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Current Issues International Health and Diabetes
Figure 1: Prevalence of Diabetes in 2007 and The difficulty of assessing diet and nutritional data in free-living
Projections for 2025, with Projected Per Cent Changes
individuals makes this as challenging as collecting physical activity
data in many resource-limited countries. Studies in South African
99.4 blacks have shown a trend of increasing consumption of fat and
100
decreasing consumption of carbohydrates in both urban and rural
80.3 areas.
16
However, the notion of increased consumption of fat as a
80
marker of urbanisation and westernisation of the African diet was not
67
64.1
confirmed in our own studies, in which we found the highest
60
53.2
consumption of fat in rural Cameroonians compared with urban
46.5
44.5
40.5
Cameroonians, black Jamaicans and blacks in Manchester.
17
We
40
32.7
28.3 postulated that the excess consumption of fats in the rural area is
24.5
18.7 more than compensated for by very high levels of physical activity.
20
16.2
10.4
Whatever the interplay in the lifestyle factors, there has clearly been a
81.4% 48.4%80.1% 43.4% 101.7%20.6% 76.3%
Number of people with diabetes (millions) remarkable increase in the prevalence of obesity in many African0
AFR EMME EUR NA SACA SEA WP
communities. Abubakari et al.
18
pooled data from studies in west
2007 2025
African adults and showed that the prevalence of obesity has more
1
Source: IDF Diabetes Atlas. AFR = Africa; EMME = Eastern Mediterranean and Middle East;
than doubled in urban regions from 7 to 15% over a 15-year period
EUR = Europe; NA = North America; SACA = South and Central America; SEA = South-East
from 1990 to 2004. Women and urban dwellers had a significantly
Asia; WP = Western Pacific.
higher prevalence of obesity compared with men and rural dwellers,
Figure 2: Prevalence of Type 2 Diabetes in
respectively. Similar results have been reported in other African
Cameroon, 1994–2003 populations.
16,19
Data from repeated surveys in the same areas
in Cameroon over a 10-year period showed an overall increase in
9
prevalence of overweight and obesity in the rural site (increase of 54%
8
in women and 82% in men) and of central obesity in the urban site
7
(increase of 32% in women and 190% in men).
20
The public health
6
challenge posed by obesity in these populations is far from over as
excess weight is perceived positively as a sign of wealth, with a5
positive association between socioeconomic status and obesity seen
4
in developing countries in contrast to the negative association in
Prevalence (%)
3
developed countries. The stigma associated with HIV-related weight
2
loss only further aggravates the social perception of slim body size.
1
The prevalence of diabetes increases with age. However, the majority of0
1994 1998 2003
people living with diabetes in SSA countries are in the 45–64 year age
Urban men Urban women Rural men Rural women
group, in contrast to developed countries, where the highest
7
Prevalence standardised according to new world population distribution.
prevalence of diabetes is in those 65 years of age and above
21
(see
sectional surveys over a 10-year period (1994–2004) revealed an Figure 3). This underscores the point that the economic burden of
almost 10-fold increase in diabetes prevalence (see Figure 2).
7
Most of diabetes in developing countries will be compounded by its effect on
the classic risk factors have been reported to be associated with the working age group.
diabetes in Africans. However, a lot of these papers are based on
empirical evidence or poorly measured lifestyle exposure. Morbidity and Mortality
Urbanisation, resulting in increased levels of physical inactivity and SSA is currently struggling under a multiple disease burden that is not
high-fat diets, has been described as the major driver of increasing really getting lighter over the years. The emerging and increasing
levels of obesity and diabetes. Many studies have shown a distinct prevalence of obesity, diabetes and non-communicable diseases is not
rural–urban increased risk of obesity and diabetes,
8,9
with a lengthier accompanied by any marked improvements in infections or
stay in the urban environment conferring a higher risk.
10,11
Even though undernutrition; many studies have reported high rates of co-existence of
the idea of lower physical activity in urban areas compared with rural obesity and undernutrition in the same communities and even in the
areas is intuitively plausible, most of the studies reporting physical same households.
22
This means that diabetes has to compete for scarce
activity levels have used very crude questions to obtain these data. A financial and healthcare resources with infections and undernutrition. Of
few studies have used validated physical activity questionnaires to course, this does not sound like a recipe for success. Prevalent
demonstrate this urbanisation gradient,
12,13
as well as the increased risk undiagnosed diabetes is very high – about 80% in data from Cameroon.
23
of diabetes associated with reduced physical activity levels.
14
There are Even in known diabetes patients, control is often very poor. Only about
no studies that have used objective assessment of physical activity; one in four known diabetes patients in a population survey in Cameroon
neither are there any studies that have documented temporal trends of had optimal fasting blood glucose levels.
23
In a study in Ethiopia of 105
physical activity levels in communities using comparable methids. The diabetes patients seen by one physician, despite a low body mass index
adoption and use of the World Health Organization (WHO) STEPS Global (BMI) – median BMI was 20.6kg/m
2
– mean glycated haemoglobin
Physical Activity Questionnaire for surveillance of habitual physical (HbA
1c
) was 11.3±2.8% and 68% of patients had an HbA
1c
over 10%.
24
activity by many SSA countries
15
will hopefully provide some answers
in the near future about trends in population levels of physical activity, Published data on acute complications of diabetes in SSA are scarce, but
despite the limitations of self-reported physical activity. nonetheless point to the fact that these are more common than in
14 EUROPEAN ENDOCRINOLOGY