What is the clinical evidence from this study?

Study design: Cross-Sectional. Population: Stage 1 hypertension (n=75). Intervention: Poor sleep quality (PSQI total score > 5) vs. Good sleep quality. Primary outcome: Non-dipping hypertension status (OR 2.955, 95% CI 1.127-7.747).

January 1, 2007Open Access

Sleep quality among relatively younger patients with initial diagnosis of hypertension: Dippers versus non‐dippers

Key Result

Being a poor sleeper (PSQI score > 5) was associated with a 2.955-fold increased risk of having non-dipping hypertension (OR 2.955; 95% CI 1.127-7.747).

Study Design

Type

Cross-Sectional (n=75)

Structured PICO

Is non-dipping blood pressure status associated with poorer sleep quality in relatively young patients with newly diagnosed stage 1 hypertension?

Population

75 relatively young patients with newly diagnosed stage 1 hypertension and no prior anti-hypertensive medication use, evaluated for sleep quality and blood pressure dipping status.

Exposure

Non-dipping blood pressure status on ambulatory BP monitoring

Comparator

Dipping blood pressure status on ambulatory BP monitoring

Outcome

Sleep quality assessed by the Pittsburgh Sleep Quality Index (PSQI)patient reported

Poor sleep quality is significantly associated with non-dipping blood pressure patterns in newly diagnosed hypertensive patients, suggesting sleep evaluation may help identify higher-risk individuals.

Main Result

Odds Ratio: 2.955 (95% CI 1.127–7.747)

Abstract

BACKGROUND: Sleep is a basic physiological process. Normal sleep yields decrease in sympathetic activity, blood pressure (BP) and heart rate. Those, who do not have expected decrease in their BP are considered "non-dippers". We aimed to determine if there was any association between the non-dipping status and sleep quality, designed a cross-sectional study, and enrolled and evaluated the sleep quality of relatively young patients with an initial diagnosis of hypertension. METHODS: Seventy-five consecutive patients, diagnosed to have stage 1 hypertension by their primary physicians, were referred to our study. Patients had newly diagnosed with stage 1 hypertension. Patients with a prior use of any anti-hypertensive medication were not included. Eligible patients underwent the Pittsburgh Sleep Quality Index (PSQI), which has an established role in evaluating sleep disturbances. All patients underwent ambulatory BP monitoring. RESULTS: There were 42 non-dipper patients (mean age = 47.5+/-11.9 years, 24 male/18 female), as a definition, 31 dipper hypertensive patients (mean age = 48.5+/-12.8 years, 21 male/10 female) and two with white coat hypertension. Daytime systolic and diastolic mean BPs were not significantly different between the two groups. Night-time mean systolic and diastolic BPs were significantly higher in non-dippers compared with dippers. PSQI scores, globally, were significantly higher in non-dippers compared with dippers. Total PSQI score was not correlated with body mass index. It was noticed that, individually, sleep quality, sleep efficiency and sleep disturbance scores were significantly higher in non-dippers. Being a poor sleeper in terms of high PSQI score (total score>5) was associated with 2.955-fold increased risk of being a non-dipper (95% confidence interval 1.127-7.747). CONCLUSION: We showed that the risk of having non-dipping hypertension, a risk factor for poor cardiovascular outcomes among hypertensive individuals, was tripled (odds ratios) among poor sleepers. We think that evaluating sleeping status and sleep quality among the hypertensive population may help unmask non-dipper hypertension, enabling physicians to treat appropriately.