by Claire Pesterfield
Paediatric Diabetes Specialist Nurse, Children’s Services, Cambridge University Hospitals NHS Foundation Trust
management of type 1 diabetes mellitus has changed over the years, with
the modification of lifestyle playing an important role in today’s
treatment modalities. One such aspect is that of physical activity and
The American Diabetes Association (ADA 1997) stated that:
levels of exercise, including leisure activities, recreational sports
and competitive professional performance, can be performed by people
with type 1 diabetes who do not have complications and are in good
blood glucose control”.
For some people, a weekly aerobics class
will suffice, but for others a more extreme activity is required, hence
the increase in the number of people with diabetes participating in
sports such as climbing, diving and marathon running.
article looks at the experience of one such person (me!), climbing
Mount Kilimanjaro - the highest free-standing mountain in the world -
and what lessons can be learned to help nurses empower their patients
to undertake similar activities.
at 5895m (19340ft) high, Mount Kilimanjaro is described as the ‘Roof of
Africa’. There is a misconception that it is ‘easy’ to climb because no
technical climbing ability is needed, however, people die every year
trying. The Kilimanjaro National Park Authority estimate that only
40-50% of climbers successfully reach the summit and return.
September/October 2004, three groups of climbers, 25 with diabetes,
took on the challenge of reaching the summit of Kilimanjaro in order to
raise funds for Diabetes UK. By the time the last group had returned,
everyone had succeeded in reaching the top and raised nearly £200,000
for diabetes research. Everyone will have their own story of how they
got to the top, but we all learned that diabetes is no barrier to
achieving a dream if you work and prepare hard enough to achieve it.
story for me started 12 months before the climb when I decided to fill
in the application form, talk about it with my Diabetes Specialist
Nurse and started to train. The training would have a dual purpose –
not only would it ensure that I was fit enough to undertake the
challenge, but it would also show how my diabetes would be affected by
exercise. By measuring blood glucose levels both before and after
exercise at hourly intervals for 6 hours to 12 hours it was noted that
hypoglycaemia happened at differing intervals depending upon the
intensity and duration of the exercise undertaken. The intensity of
exercise was determined by the Karvonen formula for heart rate
calculation (Ackland 2003). Although this was useful in training, these
lessons cannot be related exactly to other situations such as high
altitude hiking, as environmental factors can interfere with the normal
physiological responses to exercise.
initially thought that this would be all I have to do, but then I
started reading to learn more about the environment I would be spending
10 days in and realised that things would not be that simple! The
height of Kilimanjaro is defined as extreme altitude as it sits above
5000m. Above this point, permanent human habitation is impossible,
oxygenation decreases and temperature levels plummet.
effects on the human body depend upon a person’s ability to acclimatize
and are listed in Table 1. All of these side effects can have a severe
impact upon the management of diabetes and must be considered before
undertaking a trip such as this. To add to these difficulties, the
management of diabetes itself can be further compromised due to the
extreme altitude and temperature ranges that are encountered. This is
where the help of an experienced and supportive Diabetes Health Care
Team cannot be underestimated.
Before the adventure began, our
kit had to be checked and packed. This turned out to be a bit of a
joke for all of us as we had to pack for a variety of weather
conditions from 30 degrees on the African plain to -25 degrees on the
summit – no mean feat when the weight limit is 15 kilos! Added to this
was the diabetes supplies I needed to take as well as the snacks and
hypo treatments. Excess packaging was reduced to a minimum, with
supplies for my insulin pump opened and the packaging being thrown
away. Insulin was drawn up into reservoirs and these pre-prepared sets
then contained in a sealed bag alongside a handful of alcohol swabs.
Although this increased the risk of infection, it was a risk I was
prepared to take.
All foodstuffs were chosen based on their
high carbohydrate content and their packaging again was kept to a
minimum. It was important to choose a variety of foods that would not
melt in the warm environments, but also would not freeze as the
temperature dropped. Concentrated fruit bars seemed to be the best
choice and at least would also offer a variety of flavours! Blood
glucose testing strips were piled into as few containers as possible,
and the luxury of using a new lancet for each blood test would just
have to wait!
managed to squeeze all my clothes, sleeping bag and diabetes kit into
my rucksack, it was time to head off to the airport, meet the team and
fly off to begin our adventure. The next 24 hours were spent sitting
down in airports, planes and buses, consequently, blood glucose levels
were a little higher than normal. This was easily counteracted by
increasing the basal rate on my insulin pump. Lunch was held in the
middle of the African savannah, with tables, chairs and even a
portaloo! Our drive through to our first camp allowed us to see herds
of giraffe and zebra as well as remote Maasai villages. The food was
not as different as we all thought it might be – they obviously had
done their homework about our nutritional needs and every meal was
packed full of carbohydrates as well as fresh fruit and plenty of tea,
coffee and Milo (a kind of hot chocolate which we all came to adore by
the end of the trek).
The trek started the following day after a
drive through more remote villages into the African lush rain forest.
This was a relatively short day as we had spent a lot of time meeting
our support crew and sorting out what gear to take up the mountain and
what to leave behind at our base camp. If every day was like this then
reaching the top shouldn’t be that hard! Day 2 would change any
misconceptions we had about the trek! The day consisted of walking
through more dense forest, which at times resembled a mud path due to
the high rainfall. This made walking hard work and although I had
reduced my insulin, it obviously was not enough. This is where the
convenience and flexibility of an insulin pump shines through as I
reduced my basal rate further which would take immediate effect (see
Table 2 for diabetes management during the trek). It was fortunate, as
the afternoon saw us gain 600m in height, the temperature drop
significantly and more hypoglycaemic attacks.
such as hiking, marathon running and cycling relies on the aerobic
system to provide the energy required. The fuels used are a mixture of
carbohydrates and fat. Protein also has a role but usually during very
prolonged activities and then only to a minor extent (ADA 1997). The
extent of carbohydrate utilization depends upon the intensity of the
exercise undertaken. High intensity exercise will use 100%
carbohydrates, with muscle glycogen and blood glucose being used most.
At lower intensities such as hiking and backpacking, circulating
hormones such as epinephrine mobilize fats from adipose stores to be
used as energy. However, these rules need to be adapted for working at
altitude as this creates an additional strain on the body. McKean
(2005) claims that initial exposure to altitude causes an increase in
the use of blood glucose as an energy source and a decreased reliance
on the use of fat stores. As a result, fatigue and hypoglycaemia are
more likely to occur at the same intensity of activity at altitude
compared to that of sea level, and therefore insulin requirements need
to be reduced.
Day 3 was a short day for walking but would
include an acclimatisation trek up to 4,100m on the Shira Needle. The
landscape had changed from warm, lush rainforest to heath land and
alpine desert which meant we were now exposed to chilling winds and
freezing mist. Our energy requirements increased in line with the
increase in altitude and we tried to stay warm. Frequent snacks were
needed to prevent glycogen stores from becoming depleted but the
altitude was now beginning to affect my appetite.
the risks of dehydration and altitude sickness it was necessary to
drink at least 3 – 5 litres of fluid a day. Drinking so much fluid
reduced the appetite, so compromise was reached by adding powdered
sports drinks to add flavour as well as carbohydrates. Hot drinks were
very welcome but caffeine intake should be reduced to minimise the
effects of Acute Mountain Sickness (AMS), so hot Milo was very
popular. However, the lack of caffeine can make hypoglycaemic warning
signs more subtle in some patients with Type 1 diabetes (Debrah et al 1996, Watson and Kerr 1999), so it is necessary to weigh up the potential risks individually.
each day of hiking it was important to replenish glycogen stores in
order to prevent blood glucose levels dropping during the night and to
ensure that there would be enough energy stores to continue the next
day. The risk of hypoglycaemia after exercise can be present for up to
48 hours after the activity due to the heightened insulin sensitivity
during muscle glycogen replenishment (ADA 1997) and therefore good
nutritional intake throughout the trek was vital.
There are a
number of studies that show that glycogen replenishment is best
achieved within the first six hours (and in particular the first two)
with high glycaemic foods that are rapidly absorbed into the blood
stream. On arriving in camp each evening, hot popcorn and more hot Milo
was available in the mess tent and everyone was encouraged to tuck in
as much as they could until the evening meal arrived.
altitude, temperature levels were beginning to drop. During the day,
they can reach up to 30ْC, but at night they can plummet to well below
zero. On average, the temperature will drop 1ْC for every 200m gained
in height. During the day it was important to stop the insulin from
getting too warm, but at night it was vital to prevent it from
freezing. This was achieved by having the insulin, blood glucose meter,
testing strips, and hypo treatment in the sleeping bag with you
overnight and wrapping it in a spare fleece (if there was one!).
the altitude increases it affects the body in peculiar ways. Add to
that the increased fluid intake necessary to reduce altitude sickness
means that it is nearly impossible to sleep through the night without
wanting to go to the loo! But it could also mean that the blood glucose
levels have risen to a higher level. Here lies a difficult but
important question. Do you fumble in the bottom of your sleeping bag to
find your meter and hope that it is warm enough to give you an accurate
reading before you step outside, or do you quickly get dressed, go
about your business and try to forget about the possible causes? To be
honest, most of the time, it was so cold and the level of exhaustion so
great, testing was not really an option in the middle of the night. However, to make up for it, the view from the toilet (usually a handy
large rock nearby) a spectacular clear sky with gleaming bright stars
was compensation enough!
As the next three days went by, the
walking became more arduous, the temperature dropped, the strain on the
body increased and energy levels waned. My blood glucose levels were
reading higher than I expected for the effort I was putting in and I
began to wonder if my meter was accurate. The normal symptoms of
hyperglycaemia were easily masked by my aching limbs, frequent loo
stops but I remembered reading an article about a group from Ireland
who climbed Kilimanjaro a few years before where they noticed that as
they climbed higher, insulin requirements actually increased (Moore et
Reaching the Summit
the summit attempt approached, I was confident that my diabetes would
not hold me back, but it would be down to the weather conditions, a bit
of luck and a lot of determination. My rucksack was packed full of food
and water and I decided to wear all the clothes I had, as the wind was
howling and the temperature had dropped to around -15ْC. I had packed
all the important equipment close to me as I did not want it to freeze,
or to stop to find it in my pack. I had also taped my infusion set from
my insulin pump to my body to prevent any chance of it being exposed to
cold air and freezing. We all left camp at 10pm and aimed to climb
through the night in order to reach the summit at day break where we
could all sit as a group on top of Africa and watch the sun rise.
worsened, with the temperature dropping. My water froze and every time
I stopped to catch my breath or eat a snack, I began to shiver with
cold. There was no point in testing as I could not be bothered to take
my four pairs of gloves off to find a finger to prick, let alone unzip
my jackets to find my meter! This was the hardest thing I have ever
done (or likely to do), but the images of my friends and family back
home who have supported me from the start kept me going, as well as the
chance to sit on top of Kilimanjaro and be warmed by the sun.
I made it to the top, but it was not the picture postcard that any of
the group had imagined. The weather had deteriorated into the worst
conditions for years with the temperature dropping to below -25ْC and
blizzard conditions. There would be no basking as the sun rose – it was
a quick cup of celebratory Milo, the obligatory summit photograph, and
a three hour trek back down to camp for a few hours sleep before we
were due to descend further to a lower camp.
Conclusion and Reflection
experience of ‘summiting Kilimanjaro’ has answered a lot of questions
and been an invaluable experience. Not only have I made a number of
great friends but I have also learnt that with the right research,
support and preparation, people with diabetes can and do achieve things
that were once thought inconceivable and unattainable. It should not be
used as a barrier to achieving goals, but as a motivating factor to
encourage and develop self-care skills and empowerment.
nurses, we have a role in supporting our patients in the achievement of
their goals, no matter what field we work in and by working together as
an equal partnership we can learn from each other.
are a number of people whose help and support were instrumental in the
success of this trip, some of which are listed below. Without them,
achieving my dream would not have been possible.
… and all the guys involved in Trek No 3, both climbers, guides and support crew.
Ackland J (2003) The Complete Guide to Endurance Training. London: A&C Black
ADA (American Diabetes Association) (1997) The Diabetic Athlete – Prescriptions for Exercise and Sports. USA sorry – cannot find one!: Human Kinetics
K, Sherwin R, Murphy J, Kerr D (1996) Effect of caffeine on recognition
of and physiological responses to hypoglycaemia in insulin dependent
diabetes. Lancet 347:8993;19-24
McArdle W, Katch F, Katch V (2001) Exercise Physiology – Energy, Nutrition and Human Performance 5th edition. USA Baltimore: Lippincott Williams & Wilkins
McKean R (2004) Optimal Fuel – fat, carbohydrates or protein? Nutritional information for high altitude sports. Available: http://www.scottishsport.co.uk/running/altitude3.htm
Last accessed 09.01.2005
Moore K, Vizzard N, Coleman C et al (2001) Extreme altitude mountaineering and Type 1 diabetes; the Diabetes Federation of Ireland Kilimanjaro Expedition. Diabetic Medicine 18:9;749-755
Watson J, Kerr D (1999) The best defense against hypoglycaemia is to recognise it: is caffeine useful? Diabetes Technol Ther. 1:2;193-200 Review