Getting enough sleep is crucial for health, but researchers now found that maintaining a consistent sleep schedule is just as important. A recent study suggests that irregular bedtimes could raise the risk of cardiovascular events.
While much is known about how sleep duration affects health, less is known about the role of sleep-wake cycle regularity. The latest research published in the Journal of Epidemiology & Community Health investigated how variations in sleep and wake times impact cardiovascular health and found that even individuals who get the recommended amount of sleep may face a higher risk of heart attacks and strokes if their sleep patterns are irregular.
"Findings from this study suggest that more attention needs to be paid to sleep regularity in public health guidelines and clinical practice due to its potential role in cardiovascular health," the researchers wrote.
The researchers came up with the findings after evaluating more than 70,000 people were part of the UK Biobank study using activity trackers. The participants were aged between 40 to 79 and did not have any history of major cardiovascular events.
The researchers monitored the sleep patterns of each participant for 7 days and calculated their Sleep Regularity Index (SRI) score. While a SRI core of more than 87 was categorized as a regular sleep pattern, having a score of less than 72 was considered an irregular sleeper. Moderately irregular sleepers fell in between these two groups.
Using hospital records and data from death registries, the researchers tracked the incidence of cardiovascular deaths, heart attacks, heart failures, and strokes among the participants over the next 8 years.
The study found that individuals with irregular sleep patterns had a 26% higher risk of experiencing a major cardiovascular event compared to those with a regular sleep-wake cycle, while those with moderately irregular sleep patterns were 8% more likely to face the same risk.
This is after accounting for age, physical activity levels, discretionary screen time, fruit, vegetable, and coffee intake, alcohol consumption, smoking, mental health issues, medication use, and shift work.
Upon detailed analysis, researchers noted an almost linear relationship between lower SRI scores and a higher risk of cardiovascular events.
The amount of sleep recommended for adults aged 18 to 64 is 7 to 9 hours and 7 to 8 hours for those 65 and older. The study noted that a greater proportion of regular sleepers met the recommended sleep duration compared to irregular sleepers: 61% versus 48%.
"But when the impact of clocking up the recommended sleep quota was taken into account, the risk of a major cardiovascular event wasn't offset in irregular sleepers who achieved this, although it was in moderately irregular sleepers," the news release stated.
