Urinary Na/K, low sleep efficiency up risk of home hypertension

Urinary sodium-to-potassium (Na/K) and reduced sleep efficiency are newly identified risk factors for home hypertension and, when taken together, have a greater impact than that of conventional risk factors, a recent study has found.

Researchers cross-sectionally examined 1,384 adults (aged ≥20 years, 991 women) who had completed the follow-up survey of the Tohoku Medical Megabank cohort study. All participants had measurements of home blood pressure, sleep efficiency, and urinary Na/K ratio, as well as counted their steps for at least 7 days. Home hypertension was defined as blood pressure ≥135/85 mmHg at home or treatment for hypertension.

Overall, 39.0 percent (n=540) of the participants had home hypertension. The presence of any conventional risk factor (body mass index ≥25 kg/m² or current moderate-to-heavy daily alcohol consumption) increased the risk of hypertension by nearly three times (odds ratio [OR], 2.80, 95 percent confidence interval [CI], 2.15–3.65; p<0.001).

The novel risk factors tested in this study, urinary Na/K and sleep efficiency, had a similar effect, though to a slightly weaker degree (OR, 2.50, 95 percent CI, 1.93–3.22; p<0.001).

However, calculating for the population attributable fraction (PAF) for either set of risk factors, the researchers found that conventional risk factors accounted for 30.2 percent of all home hypertension cases, as opposed to a PAF of 39.0 percent when looking at the novel risk factors.

“This finding was shown regardless of the age group. The management of the urinary Na/K ratio and sleep efficiency as well as conventional risk factors is desired to prevent hypertension,” the researchers said.