Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Indicators for risk of heart disease are higher in passive smokers

13.02.2007
Exposure to second-hand smoke at work, home or elsewhere results in a disproportionate rise in markers that increase the risk of cardiovascular disease, University of Nottingham researchers have found.

A new study published in Circulation, a journal of the American Heart Association, measured the level of cotinine in participants’ blood, rather than relying on participants’ self-reporting of exposure to second-hand smoke. Cotinine is the major metabolite of nicotine that indicates levels of nicotine intake.

Since nicotine is highly specific for tobacco smoke, blood serum cotinine levels track exposure to tobacco smoke and its toxic components.

Dr Andrea Venn, lead author of the study and associate professor in the Division of Epidemiology and Public Health at The University of Nottingham, said: “Our study provides further evidence to suggest low level exposure to second-hand smoke has a clinically important effect on susceptibility to cardiovascular disease.

“This is the first epidemiological study to relate the levels of these markers to an objective measure of second-hand smoke exposure, rather than self-reported exposure, which can be biased.”

Dr Venn and co-author Professor John Britton checked to see if people exposed to second-hand smoke had increased levels of fibrinogen, homocysteine and C-reactive protein — all markers of cardiovascular disease. Researchers examined data from the third National Health and Nutrition Examination Survey (NHANES III, 1988–94), which included 7,599 adults who had never smoked.

Sixty-eight percent of the participants were women, with participants’ median age being 38. Eighteen percent of participants had no detectable levels of cotinine; the rest were classified as having either low or high cotinine. Eighteen percent of participants with low levels of cotinine and 56 percent of subjects with high levels of cotinine reported living with a smoker at home or being exposed to tobacco smoke at work, the primary places for long-term exposure.

Researchers found the low- and high-cotinine groups had significantly higher levels of fibrinogen and homocysteine than the ‘no detectable’ group, with fibrinogen levels estimated at 9–10 milligrams per decilitre higher and homocysteine levels at 0.8 micromoles per litre higher.

Dr Venn said: “The increased levels of fibrinogen and homocysteine seen in relation to second-hand smoke exposure were equivalent to about 30 per cent to 45 per cent of those seen for active smoking.”

The researchers also investigated elevated C-reactive protein, another inflammatory marker, and white blood cell count in participants with elevated cotinine levels. They found no significant association.

The effect levels seen for fibrinogen and homocysteine were about twice as high when measuring cotinine levels compared to previous studies based on self-reported exposure.

The association changed little even after researchers adjusted for participants’ self-reported fruit and vegetable consumption — one of the more influential aspects of diet on cardiovascular health — and for lifestyle factors such as physical activity, social class and obesity. Restricting analysis to those 70 or younger with no history of heart attack, heart failure or stroke also made little difference in the association.

Dr Venn said: “Our study shows that very low levels of exposure to second-hand smoke may be associated with appreciable increases in cardiovascular risk. While the cotinine levels were on average only about 0.1 percent of those in active smokers, the apparent effects of passive smoking on the biomarkers were about one-third to one-half those for active smoking.”

The associations with fibrinogen and homocysteine observed in the study translate into an increase in a disease risk of five per cent, although the combined effect due to other processes is likely to be closer to 30 percent, Dr Venn said.

“Even when participants weren’t exposed to smoke at the workplace or at home, many had low or high levels of cotinine in their blood,” Dr Venn said. “These people may be exposed in bars or restaurants or perhaps in other people’s homes such as those of relatives or friends. This suggests that even people exposed to low levels of second-hand smoke may be at increased risk.

“This study supports existing evidence that exposure to second-hand smoke is an important avoidable cause of cardiovascular disease. It also highlights the importance of implementing measures to protect the public from second-hand smoke such as banning smoking in enclosed public places and workplaces,” Dr Venn added.

A smoking ban applying to all UK public spaces comes into force on July 1, 2007.

Emma Thorne | alfa
Further information:
http://www.nottingham.ac.uk

More articles from Health and Medicine:

nachricht Cholesterol-lowering drugs may fight infectious disease
22.08.2017 | Duke University

nachricht Once invincible superbug squashed by 'superteam' of antibiotics
22.08.2017 | University at Buffalo

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Cholesterol-lowering drugs may fight infectious disease

22.08.2017 | Health and Medicine

Meter-sized single-crystal graphene growth becomes possible

22.08.2017 | Materials Sciences

Repairing damaged hearts with self-healing heart cells

22.08.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>