U.S. Exercise Levels; Lifestyle and Memory Decline; Cooling Kidney Donors

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 physical activity and diabetes risk, overall levels of exercise in the U.S., cooling down kidney donors, a vaccine for meningococcal disease in kids, and a healthy lifestyle and mental decline.

Program notes:

0:45 Healthy lifestyle and memory decline

1:45 Regardless you still experience memory decline

2:45 Very quantitative tests

3:00 People with obesity, exercise and diabetes

4:00 Two years and even up to ten years

4:35 MMWR look at physical activity in adults

5:35 Combined aerobic and strength

6:30 Cooling organ donors

7:30 Machine perfusion best

8:30 Organs go to multiple locations

8:45 Vaccine for meningococcal group B

9:45 Nationwide case matched study

10:30 Had vaccine against group C

11:30 End

Transcript:

Elizabeth: The efficacy of a vaccine against meningitis in kids.

Rick: Can a healthy lifestyle affect memory decline in older adults?

Elizabeth: What’s the impact of moderate and vigorous exercise on diabetes in adults with obesity, and how often are we really exercising anyway here in the U.S.?

Rick: Does being cool make kidney transplant more successful?

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 the dean of the Paul L. Foster School of Medicine.

Elizabeth: In the absence of any COVID material this week, which one would you like to start with, Rick?

Rick: We’ve got a lot to talk about with regard to healthy lifestyle and exercise, so let’s start with that. I teed it up as, “Can a healthy lifestyle actually affect memory decline in older adults?” Because we know that that happens: as we get older, our memory declines.

In this large study of individuals who were 60 years or older and had normal cognition at baseline, they assessed six healthy lifestyle factors: diet, activity, active social contacts, active cognitive activity, whether they smoked or not, and whether they drank alcohol or not. They also assessed whether they were at risk for dementia by looking at APOE.

What they discovered is in over 29,000 individuals they followed for over a decade, if they were involved in four or more of those healthy lifestyle activities that I mentioned, there was a significant effect in terms of their memory decline. That was true, regardless of whether people were at risk for dementia, or whether they were not at risk of dementia.

Elizabeth: What I thought was really disconcerting about this study was looking at the tables, and the tables clearly show that regardless of whether you employ all these healthy lifestyle factors or not, you’re still going to experience memory decline as you age.

Rick: Elizabeth, that’s a great summary because memory continuously declines with increasing age. But it’s nice to know that a combination of these really positive healthy behaviors can actually slow the rate of memory decline in adults, even if people are genetically susceptible.

Elizabeth: Right, those with that APOE4 gene. One of the things that I also thought was noteworthy in this study was the fact that of all of these factors, it looked like the exercise had the biggest bang for the buck.

Rick: But it’s not just a single factor, it’s actually the combination. They divided it by those that had 0 or 1 of those activities, those that had 2 or 3, and those had 4 to 6. Those individuals that had 4 to 6 of these healthy activities had the best effect with regard to slowing it down.

Elizabeth: By a very modest amount, I would also note.

Rick: It’s hard to put it into real life activities. Like will you remember two more names, or will you forget less? But on these very specified, very quantitative tests they are able to clearly demonstrate these healthy lifestyles helped to slow memory decline.

Elizabeth: Since we’re doing a lot of talking — that’s in the BMJ by the way — about exercise and its benefits, let’s turn to two studies that we’re going to treat together. One is a research letter in JAMA Internal Medicine and the other one is CDC data from Morbidity and Mortality Weekly Report (MMWR).

Let’s turn to the first one first — the research letter. Basically, this is a study taking a look at adults with obesity as a 10-year follow up of a randomized clinical trial. They wanted to see whether diet and regular exercise can be effective, or how effective can it be, for the prevention of type 2 diabetes in these folks who are clearly at very high risk to develop it. Lo and behold, in this analysis, they found it could reduce their risk of developing type 2 diabetes by about 50% and that’s really pretty powerful.

Rick: As you mentioned, this is a 1-year exercise program. They can do either vigorous or moderate exercise, or no exercise. Any type of exercise was moderate or vigorous decreased their risk of diabetes by 50% over a 10-year period. Those results were manifested 2 years and even extended out to 10 years.

If we had a medicine that I could prescribe to somebody and say, “If you took this, even if it was expensive, it would decrease your risk of diabetes by 50%,” I’d have people standing in line. Here, we have something that really doesn’t cost very much. Oh, maybe some new running shoes or a workout suit, or maybe some soap to shower after you’ve done the exercise. But overall, it’s not costly. Even 1 year of exercise for delaying diabetes or decreasing the incidence 2 and 10 years later.

Elizabeth: Exactly. That’s so amazing. It’s like the benefit of a vaccine, almost, against the development of that disease.

Let’s turn then to MMWR. This is a rather daunting, of course, assessment of just how often are adults meeting activity guidelines during their leisure time. They take a look at this by rural and urban classification and region in the United States in 2020.

What’s interesting to me about this is that during the pandemic, there was a lot of information coming out about how adults were out there doing way more exercise than they had done previously. These results would seem to belie that. More rural areas are way less likely to meet the guidelines than are urban areas. The Northeast, the Midwest, the South, and the West are very divergent, with the South having the worst record with regard to people really getting out there and doing these forms of exercise.

I’m not sure that I remembered that there were three recommendations and these regarding aerobic exercise, muscle strengthening, and combined activity. They note that the only place that really had about half of the people meeting those guidelines is the West. No matter where you look, if you look at rural/urban classifications and regions, no more than 28% of adults met these combined aerobic and muscle strengthening guidelines. I have to admit that if you ask me about my exercise regimens, I’m not sure I would actually meet these guidelines.

Rick: That’s the point. Only about a fourth of people end up meeting the guidelines. This is despite all the education and all the advertisement that goes with this.

Now, we’re talking about aerobic exercise. We’re talking about doing 150 minutes per week or more. That’s 30 minutes a day, 5 days a week of either moderate or vigorous activity. For muscle strengthening, we’re talking about doing it 2 or more days per week, and ideally you’d like to do both.

Elizabeth: On that daunting note, why don’t we turn to the New England Journal of Medicine taking a look at cooling kidneys?

Rick: It’s been clear that cooling individuals down that are organ donors has shown to reduce delayed graft function in kidney recipients after they have had a transplant. For the donors, we know that there are a couple of possibilities. One is to extract the kidney and just put it on ice, and take it to where it’s going to be implanted in the recipient. The second is to put it on a machine to perfuse it and the results of the machine perfusion is actually better. Unfortunately, only about a third of places performing transplant have that capability.

What they attempted to determine here is, “What about if you take the recipient and cool them down until we’re ready to harvest the kidneys? Let’s compare that to putting the kidney on a perfusion scheme and then finally compare it to both.” After you put the kidney in, does the person have to be on dialysis for a while until the kidney recovers, and is a kidney still working a year later? What they discovered is when they put the kidney on the machine perfusion to make sure it had adequate blood flow, that was the best result.

Elizabeth: I thought that some of the data that was cited in this study relative to the number of kidneys that go to waste was really pretty saddening.

Rick: Sometimes they are not a good match for the recipient and then in an occasional person it just doesn’t take. That happens at about 5% to as many as 10% of individuals over the course of the year.

Elizabeth: I thought I saw something in here though about how long it takes to transport them sometimes and that they are not really kept at the proper temperature and all that — that that results in organ loss.

Rick: That’s a part of the problem, Elizabeth. Now, if we had machine perfusion available everywhere, that would be less of an issue. But just in this particular study, the mean time for cold ischemia — and that is how often were these organs kept cold in this particular study — ranged from about 17 to 19 hours. That obviously affects the viability of the kidney.

Elizabeth: What this points out to me is the idea that somehow we really need to synthesize the availability of organs for transplant, their transport strategies and mechanisms, and also facilitate that transport so that these things arrive viable.

Rick: That’s a great point. These organs from our donors can go to multiple different locations around the United States.

Elizabeth: Finally, remaining in the New England Journal of Medicine, a look at a vaccine against meningococcal group B organisms in children in Spain. From the CDC, I learned that invasive meningococcal disease remains a public health problem and a leading cause of morbidity and mortality worldwide.

There are 13 serogroups of Neisseria meningitidis; only five of those are really responsible for most of the invasive meningococcal disease. While all age groups are at risk for this disease, infants and adolescents are particularly at risk. Death occurs in 6% to 10% of cases and sequelae in 4% to 11% of cases. I don’t know if I really appreciated previously what a really big problem this is.

So in this case, they had since September 2015 the availability of a 4-component protein-based meningococcal serogroup B vaccine that was available for private purchase in Spain. They conducted a nationwide matched case-control study to take a look at the effectiveness of this 4CMenB vaccine they abbreviated in preventing invasive meningococcal disease in children.

They were looking at this in those younger than 60 months of age. They took a look for about 4 years. Each case patient was matched with four controls. They had 306 cases and 1,224 controls. Efficacy of the vaccine was 76% in those who had received 2 doses. At least one dose it was 64% effective and interestingly 82% effective against the non-serogroup B disease in addition to the B disease.

Rick: We’ve had a vaccine against the serogroup C. In fact, in this particular study, less than 2% of the infections were due to serogroup C. Now most of them are due to serogroup B. The advent of a vaccine against serogroup B that’s effective is really important.

This is one of the few vaccines that we give very early on. It’s such a serious disease with the high mortality. Our recommendation is to start immunizing kids at 2 months of age and the second dose at least 60 days after that, but usually about 12 to 15 months after the initial dose. The two-dose vaccine regimen, as you mentioned, is incredibly effective. In fact, Elizabeth this Men4BC vaccine is a part of the updated recommendations for immunization of young children.

Elizabeth: Good news. On that note, we like good news. 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.