Study finds chronic disruption can cause heart and kidney disease

University Health News today posted an article Chronic Sleep Disruption Can Cause Heart And Kidney Disease. The subject of the article is pretty self-explanatory, based on the title, and it discusses research conducted at the Peter Munk Cardiac Centre of the Toronto General Hospital (Toronto, Ontario, Canada).

Dr. Michael Sole, Cardiologist and founding director of the Peter Munk Cardiac Centre and Professor of Medicine and Physiology at the University of Toronto suggests that shiftworkers working on a rotating schedule should try to maintain the same shift for a month at a time to reduce the circadian disruption.

Study finds returning to night shift increases errors

The Chicago Tribune today published an article Shift work takes focus off the job that discusses a Harvard Medical School study which found that shiftworkers returning to the night shift after a stretch of day shifts are less able to maintain alertness and focus. The researchers found test subjects made errors in visual search tests.

The study's lead researcher pointed out that this can have real consequencces. For instance, "An airport security screener, for example, switching from day to night shifts without a break could be affected and make errors on a visual search test, such as screening luggage for weapons."

The article concludes by citing one shiftworker, a nurse named Kathy Koch, and says "Sleep for Koch, fortunately, comes easily. 'I can sleep in the sun,' she said. 'I can sleep anywhere, anytime.'"

I need to comment on this last line because it's a little pet project of mine. When people are able to sleep in the sun, anywhere, anytime, that generally is not a good thing. In most cases that's a sign of accumulated sleep deficit. A person may not be getting enough sleeping time, or may suffer from sleep apnea or some other sleep disorder. Either way, characterizing that as "fortunate" is putting a positive spin on what is far more likely to be a health and safety concern.

Funny shiftwork stories

One of the things that adds color to the life of a shiftworker, and to the shiftwork world in general, are the personal stories. I recently ran across a blog post in which a shiftworker on an -8-hour rotating shiftwork schedule dreamt he had hit his snooze alarm and then woken up at the time his shift started. He raced to his job and found that he was 8 hours early for his shift. I've heard this type of story many times.

Do you have any personal stories, funny or otherwise, that you'd like to share? I look forward to hearing from you.

Ed

Source: http://loveallbooks.blogspot.com/2007/03/strange-memories.html

Shiftwork schedule factors: speed and direction of rotation

Adapting to rotating shifts can be affected by the speed of rotation and the direction of rotation. Speed of rotation means the number of consecutive day, evening, or night shifts before a shift change occurs. Direction of rotation means the order of shift change:

• A forward rotation is in the clockwise direction, from day to evening to night shift.
• A backward rotation is in the counterclockwise direction, from day to night to evening shift.

Different rotation speeds also affect a worker's ability to get used to change of shift times. We have already talked about the same situation under permanent versus rotating shifts. Longer rotations (for example, three to four weeks of working the same hours) are sup-posed to allow workers more time to get used to night shifts.

However, workers usually return to a day schedule on their days off. A fast rotation (every two days, for example) allows no time to get used to night work. Some researchers prefer the fast rotation, because the worker quickly gets through the tough shifts and then has a couple of days off. Very fast rotations are used in Europe more than in America.

Direction of rotation can affect the ability of circadian (daily body) rhythms to adapt to the change in work times. Sleep, for example, is a circadian rhythm because each person sleeps for part of every day. Some researchers suggest that a forward, or clockwise, rotation is better for helping a worker adjust to new sleep times.

This suggestion was made because it is easier to go to bed later and wake up later than earlier. Our body rhythms make us feel more awake and alert in the early evening. This makes it harder to fall asleep earlier. Backward rotations work against the body rhythm by forcing the worker to go to sleep earlier and earlier.

Although we don't have hard and fast numbers, it seems that back-ward rotation schedules are used frequently in the United States. It is not completely clear why. It is partly because of custom (We always did it this way) and partly because workers like the “long change.”

In the long change, workers pick up an extra day off when going to evening shifts after night shifts. This happens because evening shift starts late in the day, which leaves most of that day free for non-work activities.

We'll continue this discussion of shiftwork schedule factors.

Other recent posts on shiftwork scheduling include:

• Shiftwork schedules: fixed or rotating
• Best practices for managing a shiftwork operation

Ed

Source: Plain Language About Shiftwork (NIOSH)

Shiftwork schedules: fixed or rotating

Although some might think workers who always work the night shifts adapt or get used to their work times -- usually the longer somebody does something, the easier it becomes. Over time, many nightshift workers develop techniques to better maintain their alertness but the fact is most nightshift workers are not able to fully adapt and therefore, at least some time, they work in the fog of fatigue.

This fatigue happens because most nightshift workers revert to a day schedule when they're off from work, since that's when most of the world is awake during the day and sleeping at night. Also, many of the errands and chores that accumulate while we're working must be done during the day.

As a result most nightshift workers return to a day schedule so they never completely allow their sleep and body rhythms to adapt to being awake at night. They also sleep less during the day, so they don't recover from fatigue. This fatigue can carry over from day to day. Over several days, fatigue can accumulate to unsafe levels.

People working rotating shiftwork schedules face a similar situation. Because the shift times are always changing, they can never completely adapt to a set shift work schedule. Rotating shiftwork schedules are often used because they are considered fairer to all workers. Everybody in the workforce takes their turn at both the popular and unpopular shifts. Rotating shiftworkers are always trying to get used to changing work times.

This is not easy, which is why rotating shiftworkers have more complaints than other workers about physical health and psychological stress. Research has shown that rotating shifts have special features that might affect a person's ability to get used to the schedule.

I'll talk about those special features in future posts. -- Ed

Source: Plain Language About Shiftwork (NIOSH)

Highway Patrol's sleep schedule on TV

The local NBC affiliate in Bismarck, North Dakota, USA ran a piece of the effect of shiftwork, in this case a rotating shiftwork schedule, on police officers sleep schedule. You can view the piece, with a brief write up as well, at the KFYR website.

It is important for the general public and policy makers to recognize the issue of sleep and alertness for police and other public safety officals. The public relies on the availability of these services but may not always appreciate the challenges of protecting public safety 24/7. Way to go KFYR.