Short and long sleep duration linked to increased cardiovascular risk
MedWire News: Both short and long sleep duration are associated with an increased risk for cardiovascular disease in older adults, Australian research shows.
"Smoking, obesity, high-fat diets and physical inactivity are established behavioural risk factors for cardiovascular disease," write Christopher Magee (University of Wollongong, New South Wales) and colleagues in the Journal of Sleep Research.
"Recent research has also identified relationships between sleep duration and cardiovascular disease, which may have implications for further understanding behavioural contributors to cardiovascular disease."
But they add that "there have been some inconsistencies in the results of these studies."
To investigate further, the researchers examined associations between sleep duration and prevalent cardiovascular disease in a large, heterogeneous sample of adults (n=218,155) aged 45 years and older.
All of the participants completed questionnaires regarding usual sleep duration, and were asked whether they had ever been diagnosed with heart disease, high blood pressure, stroke, or diabetes.
Data regarding each participant's body mass index (BMI), gender, age, education level, employment status, marital status, alcohol consumption, smoking status, and physical activity levels were also collected.
The researchers found that, compared with people with an average sleep duration of 7 hours (=7-<8 hours), those who slept for 6 hours (=6-<7 hours) were significantly more likely to have heart disease, diabetes, stroke, or high blood pressure, at odds ratios (ORs) of 1.11, 1.15, 1.25, and 1.08, respectively, after accounting for age, BMI, smoking, and other variables.
Participants who had an average sleep duration of 9 hours or more were also significantly more likely to have heart disease, diabetes, high blood pressure, or stroke than those with an average sleep duration of 7 hours, at ORs of 1.14, 1.25, 1.04, and 1.50, respectively, after adjustment for potential confounding factors.
Magee and team conclude: "The present study identified significant relationships between sleep duration and a range of cardiovascular conditions in a large sample of middle aged and elderly Australian adults."
They add: "Evidently, there is a need for more prospective research to clarify ways in which sleep duration and cardiovascular disease are related. This needs to involve investigation of relevant physiological and behavioral mechanisms, and formal analysis of how these associations vary by important sociodemographic variables."
By Mark Cowen