Risk of resistant hypertension associated with insomnia in patients with obstructive sleep apnea

Patients with obstructive sleep apnea (OSA) have a high prevalence of hypertension but vary in blood pressure (BP) control, which may be partially explained by comorbid insomnia. We investigated the association of insomnia symptoms with uncontrolled BP and resistant hypertension (RH) in OSA patients.

Between 2018 and 2021, hypertensive patients with OSA were enrolled. Information on demographic characteristics, insomnia symptoms, class of antihypertensive medications, BP control and sleep study data were collected. Controlled BP was defined as systolic BP < 140 mm Hg and diastolic BP < 90 mm Hg (BP standard); uncontrolled BP as above BP standard with use of 1-2 classes of antihypertensive medication; and RH as above BP standard with the use of ≥3 classes of antihypertensive medication (including a diuretic). Multinomial logistic regression models were fit to determine the association between insomnia symptoms and uncontrolled BP or RH (versus controlled BP) after multivariable adjustment.

Among the analytic sample (n = 326), 64.1% of participants had uncontrolled BP and 15.6% had RH. OSA severity was associated with a higher odds of RH (OR, 2.92; 95% CI, 1.71-4.99). After adjustment for confounders including demographic characteristics, sedative hypnotics usage, sleepiness, OSA severity and quality of life, participants experiencing insomnia symptoms had a 3.0 times higher odds of RH. Insomnia was not associated with uncontrolled BP.

Experiencing insomnia was associated with increased odds of RH in OSA patients. These results suggest that comorbid insomnia may contribute to inadequate BP control in OSA patients.