Managing shiftwork and diabetes does require planning ahead. There are several issues to be considered, particularly if you are using insulin. The person with Type 2 diabetes who is managing with diet and exercise should also be aware of potential problems with control.
In the past, people with diabetes were often denied certain jobs. Now, with the use of blood glucose monitoring, various insulin regimens and with better awareness of how to control diabetes, there are more job opportunities, including those requiring working shifts.
Our bodies are influenced by internal ’clocks’ called circadian rhythms. Among other functions, these clocks tell us when to sleep and when to be awake. Shiftwork disrupts this balance and can result in mental and physical stress affecting blood glucose control.
Stress affects the body by causing the release of hormones that lead to increased levels of glucose in the blood. This, in addition to different patterns of eating and changes in activity/habits while working shifts, can result in unpredictable fluctuations in blood glucose control.
Self-monitoring of blood glucose (SMBG) can be the most effective tool to help determine patterns of blood glucose control and identify problem areas. Understanding blood glucose can help you to anticipate situations where you may experience high or low blood glucose and allow you to plan ahead to prevent these situations from occurring.
It is important to self-monitor on a regular basis so your usual pattern of control is known. When changing shifts, monitor at various times to assess your blood glucose patterns while working. For example, test before a ’new’ meal or snack times, when physically active and when insulin or diabetes pills are working the hardest. Record the results and situations in a logbook to help you make appropriate adjustments.
Working shifts usually requires some modification in all areas of diabetes self-management. Adjustments in insulin, diabetes pills, exercise plan and meal pattern may be necessary. Generally, working days to nights with two or three weeks on each shift presents the fewest problems. The midnight shift is the most challenging.
Meal planning is the foundation of diabetes management regardless of the type of diabetes, medication used or shift worked. The basic guidelines include evenly spaced meals (four to five hour intervals) and snacks (if required), and consistent types and amounts of food. A dietitian should advise you on the specific details based on your individual needs.
When working the afternoon shift, the only change to the meal plan may be to include a larger evening snack to match increased physical activity, particularly if you use insulin or diabetes pills.
The midnight shift requires you to adjust your meal plan significantly, allowing for the greater amount of food to be eaten from approximately 10 p.m. to 8 a.m. with an adequate amount of food for the periods of sleep during the day – especially for those on insulin or diabetes pills.
If you use insulin, you will have to consider the time when insulin starts to work and peaks (when it is working the hardest) as well as changes in physical activity when planning meals and snacks.
If you take diabetes pills, be aware of the time when the pills will peak and the length of time they are effective.
If you have Type 2 diabetes, and are managing with diet and exercise, pay attention to the basic guidelines even though you may have more flexibility with timing meals.
Other considerations when meal planning for shiftwork include: availability of food – are there only vending machines or is there appropriate storage for bagged lunches; is there the possibility of unexpected overtime or double shifts; are sugar-free drinks available; are meals and breaks at set times and are they appropriate; and, if required, are you able to keep food with you for snacks or treating hypoglycemia (low blood sugars).
Changes in the level of physical activity while working shifts can result in fluctuations in blood glucose control. If the work is physically demanding, particularly at unexpected times, the person using insulin or diabetes pills may be at risk for hypoglycemia. More sedentary work may allow you to assess and manage these problems appropriately at the time and to plan for future situations.
Your regular exercise plan may have to be modified to fit the change in shifts. Generally, the best time to exercise is after a meal when blood glucose tends to be higher. If working an evening shift, you may want to exercise after lunch. When returning home from the midnight shift, exercising after the morning meal is often a good time. The activity may help to relax you and allow you to sleep better.
For those on insulin (and sometimes those taking diabetes pills) there is a risk of hypoglycemia unless adjustments in food intake, insulin, and activity are made before working the midnight shift. Recognizing when and why hypoglycemia occurs and being prepared with SMBG and appropriate treatment can reduce the danger. Generally, hypoglycemia can occur with increased physical activity, during peak action of insulins or diabetes pills, and with delayed or inadequate meals or snacks. Carry a source of fast acting carbohydrate wit you at all times to treat low blood sugars fast and effectively.
If you are taking pills to treat diabetes, you may have to change the time you take them when working shifts. The pills should be taken prior to a meal, usually breakfast and sometimes suppertime, and should be spaced evenly within the day.
Insulin adjustments are usually necessary when working shifts. Insulin can be delayed one to two hours without affecting diabetes control. This may be all that is required to manage the afternoon shift. If extra food is consumed later in the day, a slight increase in the suppertime insulin may be needed.
The goals for adjusting insulin over the midnight shift are to provide the right amount of insulin to match the change in food consumed; to avoid excess insulin to prevent hypoglycemia; to try to avoid insulin peaks during physical activity; and to reduce the amount of insulin during the sleep period.
Together, with your Diabetes Educator, you can plot a graph of times of wakefulness and sleep, meals, insulin actions and physical activity, including results of self-monitoring. A graph can be the easiest way to identify and overcome potential problems stemming from having diabetes at work.
Remember, it is important that you discuss these issues with your diabetes health team to develop written plans for meals, exercise, insulin adjustments, managing hypoglycemia and SMBG for each shift worked.