A recent trial has found a J-shaped relationship between coffee consumption and heart failure suggesting that low levels of coffee consumption may actually be protective and reduce the risk of heart failure.

The researchers carried out a meta-analysis of five trials, four of which were conducted in Sweden and the fifth in Finland. It was a dose-response analysis of prospective studies that assessed the relationship between habitual coffee consumption and the risk of heart failure.

The five studies included 140,220 patients and 6,522 heart failure events. The study population consisted primarily of people without a history of cardiovascular disease or hypertension. The individual studies adjusted for demographics and standard cardiovascular risk factors such as cholesterol levels.

There was a statistically significant J-shaped relationship between coffee intake and heart failure.

Compared with no consumption, the strongest benefit was seen with four cups per day, relative risk (RR) 0.89 (95% CI: 0.81-0.99) and a potentially higher risk seen at greater levels of consumption, RR with 10 cups or more 1.01 (95% CI: 0.90-1.14).

There was no evidence that the relationship between coffee consumption and heart failure risk varied by gender or baseline history of myocardial infarction or diabetes.

The management of heart failure often centres around pharmacotherapy and more specialised interventions such as cardiac resynchronisation therapy. It can be easy to forget that lifestyle interventions can be just as important both in the management and prevention of heart failure as they are in other conditions such as coronary heart disease and diabetes.

The issue of caffeine intake and in particular coffee consumption remains a subject of debate.

The underlying mechanism is unclear but the results were convincing enough to lead the authors to conclude that current heart failure prevention guidelines based on the view that coffee raises risk should be reconsidered.

Dr Peter Savill