stroke

study-finds-link-between-marijuana-use-and-cardiovascular-disease

Study finds link between marijuana use and cardiovascular disease

cannibis, cardiovascular disease, health, heart attack, marijuana, Science, stroke / /

Association —

Researchers call for more studies to understand why they’re linked.

–

A cannabis flower is seen at East End Flower Farm, in Mattituck, New York, on November 16, 2023.

Enlarge / A cannabis flower is seen at East End Flower Farm, in Mattituck, New York, on November 16, 2023.

Survey data collected from more than 430,000 US adults over multiple years suggests a strong, statistically significant link between the use of cannabis and an increased risk of cardiovascular disease, specifically heart attack and stroke.

The open-access study, published this week in Journal of the American Heart Association, found that people who used cannabis every day had 25 percent higher odds of having a heart attack and 42 percent higher odds of having a stroke compared with those who did not use cannabis at all.

But, the national survey data—collected between 2016 and 2020—also contained data on people who used cannabis less frequently than daily. Survey respondents were asked how many days in the past 30 days they used cannabis, which allowed researchers to estimate the odds of cardiovascular disease along the whole spectrum of cannabis use. And they found near-linear dose-responses, with more days of use per month associated with higher risk.

This isn’t the first time that researchers have found an association between cannabis use and cardiovascular disease, but the study is among the largest to date—with a sample size between three and 17 times larger than previous studies. Its size not only added weight to the link but also allowed the researchers to drill down into other risk factors for cardiovascular disease.

Clear link

One common complicating factor is that people who use cannabis also often use tobacco products, which carry their own increased risk for cardiovascular disease. In the new study, led by Abra Jeffers of Massachusetts General Hospital, researchers were able to do two additional analyses: one that looked at cardiovascular disease risk in people who use cannabis but had never used tobacco products and a second one that looked at people who used cannabis but had never used tobacco products or e-cigarettes. Without tobacco use, the higher odds of heart attack and stroke persisted for people who used cannabis. For those without tobacco or e-cigarette use, only the higher odds of stroke remained.

The researchers also looked at age, another complicating factor. Heart disease can take years or decades to develop, but people who use cannabis tend to skew younger. The 434,104 people who took the survey ranged from age 18 to 74, and the analyses adjusted for other health factors, including alcohol use, diabetes, body mass index, and physical activity. When the researchers looked at just the adults who would be considered on the young side for developing cardiovascular disease (less than 55 for men and less than 65 for women), they found that cannabis use also increased the odds of premature cardiovascular disease—and again the link was independent of tobacco and e-cigarette use.

In all, the researchers concluded that “these data suggest that cannabis use may be a risk factor for cardiovascular disease and may be a risk factor for premature cardiovascular disease,” they wrote. This is particularly concerning, they add, because of the growing acceptance and use of cannabis in the US and a decline in perceived health risks.

Limitations

But, the study has limitations that preclude a firm conclusion that cannabis is causing cardiovascular disease. The study relies on self-reported data on both cardiovascular health and cannabis use—both of which can be unreliable. It also relied on data collected at a specific point in time. It’s possible that some people turned to cannabis use after developing cardiovascular disease rather than before, for instance. The survey data can’t make that distinction; it’s only making an association. The authors note that cardiovascular disease, heart attack, and stroke have not previously been identified as major reasons that people use cannabis. This lessens the reverse concern that cardiovascular disease is increasing the odds of cannabis use. But, the researchers do note that many studies have linked the use of cannabis to chronic pain, insomnia, and anxiety—all of which have also been associated with cardiovascular disease. Last, the survey data does not include data on people’s actual cardiovascular health, such as blood pressure and lipid profiles.

Another wrinkle to the study is the route of cannabis use and how it may play a role in the link to cardiovascular disease. About 74 percent of cannabis users in the study reported smoking cannabis, which could potentially increase the risk of cardiovascular disease much the same way tobacco cigarettes do—a result of inhaling particulate matter into the lungs. It’s unclear if edible cannabis products would weaken the association seen in the study.

But, the authors note that there is a biologically plausible link between cannabis and cardiovascular disease. Cell signaling receptors that detect components of cannabis (endocannabinoid receptors) are ubiquitous throughout the cardiovascular system, the researchers note. And the key psychoactive substance in cannabis, Tetrahydrocannabinol (THC), can increase blood pressure and heart rate during use.

Study finds link between marijuana use and cardiovascular disease Read More »

surprising-link-found-between-niacin-and-risk-of-heart-attack-and-stroke

Surprising link found between niacin and risk of heart attack and stroke

cardiovascular disease, cleveland clinic, Genetics, health, heart attack, inflammation, metabolites, niacin, Science, stroke, vitamin b3 / /

Unexpected —

Breakdown products of niacin, aka Vitamin B3, may spur vascular inflammation.

–

A shopper looks at a meat display on June 20, 2022, at the Market 32 Supermarket in South Burlington, Vermont. Niacin can be found in foods such as red meat, poultry, fish, fortified cereals and breads, brown rice, nuts, legumes, and bananas.

Enlarge / A shopper looks at a meat display on June 20, 2022, at the Market 32 Supermarket in South Burlington, Vermont. Niacin can be found in foods such as red meat, poultry, fish, fortified cereals and breads, brown rice, nuts, legumes, and bananas.

In the early 20th century, the deadliest nutrient-related disease in US history ravaged the American South. Pellagra, a disease caused by a deficiency in niacin and/or tryptophan, is marked by the four “D’s”: diarrhea, dermatitis that leads to gruesome skin plaques, dementia, and death. At its peak during the Great Depression, pellagra killed nearly 7,000 Southerners a year. Between 1906 and 1940, researchers estimate that the epidemic struck roughly 3 million Americans, killing around 100,000.

The deadly epidemic led to voluntary—and eventually mandatory—fortification of wheat and other cereals with niacin (aka Vitamin B3). By the middle of the century, pellagra nearly vanished from the US. But, decades later, the public health triumph may be backfiring. With Americans’ diets more reliant than ever on processed, niacin-fortified foods, the average niacin intake in the US is now nearing what’s considered the tolerable upper limit of the nutrient, according to a federal health survey. And an extensive study recently published in Nature Medicine suggests that those excess amounts of niacin may be exacerbating cardiovascular disease, increasing risks of heart attacks, strokes, and death.

The study, led by Stanley Hazen, chair of Cardiovascular and Metabolic Sciences at Cleveland Clinic’s Lerner Research Institute, connected high blood levels of a breakdown product of niacin—and to a lesser extent, tryptophan—to an elevated risk of major adverse cardiovascular events (MACE). And this elevated risk appears to be independent of known risk factors for those events, such as high cholesterol.

“What’s exciting about these results is that this pathway appears to be a previously unrecognized yet significant contributor to the development of cardiovascular disease,” Hazen said in an announcement of the study. It can be measured, he added, and one day could be a new avenue for treatment and prevention.

Metabolite fishing

Hazen and his colleagues didn’t start out suspecting niacin could be a culprit in cardiovascular disease. They arrived at that point after fishing through patients’ blood plasma. The researchers were carefully inventorying metabolites in the fasting plasma of 1,162 patients who had been evaluated for cardiovascular disease. They were looking for anything that might be linked to a heightened risk of heart attack, stroke, or death in a three-year period that couldn’t entirely be explained by other risk factors. Despite advances in identifying and treating cardiovascular disease, researchers have noted that some patients continue to be at risk of serious cardiovascular events despite having their traditional risk factors treated and controlled. Hazen and his colleagues wanted to know why.

The metabolomic trawling came up with an unknown metabolite (signature C7H9O2N2) that was significantly linked to having a MACE in the three-year period. People who had higher levels of this metabolite circulating in their systems were within the top 75th percentile for relative MACE risk in the cohort. Further work identified the metabolite as actually being two related molecules: 2PY (N1-methyl-2-pyridone-5-carboxamide) and 4PY (N1-methyl-4-pyridone -3-carboxamide)—both the final breakdown products of niacin.

Surprising link found between niacin and risk of heart attack and stroke Read More »

covid-shots-protect-against-covid-related-strokes,-heart-attacks,-study-finds

COVID shots protect against COVID-related strokes, heart attacks, study finds

65+, adults, blood clot, CDC, COVID-19, fda, health, heart attack, Science, stroke, vaccine / /

stay up to date —

Data provides more evidence older people should stay up to date on COVID vaccines.

–

A vial of the updated 2023-2024 formula of Pfizer's COVID-19 vaccine at a CVS Pharmacy in Eagle Rock, California, on September 14, 2023.

Enlarge / A vial of the updated 2023-2024 formula of Pfizer’s COVID-19 vaccine at a CVS Pharmacy in Eagle Rock, California, on September 14, 2023.

Staying up to date on COVID-19 vaccines can cut the risk of COVID-related strokes, blood clots, and heart attacks by around 50 percent in people ages 65 years or older and in those with a condition that makes them more vulnerable to those events, according to a new study from the Centers for Disease Control and Prevention.

The finding, published this week in the CDC’s Morbidity and Mortality Weekly Report, should help ease concerns that the shots may conversely increase the risk of those events—collectively called thromboembolic events. In January 2023, the CDC and the Food and Drug Administration jointly reported a preliminary safety signal from their vaccine-monitoring systems that indicated mRNA COVID-19 vaccines may increase the risk of strokes in the 21 days after vaccination of people ages 65 and older. Since that initial report, that signal decreased, becoming statistically insignificant. Other vaccine monitoring systems, including international systems, have not picked up such a signal. Further studies (summarized here) have not produced clear or consistent data pointing to a link to strokes.

In May, the FDA concluded that the evidence does not support any safety concern and reported that “scientists believe factors other than vaccination might have contributed to the initial finding.”

But, the statistical blip could potentially cause lingering concerns. While clinicians had noted lower rates of thromboembolic events among vaccinated people, the authors of the new study noted that, until now, there were no rigorous estimates of how effective COVID-19 vaccines are at preventing those events.

For their analysis, they primarily looked at two groups of patients: A group of 12.7 million Medicare beneficiaries ages 65 and older and a group of around 78,600 Medicare beneficiaries ages 18 and older with end-stage renal disease (ESRD) on dialysis, a condition that increases their risk for thromboembolic events, including COVID-19-related thromboembolic events. Using medical claims records from September 2022 to March 2023, the researchers compared rates of thromboembolic events among the people in those groups that had gotten a bivalent COVID-19 booster dose and those who had only gotten the original monovalent COVID-19 vaccine in the past. To be considered a COVID-related thromboembolic event, the event had to occur within a week of or a month after a COVID-19 diagnosis.

Protective effect

In the group of 12.7 million patients ages 65 and older, about 5.7 million (45 percent) had gotten the bivalent booster, making them up to date on their COVID-19 vaccinations at the time. The remaining 7 million (55 percent) had only gotten the original vaccine.

During the study period, 17,746 patients who were not up to date on their COVID shots got COVID-19 and experienced a COVID-related thromboembolic event. Of the bivalent boosted patients, there were 4,255 COVID-related thromboembolic events. The researchers adjusted for confounding factors, such as age, race, and time of vaccination, and estimated that the bivalent booster was overall 47 percent effective at preventing COVID-related thromboembolic events, which again include strokes, blood clots, and heart attacks.

A sub-analysis including the time since vaccination indicated that the estimated effectiveness waned about two months after receipt of the vaccine, dropping early effectiveness of 54 percent down to 42 percent at 60 days or more.

Among the 78,600 patients ages 18 and up with ESRD, 23,229 (29.5 percent) received a bivalent dose and thus were up to date on their COVID-19 vaccines. The remaining patients (70.5 percent) had only received an original vaccine, and of those, 917 experienced a COVID-19-related thromboembolic event after getting the pandemic virus. Among the up-to-date patients, there were only 123 events. After adjustments, the researchers estimated that the vaccines’ effectiveness against thromboembolic events was 51 percent in this group, which also waned slightly over time.

The study has limitations, such as that it can’t account for previous COVID-19 infections, which could alter people’s risk of developing complications from COVID-19, including thromboembolic events. It relied on medical claims, which have limitations, and it’s possible there are other confounding factors, such as the use of Paxlovid and behavioral differences. Last, Medicare beneficiaries are not representative of the whole population.

But, given the data available, the study authors concluded that it appears the bivalent vaccine dose “helped provide protection against COVID-19–related thromboembolic events compared with more distant receipt of original monovalent doses alone.” The authors recommend that, “to prevent COVID-19–related complications, including thromboembolic events, adults should stay up to date with recommended COVID-19 vaccination.”

The CDC currently estimates that only 21 percent of adults ages 18 and up have received the latest COVID-19 booster dose, including 41.5 percent of adults ages 65 and up.

COVID shots protect against COVID-related strokes, heart attacks, study finds Read More »