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 cardiovascular impact of low and moderate dose radiation, coffee consumption and heart function, testing in long-term care facilities and COVID-19, and delirium after surgery in older adults and subsequent dementia.
Program notes:
0:42 Testing in long-term care facilities for COVID
1:42 Pre-vaccine phase decreased rate by 30%
2:30 Coffee consumption in ambulatory adults and heart beats
3:30 Mean age 39 yrs
4:30 No change in serum glucose
5:30 Previous caffeine consumption
6:31 Ionizing radiation and CVD
7:30 Use lowest dose possible
8:19 Delirium, dementia and surgery in older adults
9:19 Up to 6 years of follow up
10:20 Is delirium a marker?
11:20 A little bit older at baseline
12:18 End
Transcript:
Elizabeth: What's the effect of coffee consumption on health among ambulatory adults?
Rick: Is low-dose radiation a risk factor for heart disease?
Elizabeth: What's the cognitive trajectory in older adults who have had surgery with regard to delirium?
Rick: If you do COVID surveillance testing in a nursing home, does it actually change outcomes?
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 Tracy a Baltimore-based medical journalist.
Rick: And I'm Rick Lange, president of Texas Tech University of Health Sciences Center in El Paso, where I'm also dean of the Paul L. Foster School of Medicine.
Elizabeth: Let's start with the COVID material in the New England Journal of Medicine. We haven't talked about COVID for a bit.
Rick: No, we haven't. This is a really well done study. It looked at whether surveillance testing for COVID-19 among staff members in a nursing home facility would actually improve outcome among the residents there in the nursing home.
One of the strategies to try to minimize infection in that group was to do routine surveillance testing among the staff, because most of the residents didn't get it from each other. They mostly got it from the staff.
On a regular basis, 2 or 3 times a week, regardless of whether there were any symptoms or not, you just test the staff members. You could do it with either point-of-care testing or some of the tests where you have to send off the swab and get an analysis. They looked at over 13,000 skilled nursing facilities and the staff members there during the three pandemic periods -- that is, before the vaccine was approved, before the Omicron variant, and then during the Omicron wave.
They looked at those nursing facilities in which routine surveillance testing was done, and those that weren't. What they found was that during the pre-vaccine phase of the pandemic, if they did surveillance testing, they could decrease the rate of infection by 30% among residents and decrease the rate of COVID-related deaths by 26%. The more often you did the surveillance testing, the better results, and the shorter the turnaround time as well.
Elizabeth: Was there any difference in the point-of-care versus sending off the specimen for testing?
Rick: Elizabeth, that's a great question. There really wasn't. But what they did know was if you can get the results back in less than 2 days, that mattered.
Elizabeth: Clearly, we know from a lot of data that we need to improve those tests a little bit also.
Rick: Yeah. I mean, there are some tests that are better than others, but what this shows is that routine testing is better than not routine testing.
Elizabeth: I thought that we would stay in the New England Journal of Medicine and talk about these acute effects of coffee consumption on health among ambulatory adults. This study starts with this notion -- we know this already -- that coffee is one of the most commonly consumed beverages in the world.
They were looking at this idea of caffeinated coffee on cardiac ectopy and arrhythmias, daily step counts, sleep minutes, and serum glucose levels. How did they get to this? Well, there have been previous studies and also speculation that caffeinated coffee could increase these arrhythmias and also aberrant beats of the heart, and that if you're on caffeine, maybe you move around a little bit more, maybe it disrupts your sleep, and gosh, what does it do with serum glucose? Because there appears to be a relationship with the development of diabetes.
What they did was recruited 100 participants. Their mean age was 39 years. Half of them were women and half non-Hispanic white. They had coffee consumption in these folks. They also fitted them with all sorts of devices so that they could record all of this data. They got randomized to 2 days of caffeine consumption and followed by 2 days of not caffeine consumption, and then 2 days of caffeine consumption and so on. Their primary outcome: daily premature atrial contractions. Other outcomes, as I said, step counts and sleep.
They also looked at ventricular contractions in here. What they found was that the caffeinated coffee was associated with 58 daily premature atrial contractions compared with 53 on the days when caffeine was avoided. With regard to premature ventricular contractions, there were 154 in a group when they did the caffeine and 102 in those who did not. Step count did increase to 10,646 when you drank the coffee versus 9,665 the days you didn't. You slept shorter and there was no change in serum glucose.
Rick: A couple of things. One is it's in the small group of individuals, it's 100. The question they asked I think is relatively important, because we're trying to avoid atrial fibrillation. It increases the risk of stroke, people have to take blood thinners, and so we're trying to minimize the risk factors. Does coffee contribute to that by increasing the risk of increased atrial extra beats? This study suggests that it doesn't. But, again, it's a young population and it doesn't really tell us how much coffee they really drink. It is kind of a ho-hum. I was kind of surprised -- I wasn't sure it was New England Journal of Medicine-worthy.
Elizabeth: What I want to know is why in the whole discussion they didn't talk anything about premature ventricular contractions? We did see that there was a difference in those among the caffeine consumption days and there was absolutely no discussion about that. What we know from older populations is that those are associated with a heightened risk of heart failure.
The other thing that I would like to know is, let's talk about the previous consumption of caffeine among this population they selected. Because if you picked me I have been consuming caffeine on a daily basis for decades. If you randomized me to a place where I was doing two on and two off, that wouldn't account for my caffeine consumption previous to ever entering this study.
Rick: Your points are very well taken. I'm surprised, too, that they didn't talk about the increased incidents of premature ventricular contractions. However, when you look at the totality of data, it looks like moderate coffee consumption is associated with a decreased cardiovascular risk. I agree with you. They completely kind of ignore the premature ventricular contractions. In fairness, it was a secondary endpoint.
Elizabeth: I would also just like you to comment on cardiac ectopy, just to begin with. My understanding is that everybody has this.
Rick: Exactly. That's why they used the individuals as their own control. Throughout the day, each of us has periods where we have what some people call extra heartbeats. They occur both in the upper chamber, the atrium, and the lower chamber, the ventricle, in a completely normal heart and nothing needs to be done about it.
Elizabeth: Since we're talking about the heart, let's talk about ionizing radiation and cardiovascular disease. That's in the BMJ.
Rick: Now, as a part of the routine care of individuals, they are oftentimes receiving either very moderate or low dose in radiation, mammography or a CT scan, or what's called a myocardial perfusion study -- a nuclear medicine study. Do those low or moderate doses increase the risk of heart disease?
They reviewed over 15,000 studies. They found that there were 93 that they thought were informative. They did look at the risk of heart disease -- ischemic heart disease, stroke, and heart failure -- in relationship to what's considered moderate or low dose. What they did discover is the fact it does increase the risk of heart disease, more so with stroke than ischemic heart disease.
What their estimate was, is that in the U.S. the population base excess absolute risk for heart disease was about 2% to 3% and for England and Wales about 3% to 4%. Where does that lead us? If you need a radiation procedure, use the lowest dose possible. Oftentimes there are alternatives tests that don't provide ionizing radiation. Not always, but sometimes. And if there's not a good indication for it, we really shouldn't be using any ionizing radiation.
Elizabeth: How optimistic are you that we're going to be able to reduce this risk?
Rick: I think we're doing that already. I think we're using a lower radiation doses -- [like] echo. We have MRI, which is non-ionizing radiation.
Elizabeth: Would you say that people, when they are told they need something like this, they ought to ask that question about is there an alternative to this study that would not involve ionizing radiation?
Rick: I think that's an excellent question. Sometimes there is not, Elizabeth. Using the proper scan, the lowest dose of radiation and the maximal duration between scans will be important. All of us that are involved in our own care need to be asking those questions.
Elizabeth: Finally, let's turn to JAMA Internal Medicine. This is an issue that is important to me because I see many patients on the unit where I serve as chaplain who have this condition: delirium. Delirium, of course, very common and especially post-operatively in older adults. It's associated with poor outcomes.
This is a continuation of a study they begun before. What this study is looking at is delirium in older people who have had surgery. This is long-term cognitive decline and incident dementia in this population. This is part of this study that's called the Successful Aging after Elective Surgery (SAGES) study and it began in 2010.
They have 560 community-dwelling older adults -- older than 70 years of age -- who are a part of this. What they assessed was delirium daily during their hospitalization and then they also looked at a number of other measures, general cognitive performance.
They followed these folks up to 6 years of follow-up. Of this number, about 60% of them were women. 24% of them did develop post-operative delirium. They found evidence for differences in acute, post-short term, intermediate, and longer-term change from the day of surgery. Participants with delirium showed significantly faster long-term cognitive change relative to those folks who did not. It was a 40% acceleration in the slope of cognitive decline and they saw that out to 72 months of follow-up.
Rick: In these older individuals -- average age of about 77 -- 24% had delirium. It's such a well-done study as not only did they assess that they had delirium, but then they followed their cognitive function over the course of up to 6 years. What they discovered is, as we age we all develop some cognitive dysfunction, but the decline was greater in those that developed delirium.
Here is the question I pose to you. Is it the delirium that subsequently causes a continued decline over the next 6 or 7 years, or is delirium just a marker of people that are going to develop cognitive decline? If it's the former, then we should try to prevent delirium and try to prevent additional cognitive decline. If it's just a marker, then all you've done is you've identified individuals, and changing the delirium doesn't really change the long-term outcome. What are your thoughts?
Elizabeth: I am reminded of this notion that gestational diabetes is diabetes unmasked -- that in fact you're already at increased risk for developing diabetes and this just turned up at this point because of this additional stressor. The authors also identified that these are people with heightened vulnerability and when those are combined with things such as major surgery, anesthesia, and psychoactive meds, that those things are all potentially that unmasking of this propensity that had already existed.
Rick: Yeah. Elizabeth, I think that's probably the case. I mean, when you look at the two groups of individuals, those that actually had delirium, they were a little bit older, they had a little bit more cognitive dysfunction at baseline. They tried to correct for that in their statistical analysis. In my mind, they just have less reserve. When you put a stressor on them like surgery and anesthesia, put them in a hospital room, make them sleep-deprived, take them out of their natural environment, then they develop delirium. I think it's probably a marker.
Elizabeth: I would also point out that we're doing things, of course, even now to try to reduce the incidence of delirium post-operatively, particularly in older people, like using regional anesthesia rather than general anesthesia, so I think that we're aware.
Rick: I think you're right. Regardless of whether it's the cause or a marker, we want to try to avoid it.
Elizabeth: Very good. 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.