I hate studies like this. The researchers controlled for age, sex, body mass index, race, deprivation, family history of hypertension, education, smoking status, blood pressure, blood lipids, inflammation, blood glucose, kidney function and use of medications to lower cholesterol or blood glucose levels. But there are a million other potential causal factors that could be correlated with talking on the phone. For instance, stressors in your life can be a reason to talk on the phone, and stress is linked with hypertension. I think these types of studies can be fine if it's clear that this is just a correlation, but the researchers seem to be presenting this as if they've established a causal relationship.
> Professor Qin said: “Our findings suggest that talking on a mobile may not affect the risk of developing high blood pressure as long as weekly call time is kept below half an hour. More research is required to replicate the results, but until then it seems prudent to keep mobile phone calls to a minimum to preserve heart health.”
I really wish more work was done to establish a causal relationship before publishing something like this.
Anything that is less than double-blind is essentially a well documented hunch. In some situations this enough to merit action. This study is interesting enough to merit more science to build stronger evidence.
Merits of this study:
* It was large, twelve years and over 200,000 participants.
* The impact was dose responsive. People that reported talking longer on the phone had greater chances of hypertension.
* The impact is large enough to cause concern.
* In the published article, a mechanism of action was purposed (RF-EMF), and other studies related to this mechanism were cited.
* It fits the expected amount of 'controlling for' third variables you would expect, even if we cannot control for everything.
Weaknesses of this study:
* Mobile usage was self reported. Using empirical data such as cellphone bills or data from cellphone would have been much more accurate. There could be a bias where those with higher blood pressure perceive themselves as talking on mobile more frequently.
* There was no determination of the nature of the calls. Personally, my blood pressure feels very different when I talk to family for 30 minutes than if I'm talking to Comcast for 30 minutes.
* About 3/5 of the study participants dropped out. We'd expect lots of dropouts to occur with such a long study, but it could skew the data if dropouts had some statistical significance on measured values and weren't random. Dropouts are almost never random.
* The article admits those with mobile phone usage seem to be at a higher natural disposition for hypertension. More likely to smoke, many other high variables. It seems plausible that some other risk factors were associated with that cluster that did not get accounted for.
* No direct measurement of the purposed mechanism of action was performed.
> There was no determination of the nature of the calls. Personally, my blood pressure feels very different when I talk to family for 30 minutes than if I'm talking to Comcast for 30 minutes.
In my opinion that's the explanation. Even if not considering the extremes you mentioned, the more you're interrupted the less relaxed you are. The metric here is minutes talked but they're probably linear with the number of unexpected calls.
Yeah, it seems highly unlikely. Having to talk a lot on the phone gives me stress. It's odd they don't even mention the most probably reason for their finding, and invent some unproven theory about emf affecting blood pressure. The only study I can find is this:
Sure, but, like the drop outs, all human behavior is correlated with a million other things. Myself and others have mentioned stress as a possible factor, but there are likely random things you wouldn't even think of like: people who use the phone more are more likely to talk to telemarketers, and talking to telemarketers is correlated with lower intelligence, and lower intelligence is correlated with eating more salt. I'm not suggesting that as a possible cause, just illustrating how complicated the true causal relationship could be. I think it's really a stretch to treat this study as establishing a causal relationship. There are also some open questions like why other types of phone usage don't seem to trigger this effect (the author mentions other studies purely on smartphone use have been inconsistent).
If the authors really believe RF-EMF can cause hypertension, then this study is a fine first step. But they really should find a way to test the mechanism of action before saying they've found a causal relationship.
I think this goes a long way towards making an argument that RF-EMF is a plausible risk factor for hypertension. I'd ideally like to see some follow up studies. Some rat model studies. Some humans with other increased RF-EMF exposure also having higher risks. There is a long distance between providing "any" evidence and "found a casual relationship", so I feel a bit like the goalpost is moving.
Even if RF-EMF isn't the cause, the effect is large enough that it begs the question "Why", which is where the other possible factors suggested come in.
It begs the question "Why", but I think there's already a few very plausible possibilities (more plausible than RF-EMF in my opinion).
In my mind, increased calls are linked with increased cases of emergencies (because much communication is done through text chat and equivalents), so calls are for when that's not sufficient or for when people are away from their normal groups for extended periods. Both of those tend to induce stress. Does stress increasing hypertension account for this?
> Anything that is less than double-blind is essentially a well documented hunch.
Not true! Economists have devoted person-millenia developing the theory of instrumental variables, which lets you extract causal relationships from historical non-experimental data.
That said, it's damn hard to find a good instrument. Many economists use it badly, and most doctors don't even know the theory.
I have my doubts about IVs in practice, but I agree they theoretically are an acceptable substitute.
The problem is we conduct science on systems we don't fully understand. Because we don't fully understand it, it's easy to miss important information we didn't know is important.
The double blind with random selection allows us to control for all important information, determine causation, and is the best known method for controlling for bias. We don't have to worry about missing important variables because the nature of random selection means those variables are randomly distributed.
When possible, experiments are better, yes. But that should not cause us to give up hope for causal information in areas where experiments are impossible.
>But there are a million other potential causal factors that could be correlated with talking on the phone.
This is basically the logic that cigarette companies used to deny that they were causing lung cancer. A longitudinal study is about as good as you can get for testing these sort of hypotheses.
No. That was the mechanism the cigarette companies used to deny they were causing heart disease. It turns out there’s really no such thing as a Type A personality. Those were just smokers.
Yeah I imagine the average dosage of RF across populations has been increasing enough overtime along with rollout of new technologies that you’d be able to correlate some function of adoption of these technologies to population level effects if there was any real significance.
Hands free being what? Keeping using the speaker and setting the phone on a table? Using Bluetooth ear plugs with the phone in a breast pocket? So much we don't know...
Yikes. Yeah I'm of two minds about things like this. Usually it is meant to provide some interesting data for follow-up studies, so it has to be published.
But until the actual science is performed by making this recommendation and tracking the results, there's no advice or conclusion that can be drawn from stuff like this. We need more science literacy --in journalism--.
Yes and no. I understand that a causal relationship is the goal, but short of an experimental design, anything done is going to have similar holes punched through it. My view, as others have noted, is that this is a just one correlation. I'll feel that it's more causal once we see it pop up again and again in different studies, with different populations, controls, analyses, timescales, etc. It's ok to document correlations, but researchers need to temper their language when discussing correlation studies in general.
The researchers analysed the relationship between mobile phone usage and new-onset hypertension after adjusting for age, sex, body mass index, race, deprivation, family history of hypertension, education, smoking status, blood pressure, blood lipids, inflammation, blood glucose, kidney function and use of medications to lower cholesterol or blood glucose levels.
But not having a job or a family member that calls you with stressful crap?
How about being on hold, listening to repetitive music interspersed with a recorded "you are x in the queue, we'll be with you shortly" in a precisely-calculated interval to get your hopes up then immediately crush them, efficiently fanning the flames of rage as the minutes and hours pass.
I think there’s definitely something to this, and it’s insidious because the technological ability to reach someone at any time has built social expectations accordingly. Everyone is reachable all of the time, and the threshold for agitation when someone cannot be reached has never been shorter.
I like to spend time in the wilderness, and I’ve thought a lot about this concept of “reachability” and how it contributes to the kind of unique feeling I have when I’m deep in the backcountry.
Over time technology has increased the percentage of the day where someone is reachable: home phones became ubiquitous, then answering machines, then cell phones with limited coverage, now cell phones with extremely broad coverage, even on airplanes. Accordingly, most people now assume they can get ahold of you basically whenever. You can try to manage people’s expectations as an individual, but you will be swimming against the current.
I think being unreachable sometimes is healthy. Heading into the backcountry with no cell service is an incredibly freeing feeling for me, and one I think many people simply never feel these days.
I just leave my cellphone places on purpose. Later I call them back with an excuse like "Sorry, I left my phone in the kitchen and was at my desk." Anyone that calls me regularly knows to expect this. I do keep my phone on and near me during standard business hours, but even then I might not answer a family call and give a work excuse.
I'm not taking the work phone anywhere I don't have to, that's for sure. I get to them when/if I feel it's appropriate. I've had zero problems there so far.
I don't always have MY phone on me either, and even if I do I don't always answer.
It is this phone where I have the biggest problem with people and boundaries. Sometimes I feel like I'm surrounded by needy children but they're in their 40s, 50s, and 70s.
A phone call, a voice mail, a call back, another voice mail to remind me about the first call, maybe a call that night too. Nobody even died. It's not always the same person either.
So the next call I do answer will be mostly a shaming about how I don't answer the phone. You're right and your behavior right now is why. Have a nice day mom.
Does it sound stressful? I don't care probably even as much as I should, but one day it will be something important but the boy cried wolf too many times and got eaten.
Just remember. If you have them, teach your kids that while they may be the main character in their story, they are not the main character in the story, and the difference between the two.
> researchers analysed the relationship between mobile phone usage and new-onset hypertension after adjusting for age, sex, body mass index, race, deprivation, family history of hypertension, education, smoking status, blood pressure, blood lipids, inflammation, blood glucose, kidney function and use of medications to lower cholesterol or blood glucose levels
Seriously? No control for non-mobile phone use, or even using a headset (i.e. not raising your arm)?
> seems like that would be hard to control for over such a long period of time
Controlling for those over six months with a smaller sample would yield a more-meaningful result. This study fails to rule out the hypothesis that getting calls correlates with hypertension, which neighbours stress causes hypertension, which we know. (I am trying to find the study, because a quote near the top cites hands-free use.)
My thought as well. Anecdotes but there's a very high correlation in my environment of people working 12+ hours a day, having high blood pressure and spending most of that time on the phone putting out fires or keeping up-to-date. With that said, I'm sure some of them would benefit personally from less phone use and just isolate themselves a bit from what's going on in the business.
Reading the article, I failed to see what link they found. The headline here matches the one on the article so I'm not calling that into question, but what seems to be more accurate is "Mobile phone calls correlated with increased risk of high blood pressure" since no actual causal link is established. The article repeatedly calls it out as a link as well. It'd be easy for certain groups to fill in the blanks and claim this proves mobile radiation is a health risk, while it doesn't at all establish that causal link. Just as easily, it could be inferred that longer calls are more stressful. And also just as easily the link could be established that those with a family history of hypertension or have other risk factors are more likely to have longer phone conversations.
So I'd argue there's no established link, but there might be an obvious correlation that might warrant more study.
So the article mentions:
"... suggested that long-term exposure to radio-frequency electromagnetic fields (RF-EMF) emitted by mobile phones was related to oxidative stress, increased inflammation, and DNA damage, all of which could lead to the development of hypertension."
I'd assume that talking through DECT or WiFi has similar effects, which would mean that there is no safe way to phone wirelessly longer then 30 minutes a day. Should I put my aging mother on a wired phone and internet connection just to be on the safe side? Or is that tinfoil hat territory?
my thoughts as well. with digital compression, words cutting out, and trying to decipher what the other person's saying without looking at them, mobile phone calls just require a lot of cognitive load from me in general.
I do find it easier to understand when I'm looking directly at them in-person, partly because I can infer a lot of meaning from their facial expressions and match what I'm hearing to how their mouth is moving.
not to mention that almost all of my phone calls fall into two categories: calling my family to catch up, and calling services to wait on hold and deal with an underpaid support rep on the other end. category 2 is almost always stressful and irritating in and of itself, and would be similarly stressful (albeit less so) if I went to their location in-person to deal with the support issue.
This study would be a lot more credible if they asked about cell phone use on follow up and then differenced everyone against their prior reporting, to determine if *changes* in cell phone use (and other control factors that might change over time) increased risk of hypertension. Still not perfect because of the long time lag to follow up, but much better. Either they didn’t know to do this or they did but then didn’t find the desired results… either way, not a good look.
I get anxious anytime someone actually calls me, because (aside from two of my friends), the only time someone is calling me rather than texting is when there's an actual emergency happening.
Ironically, video calls use more bandwidth yet are cheaper (for voice calls using the standard phone dialing functionality I mean, I don't know too much about plain old voice calls over wifi and their cost structure)
> Professor Qin said: “Our findings suggest that talking on a mobile may not affect the risk of developing high blood pressure as long as weekly call time is kept below half an hour. More research is required to replicate the results, but until then it seems prudent to keep mobile phone calls to a minimum to preserve heart health.”
I really wish more work was done to establish a causal relationship before publishing something like this.