Complex Things Explained
December 23, 2013 1:54 PM   Subscribe

This Video Will Hurt
A detailed explanation of a fascinating field of science and medicine by the always interesting C.G.P. Grey.

Protean nature of mass sociogenic illness: From possessed nuns to chemical and biological terrorism fears [FULL TEXT HTML]
Background: Episodes of mass sociogenic illness are becoming increasingly recognised as a significant health and social problem that is more common than is presently reported.
Aims: To provide historical continuity with contemporary episodes of mass sociogenic illness in order to gain a broader transcultural and transhistorical understanding of this complex, protean phenomenon.
Method: Literature survey to identify historical trends.
Results: Mass sociogenic illness mirrors prominent social concerns, changing in relation to context and circumstance. Prior to 1900, reports are dominated by episodes of motor symptoms typified by dissociation, histrionics and psychomotor agitation incubated in an environment of preexisting tension. Twentieth-century reports feature anxiety symptoms that are triggered by sudden exposure to an anxiety-generating agent, most commonly an innocuous odour or food poisoning rumours. From the early 1980s to the present there has been an increasing presence of chemical and biological terrorism themes, climaxing in a sudden shift since the 11 September 2001 terrorist attacks in the USA.
Conclusions: A broad understanding of the history of mass sociogenic illness and a knowledge of episode characteristics are useful in the more rapid recognition and treatment of outbreaks.

Are some people sensitive to mobile phone signals? Within participants double blind randomised provocation study [FULL TEXT HTML]
Objective: To test whether people who report being sensitive to mobile phone signals have more symptoms when exposed to a pulsing mobile signal than when exposed to a sham signal or a non-pulsing signal.
Design: Double blind, randomised, within participants provocation study.
Setting: Dedicated suite of offices at King's College London, between September 2003 and June 2005.
Participants: 60 “sensitive” people who reported often getting headache-like symptoms within 20 minutes of using a global system for mobile communication (GSM) mobile phone and 60 “control” participants who did not report any such symptoms.
Intervention: Participants were exposed to three conditions: a 900 MHz GSM mobile phone signal, a non-pulsing carrier wave signal, and a sham condition with no signal present. Each exposure lasted for 50 minutes.
Main outcome measures: The principal outcome measure was headache severity assessed with a 0-100 visual analogue scale. Other outcomes included six other subjective symptoms and participants' ability to judge whether a signal was present.
Results: Headache severity increased during exposure and decreased immediately afterwards. However, no strong evidence was found of any difference between the conditions in terms of symptom severity. Nor did evidence of any differential effect of condition between the two groups exist. The proportion of sensitive participants who believed a signal was present during GSM exposure (60%) was similar to the proportion who believed one was present during sham exposure (63%).
Conclusions: No evidence was found to indicate that people with self reported sensitivity to mobile phone signals are able to detect such signals or that they react to them with increased symptom severity. As sham exposure was sufficient to trigger severe symptoms in some participants, psychological factors may have an important role in causing this condition.

Adverse events attributable to nocebo in randomized controlled drug trials in fibromyalgia syndrome and painful diabetic peripheral neuropathy: systematic review. [ABSTRACT - PAYWALL]
OBJECTIVE: The objectives of the study were to determine the impact of nocebo effects on adverse events (AEs) in drug trials in fibromyalgia syndrome (FMS) and painful diabetic peripheral neuropathy (DPN).
METHODS: MEDLINE, CENTRAL, SCOPUS, and the databases of the U.S. National Institutes of Health and the Pharmaceutical Research and Manufacturers of America were searched until December 31, 2010. Randomized controlled trials with a parallel design of any drug therapy compared with pharmacological placebo in patients with FMS and DPN were included. Pooled estimates of nocebo effects (number of patients with at least 1 AE and dropping out due AEs) were calculated for placebo and true drug groups by a random effects model.
RESULTS: Fifty-eight FMS (62 DPN) trials included a total of 5065 (5095) patients in placebo groups. The quality of reporting the assessment strategy of AEs was poor in most trials. The pooled estimate of the event rate drop out rate due to AEs in placebo groups was 9.6 [95% confidence control (CI): 8.6-10.7] in placebo and 16.3 (95% CI: 14.1-31.2) in true drug groups of FMS trials and was 5.8 (95% CI: 5.1-6.6) in placebo and 13.2 (95% CI: 10.7-16.2) in true drug groups of DPN trials. Nocebo effects accounted for 72.0% (44.9) of the drop outs in true drug groups in FMS (DPN).
DISCUSSION: Nocebo effects substantially accounted for AEs in drug trials of FMS and DPN. Standards to assess and report AEs should be defined by regulatory agencies. Strategies to minimize nocebo effects in both clinical trials and clinical practice should be developed.

Nocebo-induced hyperalgesia during local anesthetic injection. [FULL TEXT BEHIND FREE REGISTRATION]
Common practice during local anesthetic injection is to warn the patient using words such as: "You will feel a big bee sting; this is the worst part." Our hypothesis was that using gentler words for administration of the local anesthetic improves pain perception and patient comfort. One hundred forty healthy women at term gestation requesting neuraxial analgesia were randomized to either a "placebo" ("We are going to give you a local anesthetic that will numb the area and you will be comfortable during the procedure") or "nocebo" ("You are going to feel a big bee sting; this is the worst part of the procedure") group. Pain was assessed immediately after the local anesthetic skin injection using verbal analog scale scores of 0 to 10. Median verbal analog scale pain scores were lower when reassuring words were used compared with the harsher nocebo words (3 [2-4] vs 5 [3-6]; P < 0.001). Our data suggest that using gentler, more reassuring words improves the subjective experience during invasive procedures.

Are media warnings about the adverse health effects of modern life self-fulfilling? An experimental study on idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF) [ABSTRACT - PAYWALL]
Objective: Medically unsubstantiated ‘intolerances’ to foods, chemicals and environmental toxins are common and are frequently discussed in the media. Idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF) is one such condition and is characterized by symptoms that are attributed to exposure to electromagnetic fields (EMF). In this experiment, we tested whether media reports promote the development of this condition.
Methods: Participants (N = 147) were randomly assigned to watch a television report about the adverse health effects of WiFi (n = 76) or a control film (n = 71). After watching their film, participants received a sham exposure to a WiFi signal (15 min). The principal outcome measure was symptom reports following the sham exposure. Secondary outcomes included worries about the health effects of EMF, attributing symptoms to the sham exposure and increases in perceived sensitivity to EMF.
Results: 82 (54%) of the 147 participants reported symptoms which they attributed to the sham exposure. The experimental film increased: EMF related worries (β = 0.19; P = .019); post sham exposure symptoms among participants with high pre-existing anxiety (β = 0.22; P = .008); the likelihood of symptoms being attributed to the sham exposure among people with high anxiety (β = .31; P = .001); and the likelihood of people who attributed their symptoms to the sham exposure believing themselves to be sensitive to EMF (β = 0.16; P = .049).
Conclusion: Media reports about the adverse effects of supposedly hazardous substances can increase the likelihood of experiencing symptoms following sham exposure and developing an apparent sensitivity to it. Greater engagement between journalists and scientists is required to counter these negative effects.

Spatio-temporal differences in the history of health and noise complaints about Australian wind farms: evidence for the psychogenic, “communicated disease” hypothesis. [FULL TEXT PDF]
Background and objectives With often florid allegations about health problems arising from wind turbine exposure now widespread in parts of rural Australia and on the internet, nocebo effects potentially confound any future investigation of turbine health impact. Historical audits of health complaints across periods when such claims were rare are therefore important. We test 4 hypotheses relevant to psychogenic explanations of the variable timing and distribution of health and noise complaints about wind farms in Australia. Setting All (n=51) Australian wind farms (with 1634 turbines) operating from 1993–2012 . Methods Records of complaints about noise or health obtained from wind farm companies regarding residents living near 51 Australian wind farms, expressed as proportions of estimated populations residing within 5km of wind farms, and corroborated with complaints in submissions to 3 government public enquiries and news media records and court affidavits . Results There are large spatio-temporal variations in wind farm noise and health complaints.33/51(64.7%) of Australian wind farms including 17/34(50%) with turbine size >1MW have never been subject to noise or health complaints. These 33 farms have some 21,592 residents within 5km of their turbines and have operated complaint-free for a cumulative total of 267 years. Western Australia and Tasmania Have seen no complaints. Only 131 individuals across Australia representing approximately 1 in 250 residents living within 5km of wind farms appear to have ever complained, with 94(72%) of these being residents near 6 wind farms which have been targeted by anti wind farm groups . About 1 in 87 (126/10901) of those living near turbines >1MW have ever complained. The large majority 104/131(79%) of health and noise complaints commenced after 2009 when anti wind farm groups began to add health concerns to their wider opposition. In the preceding years, health or noise complaints were rare despite large and small turbined wind farms having operated for many years. Conclusions In view of scientific consensus that the evidence for wind turbine noise and infrasound causing health problems is poor, the reported spatio-temporal variations in complaints are consistent with psychogenic hypotheses that health problems arising are “communicated diseases” with nocebo effects likely to play an important role in the aetiology of complaints.

Thyroxine: anatomy of a health scare [FULL TEXT AFTER FREE 14 DAY TRIAL]
Hypothyroidism is a common medical disorder that is easily managed by replacement treatment with synthetic thyroxine. About 70 000 New Zealanders have hypothyroidism and take thyroxine replacement treatment. Since 1973 the only thyroid hormone replacement drug approved and funded by the government for use in New Zealand was the Eltroxin brand, made by GlaxoSmithKline. In 2007 the company moved the manufacture of Eltroxin from Canada to Germany. This resulted in a change in the tablets’ inert ingredients: the new formulation differed in markings, size, and colour and—according to some reports—also in taste and rate of dissolution on the tongue. The active ingredient (thyroxine) remained unchanged and continued to be made in Austria.
In 2007 and 2008 New Zealand pharmacies changed to the new formulation of Eltroxin. The old formulation had been used for more than 30 years without problems; but after the new tablets were introduced the rate of adverse event reporting rose nearly 2000-fold—from 14 reports in 30 years to more than 1400 in 18 months. What had happened? And does this incident provide important lessons for future formulation changes and migration to generic drugs?

Disease-specific adverse events following nonlive vaccines: a paradoxical placebo effect or a nocebo phenomenon? [ABSTRACT - PAYWALL]
Vaccines can cause adverse reactions (AR), i.e. adverse events following immunization (AEFIs) due to the vaccine, such as local reactions or fever. In addition, live attenuated vaccines which replicate in vaccinees can cause disease-specific AR, e.g. measles-like rash following measles vaccination. However, nonlive vaccines because they are inactivated and they do not replicate in vaccinees, are not likely to cause disease-specific AR. The aim of the study was to assess whether safety signals could be generated by an undescribed bias in spontaneous reporting of disease-specific AEFIs with nonlive vaccines. All AEFIs of Sanofi Pasteur MSD vaccines spontaneously reported in France from January 2000 to June 2010, coded according to MedDRA terms and collected in the company's pharmacovigilance database were analyzed. Vaccine-event pairs of interest were selected a priori. The disproportionality reporting rate methodology was used, comparing the proportion of a given event reported following a given vaccine to its proportion reported following all other studied vaccines. The Reporting Odds Ratio (ROR) was used for signals detection for each vaccine-event pair selected. A total of 33,275 AEFIs were analyzed. The calculated ROR showed a statistically disproportionate reporting rate and generated false safety signals for almost all the pairs tested. Three nonlive vaccine pairs were striking: gynaecological symptoms and the quadrivalent human papillomavirus (qHPV) vaccine; trismus and tetanus vaccines; hepatobiliary disorders and hepatitis B vaccines. In conclusion we have identified a new vaccine AE spontaneous reporting bias: "disease-specific adverse events following nonlive vaccines", showing that vaccinees and healthcare professionals tend to report preferentially the symptoms of the disease against which the nonlive vaccine was administered. We suggest that bias is subordinate to a paradoxical placebo effect and/or a nocebo phenomenon.

Mass Psychogenic Illness Attributed to Toxic Exposure at a High School [FULL TEXT HTML]
BACKGROUND: Mass psychogenic illness may be difficult to differentiate from illness caused by bioterrorism, rapidly spreading infection, or toxic substances. We investigated symptoms attributed to exposure to toxic gas at a high school in Tennessee.
METHODS: In November 1998, a teacher noticed a “gasoline-like” smell in her classroom, and soon thereafter she had a headache, nausea, shortness of breath, and dizziness. The school was evacuated, and 80 students and 19 staff members went to the emergency room at the local hospital; 38 persons were hospitalized overnight. Five days later, after the school had reopened, another 71 persons went to the emergency room. An extensive investigation was performed by several government agencies.
RESULTS: We were unable to find a medical or environmental explanation for the reported illnesses. The persons who reported symptoms on the first day came from 36 classrooms scattered throughout the school. The most frequent symptoms (in this group and the group of people who reported symptoms five days later) were headache, dizziness, nausea, and drowsiness. Blood and urine specimens showed no evidence of carbon monoxide, volatile organic compounds, pesticides, polychlorinated biphenyls, paraquat, or mercury. There was no evidence of toxic compounds in the environment. A questionnaire administered a month later showed that the reported symptoms were significantly associated with female sex, seeing another ill person, knowing that a classmate was ill, and reporting an unusual odor at the school.
CONCLUSIONS: This illness, attributed to toxic exposure, had features of mass psychogenic illness — notably, widespread subjective symptoms thought to be associated with environmental exposure to a toxic substance in the absence of objective evidence of an environmental cause.
posted by Blasdelb (7 comments total) 33 users marked this as a favorite
 
I watched "This Video Will Hurt", and thought it was informative and just great.

But...

"You know how I told you to end your videos one half of a sentence earlier?"
posted by tigrrrlily at 2:59 PM on December 23, 2013


I wonder if they intended for that high pitched sound at the start to be audible, or if I'm just awesome.
posted by ZaneJ. at 3:14 PM on December 23, 2013 [1 favorite]


No, It was audible. I kept thinking "There is no way this is going to work." And promptly watched the entire video. Good use of a beat there video producers.

Otherwise, interesting topic. I have seen this "epedemic" sweep through my office and have wondered how much was the Nocebo effect.
posted by Benway at 4:31 PM on December 23, 2013


The high pitched note you hear at around 12 seconds is approximately 11112 Hz, far within the usual range of human hearing. Moreover, the AAC encoder that was used appears to have a lowpass cutoff at 17250 Hz, which seems to be par for the course for a 192 kbps bitrate which is what youtube uses for 1080p streams. (And even without such an implementation detail, there's a hard Nyquist limit at 22.05 kHz due to the 44.1 kHz sample rate.)
posted by Rhomboid at 10:11 PM on December 23, 2013 [1 favorite]


Come see NOCEBO, one night only, with special guests BIG SCIENCE MACHINE and DRAMA LLAMA. Doors open at 8!
posted by tonycpsu at 10:18 PM on December 23, 2013


Anytime a video starts with "put on your headphones I promise I won't play any loud sounds" I turn it off. Even CGP Grey.
posted by Cyclopsis Raptor at 9:40 AM on December 24, 2013


I thought the "anti-nocebo drug" was meant to be a placebo, but apparently not? There's a chemical that blocks the effect? I mean, I guess you might simply use anaesthetics...
posted by LogicalDash at 5:24 AM on December 25, 2013


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