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Carbohydrates and Long-Term Weight Change; Value of Cardiac Transfers

— Also in TTHealthWatch: reducing infections in joint replacement

MedpageToday

TTHealthWatch is a weekly podcast from Texas Tech. In it, Elizabeth Tracey, director of electronic media for Johns Hopkins Medicine in Baltimore, and Rick Lange, MD, president of the Texas Tech University Health Sciences Center in El Paso, look at the top medical stories of the week.

This week's topics include reducing infections with joint replacement, long term weight and carbohydrate consumption, treatment of recurrent prostate cancer, and lack of benefit in transfer to a specialized cardiac care center.

Program notes:

0:42 ARREST trial

1:42 Either a cardiac center or standard ED

2:42 Substantially higher utilization of resources

3:42 Don't have a cardiac cause

4:42 Worse 57-71 years of age

5:22 Biochemical recurrent prostate cancer

6:23 Five-year metastasis free survival

7:24 New advances in prostate cancer

7:40 Carbohydrate consumption and long-term weight change

8:40 Refined grains, starchy vegetables and increased gain

9:46 Way to avoid infection with knee and hip replacement

10:45 Vancomycin in addition

11:45 Fairly low incidence

12:10 End

Transcript:

Elizabeth: What does the look at long-term consumption of different types of carbohydrate tell us about weight?

Rick: Improving outcomes in men with recurrent prostate cancer.

Elizabeth: In certain types of heart attacks, does it make sense to transfer people to a cardiac arrest center?

Rick: And does intensifying antibiotic therapy make hip and knee replacement safer?

Elizabeth: That's what we're talking about this week on TTHealthWatch, your weekly look at the medical headlines from Texas Tech University Health Sciences Center in El Paso. I'm Elizabeth Tracey, a Baltimore-based medical journalist.

Rick: And I'm Rick Lange, president of Texas Tech University Health Sciences Center in El Paso, where I'm also dean of the Paul L. Foster School of Medicine.

Elizabeth: Rick, I'd like to turn this week directly to The Lancet and the reason I want to turn to this study is because I was pretty surprised, actually, by the results. This is entitled "Expedited transfer to a cardiac arrest centre for non-ST-elevation out-of-hospital cardiac arrest," the so-called ARREST trial.

This was done in the UK. It was prospective, multicenter, and randomized, which is highly unusual when these are the kinds of outcomes we're attempting to examine. In point of fact, the authors talk about their scrutiny of the literature and say that almost everything that has attempted to inform the utility of cardiac arrest centers previously has been observational. Therefore, this is, they claim, the first study that is of this type.

They brought in patients with a return of spontaneous circulation following out-of-hospital cardiac arrest without ST elevation. These folks were randomly assigned 1:1 at the scene of their cardiac arrest by the London Ambulance Service Staff to either 1 of 7 cardiac arrest centers or standard-of-care delivery to the geographically closest emergency department at one of 32 hospitals in London. Their primary outcome was all-cause mortality at 30 days.

They found over this time period it took them 4 years to accumulate sufficient patients for this. 862 patients were enrolled, half and half randomized to these two different types of centers. Ultimately, they ended up with 411 participants in the cardiac arrest center group and 412 in the standard care.

Thirty-day mortality occurred in 63% of the patients in the cardiac arrest center group and 63% of patients in the standard care group, so there was no difference in outcomes. There were things that were different, however, and the things that were different in the cardiac arrest centers were substantially higher utilization of resources for things like intubation and dialysis. None of it resulted in a difference in outcome. I was floored by this.

Rick: Elizabeth, as you mentioned, it took 4 years to complete this study and part of the reason is, these are very difficult studies to complete in survivors of out-of-hospital arrest, but it also occurred during COVID infection.

Here is what I think we can glean from previous experiences. It's that if you have a heart attack or cardiac arrest, those individuals seem to do better if they get transferred to a center that specializes in heart procedures. However, out-of-hospital cardiac arrest in these individuals that were thought to have a heart reason, 40% of them it wasn't due to the heart. Of the other 60% in which there was a cardiac cause in at least half of them, it didn't have to do with occlusion of an artery that you could open up. It had to do with an arrhythmia or heart failure or cardiomyopathy. Many of the individuals with out-of-hospital arrests don't have a cardiac cause and they don't benefit from going to a regional center.

Elizabeth: No question. Now, they do say that this study highlights the quality of care that's delivered by the London Ambulance Service and the importance of the first three links in their chain of survival: early recognition, CPR, and defibrillation. Kudos to them, and this is clearly not something that we enjoy in all kinds of urban centers either nationally or internationally. They also say that there was a possible survival benefit from the cardiac arrest center in participants younger than 57 years of age. It's going to be challenging to follow that up, though, I think.

Rick: Exactly. You have your initial study and then you try to break it down into various subgroups. In no subgroup was there any benefit of going to a cardiac center, except for perhaps a hint in those under age 57. If there is going to be an ongoing trial to target that group, parenthetically you did worse for people over the age of 57, particularly between 57 and 71. Overall balance, no benefit.

Elizabeth: If you had to point to a take-home from this or something you'd be looking for, would it be some better way to evaluate in the field exactly why someone seems to be presenting with a cardiac arrest?

Rick: Elizabeth, if we could do that, that would be good. Furthermore, as you mentioned, the most important things are early recognition, early CPR, and early defibrillation. That's saved a third of individuals that had already suffered a cardiac arrest. Anything that delays those things puts the individual at increased risk of death.

Elizabeth: Well, I'm not sure this study will be repeated, but I'm sure it's going to have some ripple effects. Which of your two would you like to turn to?

Rick: Let's talk about recurrent prostate cancer, talking specifically about men who have a high risk of what we call biochemical recurrence of prostate cancer. It's an individual that has been treated -- they have high-risk cancer -- we can't see any evidence of recurrence by our typical imaging. But we measure the PSA and the PSA begins to go up, and it's considered high-risk if the PSA doubles in less than 9 months.

We'd like to be able to try to treat those individuals even before we can see it, just based upon the blood test. Typically, those men are given what's called androgen deprivation therapy. There are new hormonal therapies, one called enzalutamide. What this study did is it took a group of men that have high-risk biochemical recurrence and it randomized them to typical androgen, randomized them to enzalutamide, and then the combination of both of those together, and followed them over a course of 60 months. There were over a thousand patients in the study, about a third of them in each of the arms.

What they discovered is that at 5 years when they looked at the metastasis-free survival, it was about 71% with androgen therapy, 80% in those that received enzalutamide, and 87% when the combination was given. That combination therapy didn't have any increased adverse events. This is a study that I think is very encouraging.

Elizabeth: Well, clearly that's an outcome that we're really interested in. One of the things I would ask is, how does the side effect profile with enzalutamide compare alone with androgen deprivation therapy?

Rick: As the authors put, there were no new safety signals observed without adding additional side effects.

Elizabeth: Side effects are pretty troublesome for a lot of men.

Rick: They are. Those side effects occur with androgen deprivation therapy alone, but the addition of the enzalutamide doesn't make that any worse.

Elizabeth: I think it would be really nice if we could figure up something that doesn't have the constellation of side effects that hormone deprivation has in men.

Rick: I'm pleased that it seems like every year we're able to report new advances in prostate cancer. This is a cancer that affects almost 300,000 new cases this year and almost 35,000 deaths from prostate cancer in the United States alone.

Elizabeth: Let's turn to the BMJ and this is a look at one of our favorite topics, I should say probably one of my favorite topics, which is diet. This one is the association between changes in carbohydrate intake and long-term weight changes.

It's a prospective cohort study. They use the data from the Nurses' Health Study, both I and II, and the Health Professionals Follow-up Study; 136,000+ men and women aged 65 years or younger and free of the whole constellation of things that people frequently develop as they age at the time of the study inception. They followed them up every 4 years during this time period and they looked at, "Well, what were you guys eating?" They were looking at not only what they were eating, but they were also looking at their weight gain.

Increased carbohydrate intake from whole grains, fruits, and non-starchy vegetables resulted in less weight gain over this time period, while consumption of all those refined grains, starchy vegetables, and sugar-sweetened beverages associated positively with weight gain and their weight gain was actually fairly substantial. They also noted that the magnitude of these associations was stronger among those folks who started out with overweight or obesity and these associations were stronger among women.

Rick: A couple things I found interesting. Over the course of follow-up, individuals gain an average of about 3 to 5 pounds per year. It kind of sneaks up on you. I think most people think carbohydrates are carbohydrates. What this study says is no. There are some carbohydrates you can eat where you actually don't gain weight or you gain less weight. It's not only the carbohydrate quantity, but it's also the quality and the source. We can manage our long-term weight gain just by changing the types of carbohydrates we eat.

Elizabeth: Of course, this harkens to our current dietary Darth Vader, ultra-processed foods.

Rick: Yes. We're not telling people you need to limit carbohydrates, but let's be wise about the ones that we eat.

Elizabeth: Returning to the New England Journal of Medicine, where our last study was from, now we're going to take a look at is there a way to avoid infection when you get your knees and your hips replaced?

Rick: These are 2 really high-volume operations performed in the United States. By the year 2030, it's estimated we'll do 2.7 million hip and knee replacements in the United States and the most significant morbidity associated with it is actually infections. The infection can be superficial in the skin that needs to be treated. If it's a deep infection, they can affect the device itself and the joints. It costs about $28,000 per infection in the United States.

Now, routinely individuals receive an antibiotic about 1 hour before the procedure starts, cephalosporin antibiotic. Unfortunately, some of the skin bacteria, the staph that we see, oftentimes is resistant to this antibiotic. What these authors said is, "Gosh, can we decrease the risk of infection if in addition to that we use vancomycin because staph bacteria are sensitive to vancomycin?" They looked at over 4200 patients and they randomized them to receive either the normal antibiotic or to receive cephalosporin and vancomycin.

What they discovered was fortunately the risk was fairly low. It was about 4% overall. Of those that did have an infection, 90% were superficial. Unfortunately, the addition of vancomycin did not lower that risk at all. On the good side, it avoids providing an antibiotic that's not helpful. It could potentially increase antibiotic resistance in the future and additional cost. The other thing I should say is these were individuals that weren't known to have resistant Staph aureus.

Elizabeth: I thought it was noteworthy that 4.5% of the folks in the vancomycin group and 3.5% in the placebo group developed these infections, so it's actually slightly more in the vancomycin group.

Rick: It was slightly more, but not statistically significant.

Elizabeth: I suppose it's good to know that we don't need to use more. It would be advantageous to not have any surgical site infections. I'm not sure how we're going to address that one.

Rick: It's fairly low-incidence. The vast majority of them were superficial and easily treated, which prevents it from becoming a deep infection.

Elizabeth: On that note then, that's a look at this week's medical headlines from Texas Tech. I'm Elizabeth Tracey.

Rick: And I'm Rick Lange. Y'all listen up and make healthy choices.