Elevated SBP level tied to increased dementia risk in middle-aged patients with AF

Systolic blood pressure (SBP) above 129 mm Hg was associated with an increased risk of dementia in middle-aged patients with atrial fibrillation (AF), according to a study presented at EHRA 2019.

Researchers gathered data from the Korean National Health Insurance Service database and evaluated 196,388 patients with AF and hypertension who underwent treatment between 2005 and 2016. SBP levels were measured in all participants aged 50–59 (n=40,569), 60–69 (n=72,730), 70–79 (n=67,514), and ≥80 years (n=15,575). [EHRA 2019, abstract 864]

Compared with middle-aged (50–59 years) individuals with an SBP level of 120–129 mm Hg, those with higher SBP levels had a greater risk of dementia (adjusted hazard ratio [adjHR], 1.06, 95 percent confidence interval [CI], 1.01─1.10 for SBP 130–139 mm Hg and adjHR, 1.15, 95 percent CI, 1.04─1.27 for SBP ≥140 mm Hg).

Similar findings were observed in the group comprising individuals aged 60–69 years, with those with higher SBP levels having a greater risk of dementia than those with SBP levels of 120–129 mm Hg (adjHR, 1.01, 95 percent CI, 0.96─1.06 for SBP 130–139 mm Hg and adjHR, 1.07, 95 percent CI, 1.01─1.13 for SBP ≥140 mm Hg).

In contrast, elevated SBP levels appeared to have no influence on the risk of dementia among patients aged >70 years.

In a subgroup analysis, patients aged 50–59 years whose SBP dropped from a baseline level of ≥140 mm Hg to 120–129 mm Hg on follow-up had a significantly lower risk of dementia (adjHR, 0.85, 95 percent CI, 0.74─0.98; p=0.02).

“[While] there is no certain way to protect against AF-associated dementia … [our findings show that an SBP level of 120–129 mm Hg may] help midlife patients minimize their risk by as much as 15 percent,” said study lead author Dr Daehoon Kim from Yonsei University College of Medicine in Seoul, Korea.

“[These findings suggest that] strict BP control in midlife can help to prevent AF-associated dementia,” said Kim. However, BP control might be of little help in preventing dementia among individuals older than 70 years, he added.

“[P]roper anticoagulation and early cardiovascular risk factor modification, including … BP [control] and prevention of hypoglycaemia in diabetes patients, likely play an important role in reducing the risk of AF-associated dementia,” Kim noted.