Heartfelt with Dr Melissa Walton-ShirleyView all posts »
Quinine increases CHF mortality? Watch that gin and tonic!Aug 25, 2012 06:36 EDT
My relationship with quinine as a medicinal has been at most marginal throughout my career in private practice. I've prescribed it in the distant past as an off-label therapy for leg cramps, recalling well my fear that a "quinine" prescription might be mistaken for quinidine, the antiarrhythmic black sheep of cardiac meds long relegated to that dark dungeon of proarrhythmia. Today's presentation by Dr Charlotte Andersson from Gentofte Hospital in Denmark cited a concerning "number needed to harm" of only 38 patients when quinine was in the pharmacologic mix of ischemic heart failure patients treated with beta blockers. Considering how pervasive quinine use is in the European population and as an over-the-counter offering in the US, it's a topic worthy of examination. My patients still request it from time to time but the FDA's warnings in 2006 and 2011 gave me pause and I've not recommended it for several years.
The Jesuit priests brought this compound produced from the bark of the cinchona tree from Peru and Bolivia into Europe, where it found its way into the earliest of antimalarial therapies. The indigenous population in those countries had no other therapies that could produce enough muscle relaxation to decrease shivering from high fever. Imagine life with no pharmacy available to pick up a bottle of acetaminophen or naproxen. Quinine's analgesic, antipyretic, and anti-inflammatory properties are still widely recognized. Evidence of the impact of this powerful discovery is still seen in the number of Europeans who reside in West Africa to this day. The mix of quinine with sweetened water produced the first tonic water, and now small amounts of it are consumed in a favorite drink known as gin and tonic.
The study population in today's presentation included 136 427 patients with a mean age of 74 years, 47% female, with a 2.5-year follow-up. They mined the national patient register, the Danish prescription register, and the population register to find patients treated with loop diuretics. The patients included were patients hospitalized for the first time with a diagnosis of heart failure and were followed for risk of death for 2.8 years. Of the patients, 11% had used quinine during that follow-up period. The adjusted relative risk for quinine use was 1.03. It was both interesting and disappointing that only 60% of ischemic heart failure patients received beta blockers. Comments from the moderators postulated a link between bradycardia and possible prolongation of the QT interval, although this was only speculation. The shortcomings of this study included the inability to track the exact dose of quinine, the duration of exposure to quinine, and the impact of those issues on mortality.
The final slide of today's presentation depicted a young woman from the 50s holding up a drink glass with ice cubes and a lime slice. She's smiling through ruby red lips with side-swept hair cut short in a bob, a double strand of pearls draped about her neck. The depiction below the visual stated "I'm on the gin-and-tonic diet! So far, I've lost two days!"
Hope someone tells her about this presentation. If she's on beta blockers for ischemic heart disease, she just might lose more.