Dados do Trabalho

Título

Chronotype and sleep quality in the previous month after acute myocardial infarction

Introdução

Currently 60% of the population identifies with an indifferent chronotype, 40% as morning or afternoon. Being morning is a protective factor for several diseases, while afternoons have more complaints about sleep quality and health.

Objetivo

To evaluate the chronotype and quality of previous sleep in patients after the first acute myocardial infarction (MI).

Métodos

Descriptive study, carried out in a cardiology intensive care unit in the city of São Paulo. Patients ≥ 18 years old, with first MI, Glasgow 15 and spontaneous ventilation were included. Chronotype was assessed using the Morningness-Eveningness Questionnaire, where higher scores indicate mornings and lower afternoons. For sleep quality, the Pittsburgh Sleep Quality Index (PSQI) was used, where a score > 5 indicates poor sleepers. Qualitative variables were described in relative frequencies and quantitative variables in median, first and third quartiles, as they did not adhere to the normal distribution in the Shapiro-Wilk Test. The relationship between the chronotype and quality of previous sleep variables was obtained by the Pearson correlation test, which assumes values between -1 and 1, the negative coefficient value presents an inversely proportional correlation and the positive value a direct relationship between the variables. A significance level of p ≤ 5% was considered.

Resultados

Eighteen patients were evaluated, 94.4% male and median age of 57.5 (48.5-64.5) years. The antecedents were systemic arterial hypertension (64%), smoking (55.6%), previous snoring (50%), diabetes (38.9%), dyslipidemia (27.8%) and alcoholism (22.2%). Chronotypes were morning (22.2%), moderately morning (38.9%) and indifferent (38.9%). Most were classified as poor sleepers (77.8%) with a median of the total score of 7.5 (5.7-10.2). The PSQI components with the worst scores were poor sleep quality (38.9%), sleep duration between 5-6 hours (27.8%) and sleep latency >45min (22.2%). Pearson's test showed a moderate and proportionally inverse correlation (-0.52, p=0.027), revealing that individuals with morning chronotype had better sleep quality in the last 30 days.

Conclusões

The morning chronotype and poor sleep quality in the 30 days before the MI were predominant. Poor sleep quality, high latency and short duration were the main factors responsible for poor sleep quality. Morning chronotype showed a moderate correlation with better sleep quality in the last 30 days before the first MI.

Palavras-chave

Sleep; Myocardial Infarction; Sleep Deprivation