PURPOSE: To evaluate the prevalence of sleep disordered breathing (SDB)in Chinese subjects with difficult-to-control hypertension.
METHODS: Medical records of patients attending the hypertension clinic at a University teaching hospital were screened over one year. Inclusion criteria were age 18 - 65 with hypertension requiring ≥ 3 anti-hypertensive medications. Patients with known secondary causes of hypertension, unstable medical illnesses in the past three months, on drugs other than anti-hypertensives that might influence blood pressure, were excluded. Eligible subjects were invited to undergo 24-hour ambulatory blood pressure measurement and polysomnography(PSG).
RESULTS: 116 subjects were interviewed and 92 consented for PSG. 6 defaulted the PSG appointment. 10 were awaiting their PSG. Among the 76 subjects already completed PSG, the mean age was 52.2 ± 8.4, male:female=1.5:1, mean body mass index 29.6 ± 5.3 kg/m2, mean systolic blood pressure 141.9 ± 17.3mmHg, mean diastolic blood pressure 81.9 ± 10.9mmHg. Sleep disordered breathing (Apnea hypopnea index ≥ 5/hour) was diagnosed in 57 subjects (57/76=75%)(mean age 52.4 ± 9.0, male:female=2.4:1, mean BMI 30.6 ± 4.9 kg/m2). 41 (41/76=53.9%) had moderate or severe SDB (AHI ≥ 15/hour). Among those with SDB, Obstructive apnea was the predominant type of SDB seen. Central apneas predominance was observed in two subjects (2/57=3.5%).
CONCLUSION: Sleep disordered breathing, in particular obstructive sleep apnea, was found to be highly prevalent in Chinese with difficult-to-control hypertension.
CLINICAL IMPLICATIONS: The finding should arouse higher awareness of the common co-existence of sleep disordered breathing in patients with difficult-to-control hypertension.
DISCLOSURE: Macy Lui, No Financial Disclosure Information; No Product/Research Disclosure Information