Dados do Trabalho

Título

Sleep irregularity and the association with hypertension and blood pressure levels: the ELSA-Brasil study

Introdução

Obstructive sleep apnea (OSA) is one of the most studied sleep disorders associated with hypertension (HTN). However, other sleep disorders may have a role in HTN independently OSA.

Objetivo

To evaluate the associations of sleep irregularity, sleep duration and insomnia with HTN and blood pressure (BP) levels.

Métodos

Participants from the ELSA-Brasil performed a clinical evaluation including subjective and objective sleep duration for 7 days, insomnia assessment using the CIS-R questionnaire and OSA diagnosis (defined by apnea-hypopnea index ≥15 events per hour by polygraph). To quantify sleep irregularity, three parameters from the one-week actigraphy monitoring were used: recovery sleep at the weekend (catch-up-sleep); 2) standard deviation (SD) of sleep duration; 3) SD in sleep-onset timing. We developed progressive models adjusting for age, gender, race, body mass index, alcohol consumption, physical activity, urinary sodium excretion and OSA. A multivariate analysis was developed to determine the independent association of sleep irregularity variables, subjective/objective sleep duration and insomnia with HTN and BP levels. We performed two independent analyses using different definitions for HTN: 1) the traditional definition (BP ≥140x90mmHg and/or previous use of antihypertensive medications); 2) the American HTN definition (BP ≥130x80mmHg and/or previous use of antihypertensive medications).

Resultados

We studied 1,720 participants (age 49±8 years; 44.7% men). Approximately 20% had insomnia and 33% had OSA. The frequencies of HTN were 27% and 43% using the ≥140x90mmHg and ≥130x80mmHg definitions, respectively. No significant associations were observed for the sleep variables studied using the traditional HTN definition. In contrast, using the ≥130x80mmHg definition, we found that sleep irregularity variables were independent associated with HTN: SD >90 min (OR 1,34; CI 95% 1,06-1,70) e catch-up-sleep >90 min (OR 1,31; 1,03-1,67). In addition, the SD of sleep duration >90 min was independently associated with systolic BP (β 1,92; CI 95% 0,28-4,56) and diastolic BP (β 1,41; CI 95% 0,24-2,58) even after adjustments for antihypertensive medications.

Conclusões

Sleep irregularity, but not sleep duration or insomnia, was associated with HTN (by the recently definition adopted by the American Guideline) and higher BP levels. These data suggest a potential role of circadian patterns on cardiovascular diseases.

Palavras-chave

sleep duration, Sleep irregularity, obstructive sleep apnea, hypertension, blood pressure