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 COVID vaccine hesitancy, antibiotic prophylaxis for sexually transmitted infections (STIs), colonoscopy in older people, and what is the best diet to reduce mortality?
Program notes:
1:15 Why don't people get COVID vaccines?
2:15 Vaccine acceptance in future scenarios
3:15 COVID vaccine like the flu vaccine
4:15 Triple vaxxers
4:50 Diet and mortality
5:53 Mediterranean diet decreased most
6:50 Olive oil instead of saturated fat
7:04 Post-exposure doxycycline for STIs
8:02 Reduced from 32% to 11%
9:03 Interrupt the transmission in general
9:25 Colonoscopy in those older than 75
10:25 Percentage with less than 10-year life expectancy
11:25 Fecal tests instead
12:01 End
Transcript:
Elizabeth: What makes different groups of people decide not to get a COVID vaccine?
Rick: Do all dietary programs reduce the risk of death?
Elizabeth: Can we give a common antibiotic to prevent sexually transmitted infections among gay men?
Rick: What happens when we do colonoscopy in individuals older than 75 years?
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, before we start I want to give a shout-out to our long-time partner, Tom Jackson, who is a Canadian who has been following us ever since the beginning.
Elizabeth: It's truly amazing. Tom, of course, is the veterinarian up there in Canada. I think Tom bears witness to the idea I have had for a long time that veterinarians are even smarter than doctors.
Rick: When we talk about One Health, i.e. health that transcends both human and animals, Tom always gives us insightful perspectives on our weekly podcast. Elizabeth, where do you want to go?
Elizabeth: Well, we're going to do what we always do when we have COVID studies. We're going to turn first to Nature Medicine. This is a study that's entitled Determinants of COVID-19 Vaccine Fatigue. It's clearly something that is poised to be important for all of us if we have new COVID variants that continue to develop; we will have those of course. Will any of them become more transmissible, once again more lethal? Those are open questions and we don't know the answer. We do know, however, that new vaccines are going to be important and boosters are likely to be important in the eventualities that I've described.
This study took a look at 6,300+ participants who lived in Austria and Italy. They were asking these folks, hey, who are you? Can we explain your reluctance or not that you're reluctant to get a COVID booster, or even vaccination to begin with?
They looked at vaccine acceptance in future scenarios. Among unvaccinated people, campaign messages to have a vaccination that ask to engender their community spirit had a positive effect. They also looked at positive incentives such as cash rewards or vouchers, and those were really important among those vaccinated once or twice previously. Then among those of us that are triple vaccinated, vaccination readiness increased when adapted vaccines to current variants were available.
They finally say for a long-term success what we really need to do is look at all of these different factors among all of these different populations and we need to employ measures that foster institutional trust. These are some pretty tall orders.
Rick: You have to take the first vaccine and then you also have to get the boosters. For the people that don't take the first vaccine, they call that a vaccine hesitancy. Those that don't complete the boosters, they call that vaccine fatigue. Why that's important is because I think the COVID vaccine is going to be very much like the flu vaccine, where you've got one dose, but we're probably going to have to have annual doses.
What are the determinants of vaccine hesitancy and vaccine fatigue? As you mentioned, they are different. Understanding what these are is going to be contextually important to make sure that people get the vaccine and complete the booster.
Elizabeth: I have found some of the specific identifications among these different populations to be very interesting. For example, among the never vaccinated, any attempt to kind of strong-arm them with laws to compel them to get vaccination turned out to be really not a good idea at all. They also looked at this notion of cost. They found that even minor costs could strongly reduce vaccine uptake.
Rick: Specifically boosters. Cost didn't matter as much with the initial dose -- as you said, trust did -- but cost did matter when people were looking at subsequent boosters.
Elizabeth: Right. Then among, I'm going to call it, our population, which are the triple-vaxxers and above, one factor that they identified as important was celebrity endorsement. I thought to myself, "My goodness, I couldn't care less about a celebrity endorsing getting another vaccine." What about you?
Rick: I'm not so sure it's a celebrity as much as it is somebody just reminding us that we need to continue with the boosters. This is a really interesting study. How do we address both vaccine hesitancy and vaccine fatigue?
Elizabeth: Right, and it's going to require a nimble and multifactorial approach.
Rick: Right. Speaking about multifactorial approach, let's go to The BMJ and let's talk about diets.
Now, there are so many different diets out there. Obviously, the diets are intended to help people lose weight. The diets I'm most interested in are those that not only help people reduce weight, but also reduce mortality and reduce cardiovascular effects.
What this study did was it looked at randomized trial and did a network analysis. Network analysis allows you to compare different diets even though they weren't studied in the same trial. They looked at seven different diets: a Mediterranean diet, a low-fat diet, a very low-fat diet, a modified diet, a combined low-fat and low-sodium diet, an Ornish diet, and a Pritikin diet -- 35,000 participants across these seven different studies.
What they discovered was the only two diets that were convincingly shown to decrease mortality were the Mediterranean diet and the low-fat diet. The Mediterranean diet decreased mortality by about 25% to 30%. It decreased cardiovascular mortality by about 45% and stroke by 35%. The low-fat diet a little bit less, but they didn't find any convincing evidence there was really any significant difference between the two.
Elizabeth: I'm very interested in the low-fat diet because, as we're well aware, when we've looked at these things in the past we know that frequently if people try to achieve low fat they end up subbing in other things. I'm wondering about, of course, simple carbs and how that might impact on the development of diabetes. There is probably not anything that granular in here, is there?
Rick: No, you're absolutely right. There is not. When they talked about low-fat diet, they just meant that just only about 20% to 30% of the calories come from fat.
Elizabeth: I guess the Mediterranean diet -- I have been seeing a lot about it in a lot of other studies really touting it as the best. Maybe it's just worthwhile just reminding everyone what that is comprised of.
Rick: It's heavy with fresh fruits, fresh vegetables, nuts, the use of olive oil instead of saturated fats, and alcohol in moderation. It's the only one of the diets to convincingly decrease stroke and it also decreased heart attacks as well.
Elizabeth: Let's turn to the New England Journal of Medicine. This is a look at post-exposure doxycycline to prevent bacterial sexually transmitted infections. This is among men who have sex with men. I'm interested in this because, of course, we're seeing pretty concerning data regarding things like neonatal syphilis increasing and also skyrocketing rates of gonorrhea that is resistant to a lot of our antibiotics. This notion that "Can we give somebody post-exposure doxycycline and prevent these STIs?" is pretty compelling.
There were 501 participants in one cohort and 175 in the other. What they did was randomly assign these folks in a 2:1 ratio to take 200 mg of doxycycline within 72 hours after condomless sex and then they looked at, "How many STIs did you develop?"
The testing was performed quarterly. Use of doxycycline was able to reduce the number of STIs in one population from 32% to about 11% and in the other group from 30.5% to about 12%. Interestingly, even though gonorrhea is not necessarily susceptible to this, they did show that gonorrhea was actually reduced and chlamydia and syphilis, lowered by two-thirds with this particular regimen.
Rick: These are again males having sex with males, some of whom had HIV and were being treated, and in both groups the use of post-exposure doxycycline decreased sexually transmitted infections.Here is one of the major concerns I have about this. When you increase the use of antibiotics, especially in the post-exposure period, eventually you may develop resistant-sexually transmitted infections.
Elizabeth: I wonder about that too, Rick. I also wonder about -- and we know that this is true -- that there is substantial spillover from these populations like men who have sex with men into other populations who are having sex. So if we could just interrupt that transmission in general, then maybe we would just overall have fewer STIs that we have to worry about and this notion of resistance then may not be so robust.
Rick: I'm not suggesting that we shouldn't provide post-exposure doxycycline, but what I am saying is that we do need to follow it.
Elizabeth: Let's turn to your final one. That's in JAMA Internal Medicine, colonoscopy and those who may not really need it. That's my editorial.
Rick: The USPSTF, the United States Preventive Services Task Force, recommends routine colorectal cancer screening in patients between the ages of 45 to 75. Between the ages of 76 and 85, the USPSTF and the American Cancer Society recommend that screening be individualized. The reason for that is the benefits for colorectal cancer screening take 10 to 15 years to accrue because what we're looking for is we're looking for polyps that don't develop into cancer for 10 to 15 years later.
What these investigators did was they determined the number of screening colonoscopies that were done in patients over the age of 75, especially those that had a life expectancy of less than 10 years. They also looked to see whether there were any adverse effects from doing colonoscopy in older individuals.
Over a period of about 13 years, they identified over 7,000 patients over the age of 75 who had had colonoscopy. The percentage of individuals that had a life expectancy less than 10 years was about 30%. Unfortunately, adverse events requiring hospitalization, there was about 13.5 to 14 per thousand individuals. That number went higher the older individuals got. How good was it at finding advanced cancer? Two out of 1,000 patients.
Elizabeth: I don't know how many decades ago, Rick -- and probably we don't even want to talk about how many decades ago -- we started recommending screening colonoscopy for those aged 50 and older, and people sort of got that into the routine that that's what they needed to do. Trying to get people now to step away from that, even if you're 75, and say, "Oh, I don't need to have this any more," is really a tough call. I have even seen it among practitioners who are still recommending that.
We've also got fecal screening of various types that we can perform if we have a suspicion of colorectal cancer. Why not employ those instead and give this colonoscopy a miss, especially in older people?
Rick: Even if you do a different test that may be safer and you find a cancer in an individual whose life expectancy is less than 10 years, you're probably not going to treat it. In fact, that's exactly what happened in this study. There were nine individuals they discovered cancer and eight of those nine said, "Well, I don't want to undergo therapy. I mean, it's not going to really prolong my life and it's going to likely make me miserable." It's not just the test itself, but what are you going to do with the results once you find them?
Elizabeth: Always a good point. On that note, 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.