the study. All 27 patients went through an intensive 4 week outpatient pulmonary rehab program (20 sessions over the 4 week period). After graduation, they split their study group of 27 COPD patients into two different panels. In one group, 16 graduating COPD patients were provided what the researchers deemed "usual after care". In short, this group received a letter upon graduation outlining a recommended home-based exercise program and sent on their way to self-manage (or not).

The other group of 11 COPD patients joined a regional health network in their local area linked with a self-help association comprised of former pulmonary rehab graduates. With these resources at hand, the second group, denoted by the researchers as the "integrated care group" continued to go to exercise sessions at a local gym supervised by a trainer of sorts with experience in working with people who suffer from chronic disease (referred to in the study as a teacher of adapted physical activities). This second group also received periodic health education visits by representatives of the regional health network and periodic psychologist visits at a local community center.

The researchers evaluated the two groups' physical conditioning and quality of life ratings at 6 months and 12 months after graduation. The results of the two groups are very telling. For example, in one of the prime measures of exercise capacity, the six minute walk test (6MWT), patients from both groups saw their mean six minute walk distances (6MWD) rise at the end of the formal 4 week pulmonary rehab program by 45-52 meters (11-13% improvement) compared to their performance on a 6MWT at the beginning of the program.

However, 6 months and 12 months after graduating the formal rehab program, the "usual after care" group experienced an 8% DROP in 6MWD. In contrast, the "integrated care group" demonstrated an 8% RISE in 6MWD. What's driving the difference? In the researchers view, it is the ongoing commitment of support resources for the "integrated care group". And these same statistically significant differences were demonstrated in nearly all of the measured elements of the study – from perceived shortness of breath to peak exercise load to self-reported quality of life scores, and so on.

The practical reality is that providing these ongoing support resources in today's U.S. health care environment is difficult if not impossible from the standpoints of insurance reimbursement, practitioner capacity and facility capacity.

But what's the alternative? Send people off with a letter to go at it alone? Wait until the patient has a breathing exacerbation event that lands them back in the ER? Forget about them and move on to the next patient?

I don't think so, and I know many pulmonary rehab practitioners don't think so either. But until someone finds a way to dramatically broaden access and/or lower cost of providing pulmonary rehab type services (which, by the way, I'm working on one potential solution currently), graduating COPD patients have nowhere to turn and scant information to use to pursue a maintenance program on their own. My Breathe Better for Life guide/CD is a step in the right direction but it is only a step. Much more is needed if respiratory care professionals truly want to make a noticeable dent in helping people breathe better for the long term.