Important health news has uncovered a hidden cause of illness. A study in the “British Medical Journal” has shown that shift work is linked to a higher risk of major vascular problems, such as heart attacks and strokes.
We’ve long known that shift work throws the body’s internal clock (circadian rhythm) out of whack. And we know that disrupted sleep patterns then lead to a higher risk of high blood pressure, high cholesterol, and diabetes. But as of yet, shift work’s link to vascular disease is controversial.
So a team of researchers analyzed the results of 34 studies involving over two million individuals. Shift work was defined as evening shifts, irregular or unspecified shifts, mixed schedules, night shifts, and rotating shifts. Control groups were non-shift (day) workers or the general population.
Among the 2,011,935 people in the studies, more than 17,359 had a coronary event. Nearly 6,600 had heart attacks, while nearly 1,900 suffered ischemic strokes caused by lack of blood to the brain. These events were more common among shift workers than other people.
Shift work was associated with a 23% higher risk of heart attack, 24% higher risk of coronary events, and a five percent higher risk of stroke. These risks remained consistent even after adjusting for other possible factors, such as unhealthy lifestyles.
Night shifts were associated with the steepest increase in risk for coronary events — 41%. However, shift work was not associated with increased death rates from any cause.
One of the important points from this is that shift work is becoming more and more common in the general population. A difficult economy leads to people accepting employment in whatever forms they come in. The study provided some numbers from Canada, where some of the researchers were based. In the period 2008-2009, 33% of workers were on shiftwork, of whom seven percent had heart attacks, seven percent had coronary events, and 1.6% suffered strokes.
The study suggests that screening programs could help identify and treat risk factors, such as high blood pressure and cholesterol levels. Shift workers could also be educated about symptoms that could indicate early heart problems. Finally, they say more work is needed to identify the most vulnerable groups of shift workers and the effects of modifying shift patterns on overall vascular health.
If you or someone you know does shift work, it’s important to at least be aware of these links. And consider making your lifestyle as healthy as possible to compensate for it.