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Women who use antibiotics for two months or more have higher risk of heart attack and stroke

‘Considering the potentially cumulative adverse effects, the shorter time of antibiotic use the better’

Alex Matthews-King

Health Correspondent

Thursday 25 April 2019 06:12 BST

(iodrakon/iStock)

Women who used antibiotics for longer than a two month period saw their risks of suffering a heart attack or stroke rise by a third, a study has found.

Researchers, led by Tulane University in New Orleans, warn that long-term antibiotic use may be increasing risks of cardiovascular disease by wiping out beneficial bacteria that colonise our guts.

The risk was most pronounced in women over 60, who saw rates of arterial and heart diseases rise 32 per cent relative to women who did not take antibiotics during the eight year study period.

"Antibiotic use is the most critical factor in altering the balance of microorganisms in the gut," senior author of the study Professor Lu Qi, director of the university's Obesity Research Centre, and a professor at Harvard said.

"Previous studies have shown a link between alterations in the microbiotic environment of the gut and inflammation and narrowing of the blood vessels, stroke and heart disease."

Under the skin – best of the British Heart Foundation 2018 image prize

Show all 10

1/10Under the skin – best of the British Heart Foundation 2018 image prize

Under the skin – best of the British Heart Foundation 2018 image prize

Subarachnoid vessels

The runner-up image came from Matt MacGregor Sharp, a PhD student at the University of Southampton. The super-high resolution image shows a normal artery at the surface of a rat’s brain and was taken with a powerful scanning electron microscope. These ‘subarachnoid vessels’ supply blood to the brain and also act like a drain to remove toxic waste products. Matt Macgregor’s team are trying to show that failure to remove waste by these vessels is one of the underlying causes of vascular dementia. The researchers took the image using a technique called ‘freeze fracture’, where tissue or cell samples are frozen and then split apart to reveal the hidden layers within the sample so they can be studied in extreme detail. Sitting above the brown brain tissue, the artery appears blue, and its surrounding layer, the pia mater, is shown in purple.

Matt MacGregor Sharp, University of Southampton, British Heart Foundation - Reflections of Research

Under the skin – best of the British Heart Foundation 2018 image prize

Explosive beginnings

Winner: Endothelial cells line all blood vessels in the body, forming a barrier between the circulating blood and the vessel wall. They also help to protect blood vessels from damage and release important chemical messengers which help to control blood pressure. The winning researcher, Courtney Williams, is a Masters student and PhD candidate at Leeds University. Her lab are developing new ways to map the growth of new blood vessels within their surrounding landscape in 3D. Understanding the complex secrets of blood vessel formation could be harnessed to boost the regrowth of damaged blood vessels after a heart attack, and halt blood vessel growth when it’s counterproductive.

Courtney Williams, Leeds University, British Heart Foundation - Reflections of Research

Under the skin – best of the British Heart Foundation 2018 image prize

A snapshot of platelet production - Reflections of Research Supporters’ Favourite

This image from Abdullah Obaid Khan, a PhD student at the University of Birmingham, won the supporters’ favourite. What look like precious jewels are actually platelets forming within the bone marrow. Platelets are the smallest of our circulating blood cells with a hugely important role in preventing bleeding. However, they also play a role in the formation of clots, which can lead to heart attacks and strokes. Abdullah Obaid Khan and his team are studying rare bleeding disorders.

Abdullah Obaid Khan, University of Birmingham, British Heart Foundation - Reflections of Research

Under the skin – best of the British Heart Foundation 2018 image prize

Cardiac collagen web - Shortlist

This colourful image shows the web-like, network of the smallest blood vessels in the heart – the microvessels. Magenta marks the outer collagen layer of the vessels; while orange marks their inner lining and blue the cell nuclei. Dr Neil Dufton, Imperial College London

Dr Neil Dufton, Imperial College London, British Heart Foundation - Reflections of Research

Under the skin – best of the British Heart Foundation 2018 image prize

Heart to Heart - Shortlist

This piece shows four ventricles (from a mouse) arranged into the shape of the hearts four normal chambers. The researchers have used fluorescent markers to recognise certain proteins and created the image using of hundreds of images assembled together. Dr Elisa Avolio and Dr Zexu Dang, University of Bristol

Dr Elisa Avolio and Dr Zexu Dang, University of Bristol, British Heart Foundation - Reflections of Research

Under the skin – best of the British Heart Foundation 2018 image prize

Loving artery - Shortlist

This image shows a cross section of an artery and the different layers which make up the artery wall. Affiliate Professor Silvia Lacchini, University of Glasgow

Silvia Lacchini, University of Glasgow, British Heart Foundation - Reflections of Research

Under the skin – best of the British Heart Foundation 2018 image prize

Oxidative inkblot - Shortlist

This colour explosion shows one of the culprits in cardiovascular disease – an enzyme called NADPH oxidase. The enzyme is considered ‘Janus faced’ because it is important in health, as well as disease. This picture shows the active enzyme in patients who have high blood pressure. Dr Livia de Lucca Camargo, University of Glasgow

Dr Livia de Lucca Camargo, University of Glasgow, British Heart Foundation - Reflections of Research

Under the skin – best of the British Heart Foundation 2018 image prize

Neon skeleton - Shortlist

This image shows the developing blood vessel system of a two day old zebrafish embryo. The researchers used gene enhancers (the on-off switches of genes) to switch on fluorescent markers in different types of endothelial cells – the important cells which line all blood vessels. All blood vessels switch on the red marker, while the veins also switch on the green marker, resulting in yellow veins and red arteries. Dr Svanhild Nornes, University of Oxford

Dr Svanhild Nornes, University of Oxford, British Heart Foundation - Reflections of Research

Under the skin – best of the British Heart Foundation 2018 image prize

Calcium reef - Shortlist

This image shows calcium in blood vessel cells from people who have high blood pressure and resembles Australia’s Great Barrier Reef. Dr Rheure Alves-Lopes, University of Glasgow

Dr Rheure Alves-Lopes, University of Glasgow, British Heart Foundation - Reflections of Research

Under the skin – best of the British Heart Foundation 2018 image prize

Budding blood vessels - Shortlist

This image shows the growing blood vessels in the mouse retina. In red you can see all the blood vessels and in yellow/green you can see the blood vessels that are actively growing (a process called sprouting). PhD candidate Kira Chouliaras, University of Oxford

Kira Chouliaras, University of Oxford, British Heart Foundation - Reflections of Research

The study, published in the European Heart Journal, used participants in a long running US study including 36,500 women were monitored over nearly eight years.

Over this period, 1,056 participants developed cardiovascular disease, but the absolute risk of issues remained low.

Among women 60 plus there were six heart attacks or strokes per 1,000 women, compared to three per thousand in women the same age who didn't take antibiotics. this increase remained pronounced even after controlling for other health risks or factors that might explain the rise.

Women in middle age had a smaller, but still pronounced increased risk of around 28 per cent, but there were no effects found in women aged 39 or younger.

"As these women grew older, they were more likely to need more antibiotics, and sometimes for longer periods of time, which suggests a cumulative effect may be the reason for the stronger link in older age between antibiotic use and cardiovascular disease," said Dr Yoriko Heianza, another of the authors.

Antibiotics alter the balance of the gut ecosystem, destroying beneficial bacteria and increasing the prevalence of viruses, harmful bugs and infectious fungal organisms such as Candida.

Women in the study most commonly took antibiotics for lung infections, urinary tract infections, and dental problems.

Prof Qi added: "Our study suggests that antibiotics should be used only when they are absolutely needed.

"Considering the potentially cumulative adverse effects, the shorter time of antibiotic use the better."

Additional reporting by PA

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