Millions of Americans take proton pump inhibitors to treat acid reflux and heartburn. Known as PPIs, they are among the most prescribed drugs in the United States and are widely available over the counter. 
 
 But according to preliminary research presented today at an American Heart Association conference in New Orleans, these medications may also increase the risk of ischemic stroke 
 
 Ischemic strokes are the most common type of stroke, according to the Centers for Disease Control and Prevention . They occur when a blood clot cuts off blood flow to the brain. 
 
 "PPIs have been associated with unhealthy vascular function, including heart attacks, kidney disease and dementia," said Dr. Thomas Sehested, the study's lead author and a researcher at the Danish Heart Foundation . "We wanted to see if PPIs also posed a risk for ischemic stroke, especially given their increasing use in the general population." 
 
 Most serious warning yet 
 
 Protonix, The research was conducted in Denmark among a quarter-million patients who suffered from stomach pain and indigestion, and were taking one of four PPIs: Prilosec Prevacid or Nexium 
 
 Overall stroke risk increased 21% among patients who were taking a PPI, according to the study. At the lowest doses, the authors found either no or minimal increased risk of stroke. At the highest doses, they found that stroke risk increased 33% for Prilosec and Prevacid patients, 50% for Nexium patients and 79% for Protonix patients. 
 
 In an email to CNN, P&G, the company that makes Prilosec, said the drug is an "FDA approved, safe and effective remedy to relieve frequent heartburn symptoms. Prilosec OTC has the longest history of safe and effective consumer use of any [over the counter] PPI." 
 
 Takeda, the maker of Prevacid, said it could not comment on the results and conclusions of the study until the full data is published for review. "Patient safety is a top priority ... and we continuously monitor the safety of all our medicines and collaborate with regulatory agencies to ensure this information is reflected in the respective prescribing information," a spokesman said in an email to CNN. 
 
 AstraZeneca, the maker of Nexium, said, "Patient safety is an important priority ... and we believe all of our PPI medicines are generally safe and effective when used in accordance with the label." A spokeswoman said the company was not consulted during the research, so it could not comment on the data. 
 
 Pfizer, the maker of Protonix, did not respond to CNN's request for comment. 
 
 "At one time, PPIs were thought to be safe, without major side effects," Sehested said. "This study further questions the cardiovascular safety of these drugs." 
 
 JUST WATCHED Drug-resistant bacteria found in U.S. Replay More Videos ... MUST WATCH Drug-resistant bacteria found in U.S. 02:18 
 
 A pair of 2010 studies found that PPIs were associated with an increased risk of a serious bacterial infection . Stomach acid seems to play a role in killing off both good and bad bacteria in our gut. When someone is taking PPIs, their amount of stomach acid is reduced, and it creates an environment in which bacteria can flourish. 
 
 "As a culture, we tend to want a pill to deal with our problems, when a lot of people could reduce their heartburn by eating smaller meals, drinking less alcohol or not smoking," Dr. Michael Katz, who wrote an editorial accompanying the studies, told CNN in 2010 
 
 In April, another study published in the Journal of the American Society of Nephrology found that patients who took PPIs had a 96% increased risk of kidney failure and a 28% increased risk of kidney disease, compared with those who were prescribed alternative medications. 
 
 What are the alternatives? 
 
 Medical professionals estimate that the majority of people who suffer from acid reflux or heartburn could drastically or completely reduce their discomfort by making a few lifestyle changes: quit smoking, lose weight and cut back on spicy and fatty foods. 
 
 If your doctor determines that you do need pills for your problem, pharmacist NaaDede Badger-Plange suggests starting with an antacid , such as Tums, Rolaids or Maalox. 
 
 JUST WATCHED Ways to treat heartburn Replay More Videos ... MUST WATCH Ways to treat heartburn 02:40 
 
 "Antacids usually would help if you have less than one incident a week," Badger-Plange said . "So, if you have heartburn very rarely -- especially people who have heartburn associated with certain foods -- they could take antacids." 
 
 Antacids provide quick relief, but only for a short amount of time, said Badger-Plange, and consumers should pay close attention to the ingredients on the label. If you're pregnant, you should avoid sodium bicarbonate and magnesium trisilicate. Patients with kidney disease should avoid antacids that contain aluminum. 
 
 For longer-lasting relief, H2 antagonist medications (also called H2 blockers) are also an option, but they can take a few hours to kick in. 
 
 Join the conversation See the latest news and share your comments with CNN Health on Facebook and Twitter. 
 
 "One thing to keep in mind is, certain products that are in the H2 receptor antagonist class have drug interactions," Badger-Plange said. "So, if you have a lot of medications, you probably want to check with your pharmacist at the counter to make sure it's OK to take those medications." 
 
 As always, you should talk to your doctor before starting or stopping any medication -- prescribed or over the counter. 
 
 For years, Katz has been worried that PPIs "reinforce the idea that the solution to behavioral health issues is to take a pill, and that's just not how we're going to get healthier," he said in 2010. "Consumers need to ask their doctors, 'Why am I taking this? Do I still need this? Do I have an alternative?' " ||||| A popular class of heartburn medications might raise a senior's risk of dementia, a new study suggests. 
 
 Called proton pump inhibitors (PPIs), this group of drugs includes Prilosec, Nexium and Prevacid. They work by lowering the amount of acid produced by the stomach. 
 
 But German researchers found that people 75 or older who regularly take the medications had a 44 percent increased risk of dementia, compared with seniors not using the drugs. The study only found an association, however, and not a cause-and-effect link. 
 
 "To evaluate cause-and-effect relationships between long-term PPI use and possible effects on cognition in the elderly, randomized, prospective clinical trials are needed," said corresponding author Britta Haenisch, from the German Center for Neurodegenerative Diseases in Bonn. 
 
 In the meantime, "Clinicians should follow guidelines for PPI prescription, to avoid overprescribing PPIs and inappropriate use," Haenisch said. 
 
 The report was published Feb. 15 in the journal JAMA Neurology. 
 
 The results are surprising enough that at least one leading expert on aging, Dr. Malaz Boustani, plans to share the findings with older patients who are using PPIs. 
 
 Boustani said earlier studies have linked another type of antacid, H2 blockers, with an increased risk of dementia. Up to now, he's recommended that patients use PPIs to treat acid reflux and steer clear of H2 blockers like Tagamet, Pepcid and Zantac. 
 
 "I'm going to disclose the finding to my patients and then let them decide whether they will take the risk or not," said Boustani, a professor of medicine with the Indiana University Center for Aging Research and a spokesman for the American Federation for Aging Research. "On Monday I have clinic, and if I have patients taking a PPI or an H2 blocker I will tell them exactly what I'm telling you, and then they can decide." 
 
 More than 15 million Americans used prescription PPIs in 2013, at a total cost of more than $10 billion, according to a report by the IMS Institute for Healthcare Informatics. Several popular PPIs -- Prilosec, Prevacid and Zegerid -- also are available over-the counter, further boosting their use. 
 
 Concern has been increasing that Americans might be overusing PPIs to treat minor cases of heartburn or acid reflux. 
 
 As many as 70 percent of PPI prescriptions in the United States have been inappropriately handed out by doctors, and 25 percent of long-term users could stop taking the medication without suffering increased heartburn or acid reflux, according to a study published in January in the journal JAMA Internal Medicine. 
 
 Overuse of PPIs could have drastic effects on health, that study found. For example, the medications have been linked to a 20 percent to 50 percent higher risk of chronic kidney disease. 
 
 And now the German researchers report there also is some evidence that PPI use might affect a person's ability to reason. 
 
 PPIs appear to effect levels of amyloid beta and tau, which are proteins associated with Alzheimer's disease, the German authors said. PPI use can also lead to vitamin B12 deficiency, which has been associated with cognitive decline. 
 
 To test the possible association between PPIs and dementia, the German researchers collected data from a large German health insurance firm on almost 74,000 seniors aged 75 or older. The data ran from 2004 to 2011, and included diagnoses and drug prescriptions. 
 
 About 2,950 patients regularly used PPIs, which for this study was defined as at least one PPI prescription in each quarter of an 18-month interval. 
 
 Regular users of PPIs had a 44 percent increased risk of dementia compared with those not receiving PPI medications. 
 
 However, the study doesn't make clear whether PPIs are also available over the counter in Germany, as they are in the United States, said Dr. Arun Swaminath, director of the inflammatory bowel disease program at Lenox Hill Hospital in New York City. 
 
 If over-the-counter PPIs are available, then more people might have been taking them and the dementia risk described in this paper could be overestimated, Swaminath said. 
 
 "However, I think the point here is that for some patients, weaning off PPIs is reasonable and they should make this decision with their doctors," he said. 
 
 People who want to ease off PPIs can take a number of steps to reduce excess acid or prevent acid reflux, Boustani said. They can eat smaller meals, lay off chocolate and caffeine, and stay upright for a few hours following each meal. 
 
 Boustani added that his group has received federal funding to design clinical trials in which people would be weaned off PPIs, to see how it affects their ability to remember and think. 
 
 Dr. Gisele Wolf-Klein, director of geriatric education at North Shore-LIJ Health System in New Hyde Park, N.Y., added that even the researchers aren't sure why PPIs would affect the aging brain. 
 
 "We don't know what is causing the brain to deteriorate. Until we know this, there's no reason for people who are taking PPIs to be too concerned about that and stop taking those agents if they are needed," Wolf-Klein said. 
 
 Another expert agreed. 
 
 While the study is intriguing, it's not enough for doctors to warn patients off PPI use, said Keith Fargo, director of scientific programs and outreach for the Alzheimer's Association. 
 
 "It does not tell us anything that should change medical practice right now," Fargo said. "I don't think there's going to be an uprising among doctors telling patients not to take their PPIs. This doesn't rise anywhere near the level of evidence you would need for that." 
 
 One of the paper's main flaws is that researchers could not control for diet and body weight as risk factors, Fargo said. 
 
 "Both of those things, we know, are risk factors for developing cognitive decline and dementia in later life, and both of those are reasons why a person might need to take a proton pump inhibitor," Fargo explained. ||||| Popular Heartburn Pills Can Be Hard To Stop, And May Be Risky 
 
 Enlarge this image Katherine Streeter for NPR Katherine Streeter for NPR 
 
 When Marcella Lafayette started having really bad heartburn, she went to her doctor to see if there was anything that might help. 
 
 "I was experiencing a lot of chest pain, back pain caused from heartburn," says Lafayette, 62, of Portland, Ore. 
 
 Her doctor diagnosed her with gastroesophageal reflux disease, or GERD, and prescribed a drug called a proton pump inhibitor, or PPI. The drug worked, but Lafayette soon started having other problems, such as muscle weakness and severe leg cramping. 
 
 Lafayette discovered she was suffering from a magnesium deficiency, a side effect of the drug. She also learned that PPIs can cause not just deficiencies of nutrients but other side effects, such as an increased risk for infections. 
 
 So Lafayette decided to try to stop using her PPI. But whenever she did, her heartburn returned. And the symptoms were much worse. 
 
 "I can't seem to get off the drug, because when I do, I experience severe stomach pain. I can't eat anything without experiencing stomach pain," Lafayette says. "It just feels like you've got a knife in your gut. It's just really painful." 
 
 Lafayette is not alone. Many people have trouble discontinuing PPIs because the amount of acid in their digestive system surges when they stop taking the drug. 
 
 Experiences like Lafayette's, and rising evidence that the drugs may be associated with a variety of increased risks, are making doctors increasingly worried about their wide use. 
 
 "The teaching for many years was that these drugs were quite safe," says John Clarke, a gastroenterologist at Johns Hopkins Hospital in Baltimore. "But there is data that's emerging that suggests PPIs may not be as safe as we think they are." 
 
 An estimated 15 million Americans use PPIs, which are sold by prescription and over the counter under a variety of brand names, including Nexium, Prilosec and Prevacid. 
 
 They work by blocking production of stomach acid. And that could be the root of the problem, according to Clarke. Stomach acid helps digest food and also has a "barrier function against different pathogens which are ingested," he says. 
 
 So when there's less stomach acid, it leaves people vulnerable to nutritional deficiencies and infections, including food poisoning like salmonella, a serious, sometimes life-threatening digestive system infection called Clostridium difficile, and perhaps pneumonia. 
 
 Stomach acid also helps digest food. So if you don't have any of that acid, it can make it hard to get the vitamins, minerals and other nutrients you need from your food — including nutrients that keep bones strong and prevent fractures. 
 
 In addition, one recent study suggested people who take PPIs may be at greater risk of heart disease; another suggested the drugs could increase the risk for chronic kidney disease. 
 
 Updated Feb. 15, 11 a.m. ET: The latest concern is that PPIs might increase the risk for dementia. Britta Haenisch and colleagues at the German Center for Neurodegenerative Diseases in Bonn studied 73,679 people ages 75 and older. The researchers found regular PPI users had at least a 44 percent increased risk of dementia compared with those not using the drugs. 
 
 The researchers caution that the risk could only be considered an "association," until more research could be conducted to produce more conclusive evidence. But the findings indicate "the avoidance of PPI medication may contribute to the prevention of dementia." 
 
 How PPIs might increase the risk for dementia is unclear. But other researchers recently reported that, in the brains of mice, PPIs seem to increase levels of a damaging protein that accumulates in the brains of dementia patients, known as beta-amyloid. 
 
 In an editorial accompanying the study in the journal JAMA Neurology, Lewis Kuller of the University of Pittsburgh wrote that the findings "provided an important and interesting challenge to evaluate the possible association," which is a "very important issue given" how commonly the drugs are used by the elderly, who are already at increased risk for dementia. 
 
 Our original post continues: As this evidence has emerged, Clarke says, "I think it's imperative that people who take these drugs really make sure that they are looking at the risks versus benefit and people don't use these drugs lightly." 
 
 Many people take PPIs when they don't really need them, Clarke says. They could get rid of their heartburn by making lifestyle changes, such as losing weight and cutting back on alcohol, caffeine and spicy and fatty foods. And many people stay on them a lot longer than they need them, he says. PPIs are usually supposed to be taken for two to eight weeks, although doctors may recommend more. 
 
 The companies that make PPIs say they're safe for most people if they use them the way they're supposed to. And doctors say many people really need to take a PPI for severe heartburn. 
 
 "Proton pump inhibitors do have some very positive benefits to patients," says Kenneth DeVault, a gastroenterologist at the Mayo Clinic who is president of the American College of Gastroenterology. "They relieve symptoms better than any other medication that has ever been developed." 
 
 The most important "positive effect of proton pump inhibitors is restoration of a quality of life," DeVault says. "This is probably the big one." 
 
 PPIs may also reduce the risk for esophageal cancer for some people, he says. 
 
 DeVault says if someone really needs a PPI, they should take one. But they should try everything else first, keep an eye out for any side effects, and talk to their doctor about how long they should stay on it.
– Heartburn is a big problem in the US. In fact, proton pump inhibitors (PPIs), which are used to treat acid reflux and heartburn, are among the most prescribed drugs in the country, with millions taking them, and they're becoming more widely available over-the-counter, reports CNN. But a preliminary report just released by the American Heart Association is concerned that the drug—already associated with a higher risk of heart attack and other vascular problems, as the AHA reported earlier this year—may also increase one's risk of ischemic stroke, the most common type caused when a clot cuts off blood flow to the brain. "At one time, PPIs were thought to be safe, without major side effects," the study's lead author says. “This study further questions the cardiovascular safety of these drugs." Researchers followed nearly a quarter-million patients in Denmark who were suffering from stomach pain and indigestion and had an endoscopy. Their average age was 57, and six years later those taking one of four PPIs (Prilosec, Protonix, Prevacid, or Nexium) had a 21% higher risk of stroke than those not taking one. Lowest-dose PPIs didn't increase the risk much if at all, while highest-dose increased it, from 30% for Prevacid to 94% for Protonix. Another type of acid-lowering meds called H2 blockers (think Pepcid and Zantac) showed no elevated risk. "As a culture, we tend to want a pill to deal with our problems, when a lot of people could reduce their heartburn by eating smaller meals, drinking less alcohol, or not smoking," one doc told CNN in 2010. (PPIs are also associated with a higher risk of dementia.)