Hvað eru klíniskar rannsóknir?
Í sambandi við rannsóknir þýðir orðið klínískur venjulega að viðkomandi rannsókn sé gerð á fólki, sjúku eða heilbrigðu vegna t.d. vöruþróunnar. Klínískar meðferðarprófanir (e. clinical trials) eru rannsóknir þar sem sjúklingum er slembiraðað (raðað af handahófi) í hópa sem ýmist taka nýja lyfið, eldra lyf eða lyfleysu. Slíkar rannsóknir eru oftast tvíblindar sem þýðir að hvorki sjúklingar né þeir læknar sem meta árangur meðferðarinnar vita hvað hver tekur, en þetta er gert til að minnka hættuna á að sérstakar væntingar eða til dæmis mikil trú á ágæti nýs lyfs hafi áhrif á niðurstöður rannsóknarinnar. Rannsóknir af þessu tagi sem ekki uppfylla skilyrði um slembiröðun og tvíblindun eru venjulega lítils virði. Allar rannsóknir á sjúklingum eru í eðli sínu klínískar. Til viðbótar við lyfjarannsóknir má nefna sem dæmi samanburð á árangri mismunandi skurðaðgerða, samanburð á árangri skurðaðgerða og geislunar og samanburð leitar að efnum í blóði eða þvagi sem hafa forspárgildi fyrir sjúkdóm eða hjálpa til við sjúkdómsgreiningar. Hugtakið klínískar rannsóknir hefur því mjög víðtæka merkingu og felur í sér allar rannsóknir sem gerðar eru á fólki og tengjast sjúkdómum beint eða óbeint. ( Tekið af vefnum: visindavefur.is )
Hér munum við birta hlutlausar klínískar rannsóknir, skýrslur og umræður um rafrettur.
Electronic cigarettes for smoking cessation: a randomised controlled trial
Copyright © 2013 Elsevier Ltd All rights reserved.
Published Online: 09 September 2013
Tilviljunarkennd rannsókn framkvæmd í Nýja Sjálandi frá sept. 2011 til júl 2013. Notast var við rafrettum með og án nikótíns og nikótín plástur. Földi þátttakenda var 651. Rannsóknin var fjármögnuð af „Health Research Council of New Zealand.“
Impact of an Electronic Cigarette on Smoking Reduction and Cessation in Schizophrenic Smokers: A Prospective 12-Month Pilot Study
Caponnetto, P., et al
Published in International Journal of Environmental Research and Public Health, 2013
“We have shown for the first time that the use of e-cigarette substantially decreased cigarette consumption without causing significant side effects in chronic schizophrenic patients who smoke not intending to quit. This was achieved without negative impacts on the symptoms of schizophrenia as assessed by SAPS and SANS symptoms scales.”
Effect of an electronic nicotine delivery device (e cigarette) on desire to smoke and withdrawal, user preferences and nicotine delivery: randomised cross-over trial
Bullen, C., et al
Published in Tobacco Control, 2010
“The 16 mg Ruyan alleviated desire to smoke after overnight abstinence, was well tolerated and had a pharmacokinetic profile more like the Nicorette inhalator than a tobacco cigarette. Evaluation of the ENDD for longer-term safety, potential for long-term use and efficacy as a cessation aid is needed. Trial registration No.12607000587404, Australia and New Zealand Clinical Trials Register.”
A Clinical Laboratory Model for Evaluating the Acute Effects of Electronic “Cigarettes”: Nicotine Delivery Profile and Cardiovascular and Subjective Effects
Vansickel, A.R., et al
Published in Cancer Epidemiology, Biomarkers & Prevention, 2010
“This study illustrates how clinical laboratory methods can be used to understand the acute effects of these and other PREPs for tobacco users. The results and methods reported here will likely be relevant to the evaluation and empirically based regulation of electronic cigarettes and similar products.”
Caponnetto P, Cibella F, Mancuso S, Campagna D, Arcidiacono G, Polosa R. Effect of a nicotine free inhalator as part of a smoking cessation program. Eur Respir J. 2011 May 12.
Smoking-cessation drugs are inadequate at addressing the behavioural component of tobacco dependence. This study assessed the effect of using a nicotine-free inhalator to improve success in a cessation programme. Nicotine-free inhalators may be beneficial when used in the context of smoking-cessation interventions, particularly for those smokers for whom handling and manipulation of their cigarettes plays an important part in the ritual of smoking.
Darredeau C, Campbell M, Temporale K, et al. Subjective and reinforcing effects of electronic cigarettes in male and female smokers. 12th annual meeting of the Society for Research on Nicotine and Tobacco
Europe. Bath, UK, 2010.
Dawkins L, Turner J, Hasna S, Soar K. The electronic-cigarette: Effects on desire to smoke, withdrawal symptoms and cognition.
Addict Behav. 2012 Aug;37(8):970-3.
Goniewicz ML, Gawron M, Peng M, et al. Electronic cigarettes deliver similar levels of nicotine and reduce exposure to combustion toxicants after switching from tobacco cigarettes. Society for Research on Nicotineand Tobacco 18th Annual Meeting. Houston, Texas, USA, 2012. Page 40:
Polosa R, Caponnetto P, Morjaria J B, Papale G, Campagna D, Russo C: Effect of an Electronic Nicotine
Delivery Device (e-Cigarette) on Smoking Reduction and Cessation: A Prospective 6-Month Pilot Study.
BMC Public Health 2011, 11:786.
Rodu B. The scientific foundation for tobacco harm reduction, 2006-2011. Harm Reduct J. 2011 Jul 29;8:19.
Rose JE, Turner JE, Murugesan T, Behm FM. Pulmonary delivery of nicotine pyruvate: sensory and pharmacokinetic characteristics. Poster, Society for Research on Nicotine and Tobacco 16th annual
conference, Baltimore, 27 February 2010.
Vansickel AR, Weaver MF, Eissenberg T. Clinical laboratory assessment of the abuse liability of an electronic cigarette. Addiction. 2012 Jan 9.
Acute effect of e-cigarette on pulmonary function in healthy subjects and smokers
Gennimata, S.A., et al
Abstract presented at ERS Congress, Vienna, 2012
The results of this study, which found that electronic cigarettes have “a measurable effect that lasts ten minutes”, were reported – by one of the lead authors, Professor Christina Graziou – as “can cause immediate harm”.
This ‘research’ was widely criticised:
Professor M Siegel: “Experts” from University of Athens Tell the Public They Are Not Sure if Smoking is Any More Hazardous than Vaping. Despite Lack of Demonstration of Clinically Significant Effects on Airways and Improvements in Respiratory Symptoms in Many Vapers
Professor M Siegel: European Respiratory Society Publicly Claims that Electronic Cigarettes Cause Cancer and Lies About Tobacco Industry Involvement in Creation of These Products
Dr Carl Phillips: Christina Gratziou is a liar
American Council on Science and Health: E-Cigarette study is just amateur propaganda
Granger, J. & Cornette, B.
- Unpublished to date.
“- 64% of the persons having used the electronic cigarette noticed positive effects on their health. 15% indicated minor side effects (mouth, lips or throat irritated).
– Over the 3 months, the heart rhythm of the participants decreased.
– The level of exhaled carbon monoxide (CO) decreased in every case and reduced to nil/zero for vapers having stopped smoking.
– Weight gain was moderated. In cases of complete smoking cessation with continuation of vaping, weight gain was less than is usually noticed following smoking cessation.
– The forced vital capacity (FVC) improved with the use of the electronic cigarette, especially when there was significant reduction or total cessation of smoking.
– The maximum expiratory pressure per second (MEPS) was stable or improved slightly with the use of the electronic cigarette.”
(The above was taken from our own translation of the study, which French colleagues have confirmed is accurate. The full translation is available from the ECITA blog.)
Etter, J.F., & Bullen, C.
Published in Addiction, 2011
“Findings. There were 3587 participants (70% former tobacco smokers, 61% men, mean age 41 years). The median duration of electronic cigarette use was 3 months, users drew 120 puffs/day and used 5 refills/day. Almost all (97%) used e-cigarettes containing nicotine. Daily users spent $33 per month on these products. Most (96%) said the e-cigarette helped them quit smoking or reduce their smoking (92%). Reasons for using the e-cigarette included the perception it was less toxic than tobacco (84%), to deal with craving for tobacco (79%) and withdrawal symptoms (67%), to quit smoking or avoid relapsing (77%), because it was cheaper than smoking (57%) and to deal with situations where smoking was prohibited (39%). Most ex-smokers (79%) feared they might relapse to smoking if they stopped using the e-cigarette. Users of nicotine-containing e-cigarettes reported better relief of withdrawal and a greater effect on smoking cessation than those using non-nicotine e-cigarettes.
Conclusions. E-cigarettes were used much as people would use nicotine replacement medications: by former smokers to avoid relapse or as an aid to cut down or quit smoking. Further research should evaluate the safety and efficacy of e-cigarettes for administration of nicotine and other substances, and for quitting and relapse prevention.”
Caponnetto, P., Polosa, R., Auditore, R., Russo, C., & Campagna, D.
Published in the International Journal of Clinical Medicine, 2011
“This is the first time that objective measures of smoking cessation are reported for smokers who quit successfully after using an E-cigarette. This was accomplished in smokers who repeatedly failed in previous attempts with professional smoking cessation assistance using the usual nicotine dependence treatments and smoking cessation counselling.”
Farsalinos, K., et al.
Presented at ESC Congress, 2012. Unpublished to date.
“Haemodynamics: significant elevation in blood pressure and heart rate (+8% in systolic, +6% in diastolic, +10% in heart rate) after smoking
Slight elevation of diastolic blood pressure alone (+4%) after electronic cigarette use
Cardiac function: diastolic function acutely impaired in smokers (4 parameters adversely affected), in agreement with previous studies
No difference in diastolic function observed after electronic cigarette use
Less nicotine absorbed (Bullen et al, Tob Control 2010)
Absence of combustion and different chemical composition, leading to less toxic chemicals created and absorbed.”
Vansickel, A.R., & Eissenberg, T.
Published in Nicotine and Tobacco Research, Oxford Journals, 2012
“User experience and/or device characteristics likely influence EC nicotine delivery and other effects. Systematic manipulation of these and other variables could elucidate conditions that produce intended effects.”