Atrial fibrillation (AF) is more likely to occur among middle-aged men with a diastolic blood pressure of just 80 mm Hg or higher, a new study suggests.
Researchers found that the risk of developing the disorder in later life increased among men whose blood pressure readings were at the upper end of normal.
The 35-year study involved 2,014 men in Norway aged 40-59. The participants had their blood pressure recorded at the start of the study, and researchers then conducted a number of follow-up surveys.
A second study was completed after an average of seven years, in which 1,758 men took part. Only those who were considered healthy were included in the analysis beyond this point, which reduced the number to 1,423.
A total of 270 men, or 13%, developed AF during this follow-up period. The researchers found that men with systolic blood pressure of 140 mm Hg or higher at the start of the study had a 60% increased risk of developing AF, compared to those with normal systolic blood pressure.
Participants whose blood pressure was classed as upper normal - 128 to 138 mm Hg - had a 50% higher chance of developing AF than those with systolic pressure below 128 mm Hg.
But the researchers also found that men with a diastolic blood pressure of just 80 mm Hg or higher had a 79% increased risk of developing AF compared with those whose reading was below this level.
While hypertension is a known risk factor for AF, the health consequences of upper-normal blood pressure are not yet fully understood.
The researchers said: “Our results indicate that men with upper-normal blood pressure appear to have a higher risk for AF than men with lower blood pressure.”
The findings have been published in Hypertension, the journal of the American Heart Association.