Circadian preference and stroke characteristics: A descriptive study

There is evidence that circadian misalignment is linked with an increased risk of stroke and that circadian preference is linked with rehabilitation outcomes after stroke. Circadian preferences refer to preferences based on individuals' characteristics in respect of the timing of physiological functions that are typically assessed by self-report questionnaires. This study set out to explore this relationship by examining whether there was an association between circadian preference and stroke characteristics in a sample of stroke outpatients, considering the time of stroke onset, the topography of the stroke and the resulting disability. We also examined whether sleep complaints (snoring, insomnia, sleep apnea) were associated with circadian preferences (i.e., morning-, evening-, and intermediate-types). We also compared circadian preferences and comorbidities in this sample, matched by age and sex, with those of healthy controls who took part in an epidemiological study (EPISONO) comprising a representative sample of the population of the city of São Paulo, Brazil. Most of our sample in both groups were morning-type, and in the stroke group, ischemic stroke was the most common type. There was an increased risk for sleep apnea among evening-types, and a higher prevalence of diabetes in the evening- and intermediate-types. We found no association between circadian preference and the time of stroke onset, or with wake-up stroke. We found a low prevalence of evening-type participants in our sample of controls (2.9%) and in the stroke group (1.7%). This investigation showed a similar circadian preference (morning-types) in stroke outpatients and the general population.