Pre-Obesity Markers In Shift workers and non-shift workers

Multiple studies have recently shown that working rotating night shifts is
associated with an increased BMI and a higher risk for developing overweight
and obesity. In addition, there is growing evidence that chrono-disruption and
mis-timed eating have deleterious effects on metabolic health and consequently,
shift work is linked to the risk of chronic diseases such as cardiovascular
disease, type 2 diabetes and several types of cancer. Disruption of the
internal circadian timing system and concomitant sleep disturbances is thought
to play a critical role in the development of these health problems, but also
other factors may play a role. To further address how night shift work impacts
metabolic health population-based mechanistic study data is needed. The
European Shift2Health project will focus on providing population-based
mechanistic data on a wide range of biomarkers of metabolic disease risk that
will advance our knowledge on the short- and long-term health effects related
to night shift and eventually will help in designing and applying efficient
prevention policies.

The primary objective of this study is to compare lifestyle factors, dietary
behaviours, environmental factors and pre-obesity risk markers between shift
workers and non-shift workers from the industrial sector and the health care
sector.

The PROMIS study is a cross-sectional study comparing lifestyle factors and
pre-obesity marker between shift workers and non-shift workers. In addition,
the shift workers are nested in an additional mechanistic component of the
study investigating differences in pre-obesity marker between different shifts.

All participants will have a study day at the location of employment before a
day shift (shift workers) or at the start of a regular working day (non-shift
workers). This study day will take approximately 1 hour and 30 minutes. Prior
to the study day participants will complete a baseline questionnaire (±45
minutes), collect morning spot urine and faeces samples, which will be handed
in on the study day. During the study day, participants* body composition will
be measured, a fasting blood sample, and hair sample will be collected. Hair
sampling is painless but venapunctures can occasionally cause a local hematoma
or bruise and some participants may report pain or discomfort. All participants
will perform a food preference and perception task as well as an identification
test for smell and taste. After having breakfast, participants will complete
one final questionnaire (±5 minutes). At the end of the study day, participants
will be invited to report their food intake via Traqq®; shift workers will
complete a total of six 2hR-days and non-shift workers a total of three
2hR-days, within a two-week period. Responding to the 2hR prompts will take on
average 5 minutes.

The shift workers will have some additional measurements, i.e., collection of
two 24-hour urine samples; once the day before the study day, and once during
the night shift measurement day. During the study day (before the day shift),
they will collect a dried blood spot and tongue swap, which will be repeated
after the day shift. Within the following two weeks there will be another
measurement day, during a night shift, where the night shift workers repeat the
dried blood spot collection and tongue swap. In addition, they will once more
complete the short questionnaire from the study day (±5 minutes). Between the
study day and the night shift day, the shift workers wear a MotionWatch to
assess physical activity and sleep.