Heart Beat: October 2018
When Depression Strikes After a Heart Attack, Antidepressants May Save Lives
Depression after a heart attack can have serious, even deadly, consequences. However, the effect of antidepressants on outcomes has been unknown. A 300-patient study published in the July 24/31 issue of JAMA suggests that treatment with the selective serotonin reuptake inhibitor (SSRI) escitalopram (Lexapro®) significantly reduced the risk of a major cardiac event. Patients who had recently suffered a major or minor heart attack were randomized to the antidepressant or placebo for 24 weeks and then followed for a median of eight years. All-cause death, deaths from heart disease, heart attacks and revascularizations with angioplasty and stenting were tracked. At the end of the study, 40.9 percent of the patients on escitalopram had met one of these outcomes, compared with 53.6 percent of those who had received the placebo. When individual outcomes were examined, the SSRI beat placebo in all measures. However, only reduction in heart attack (8.7 percent vs 15.2 percent) was statistically significant.
Two Weeks of Inactivity Can Cause a Prediabetic Patient to Develop Diabetes
A study of prediabetic seniors found that as little as two weeks of physical inactivity pushed their blood sugar into the range of diabetes. Moreover, their blood sugar levels did not return to normal after two weeks of regular activity. In this small study, the activity level of 22 overweight adults ages 65 to 73 was monitored for one week. Subsequently, the seniors took fewer than 1,000 steps a day for 14 days before resuming a normal life. As reported in the July 9 issue of The Journals of Gerontology, periodic testing showed their insulin resistance increased and insulin sensitivity decreased when activity levels dropped suddenly and dramatically and failed to normalize after two weeks of “recovery.” This reinforces the need to keep close tabs on elderly patients who are waylaid by illness, hospitalization or bed rest to ensure their blood sugar levels do not spiral out of control.
Cleveland Clinic Researchers Create a New Class of Drugs that Fight Heart Disease in an Entirely Different Way
Five years ago, Cleveland Clinic researchers identified a product in the blood known as trimethylamine N-oxide (TMAO), which is produced when bacteria in the gut digest certain nutrients found in meat, egg yolks and high-fat dairy. They showed that TMAO increases platelet reactivity and blood clotting. High blood levels of TMAO were found to predict future risk of heart attack, stroke and death. The same researchers have now created a new class of drugs that prevent gut bacteria from making TMAO without harming the microbes, which are considered generally beneficial. In the September issue of Nature Medicine, they explain that this class of drugs, which they call “mechanism-based inhibitors,” trick the bacterial cells into thinking they are nutrients and absorbing them. Once inside the cell, the drug inhibits, or blocks, the production of TMAO. When tested in mice, a single dose of the new drug reversed platelet reactivity and excessive clot formation without causing side effects. The drug was effective for three days and simply remained in the gut, where it continued to target its microbe. This new class of drugs has the potential to reduce deaths from cardiovascular disease and will move on to human clinical trials.
Should Very Low LDL Be Pushed Lower? Studies Suggest the Answer Is Yes.
The benefits of low LDL cholesterol have been firmly verified in clinical trials of statins and other lipid-lowering drugs. In these trials, the rates of death from coronary artery disease, heart attack, stroke and revascularization have dropped in parallel with declining LDL levels. For this reason, an LDL level of 70 mg/dL or lower is advised for anyone with cardiovascular disease. Yet just how low an LDL level can go and remain safe and effective has been a matter of discussion and debate. A study published online Aug. 1 in JAMA Cardiology added insight to this issue. When researchers analyzed data from large clinical trials where these drugs were used alone and in combination to achieve LDL levels as low as 21 mg/dL, they found consistent evidence these ultra-low levels produced additional reductions in cardiovascular events without any serious adverse events.