38 / 88
CARDIOVASCULAR JOURNAL OF AFRICA • Volume 28, No 4, July/August 2017
240
AFRICA
the values determined in the women’s labour force from Douala
(36%, based on BMI),
17
and similar to the prevalence of obesity
among urban southern women (33%)
18
and rural southern
women (33%).
19
Based on WC measures, in our study, the prevalence of
obesity in southern women was 100%, versus 82% for northern
women. Our data are higher than that obtained in urban
southern women (43%), based on WC.
17
Based on BMI, our
data showed that the prevalence of obesity in northern men was
21%, versus 7% for southern men, which were higher and lower,
respectively, than that from the men’s labour force from Douala
(18%, based on BMI).
17
Based on WC measures, in our study, northern men displayed
higher prevalence of obesity compared to southern men (40
vs 30%). These values were higher or lower than the obesity
prevalence determined for the men’s labour force from Douala
(32%, based on WC).
17
Recruitment methods, population sizes
and/or cut-off values for determination of obesity prevalence
may have accounted for these differences.
Strong and positive correlations existed between SBP and
WC, SBP and BMI, and DBP and WC among the northerners.
In the southern rural zone of Cameroon, obesity in women was
not correlated with blood pressure and blood glucose values due
to their farming activities, which can be equated with permanent
physical exercise.
19
Increased DBP and BMI in the north may have
been due to a lack of physical activity (95%), which appeared to
be much higher among northerners than among southerners
(70%) or the overall Cameroonian population (39%).
14
Higher WC and BMI values observed among southerners
could have been related to their food habits and/or lifestyle,
despite comparable total energy intakes observed in south
and north Cameroon.
8
Southerners were characterised by a
significantly higher fat consumption than northerners.
8
In
addition, our study showed that crude and refined palm oils rich
in saturated fatty acids (45–55%) and mono-unsaturated fatty
acids (38–45%)
20
were the oils mostly used by southerners. A
recent report has shown that the replacement of polyunsaturated
fatty acid with saturated fatty acid during a hypercaloric state
was accompanied by modest weight gain as well as increased
markers of endothelial dysfunction and insulin resistance in
healthy, normal-weight individuals.
21
The higher prevalence of obesity among southerners could
also have been related to the high percentage of individuals
consuming alcohol occasionally or regularly (92%), compared
to the low percentage (1%) of northerners consuming alcohol,
for cultural reasons. Our data corroborate a previous study
performed on Cameroonians from urban workplaces, showing
that the prevalence of obesity was positively correlated with
excessive alcohol consumption.
17
Among southerners, strong positive correlations existed
between lipid parameters and other cardiovascular risk factors
studied (hypertension and diabetes). Palm oil, rich in saturated
fatty acids and consumed by southerners, is a well-recognised
risk factor for CVD and metabolic diseases, as it induces a larger
increase in plasma concentrations of TC and LDL-C.
11
According
to Keys, food composition, not only rich in cholesterol but also
in fatty acids, controlled plasma TC concentrations.
22
Brady
et
al
. showed that consumption of omega-6 poly-unsaturated fatty
acids is likely to contribute to insulin resistance.
23
Diets with a
high omega-3/omega-6 fatty acid ratio improve the plasma lipid
profile and are known to reduce obesity and improve insulin
resistance.
24
While fish and shellfish are the main sources of
omega-3 fatty acid,
25
the energy intake from fish in Cameroon
represents only 0.4% of the total energy intake.
8
BG, SBPandDBPwere significantlyhigher amongnortherners
than southerners, with northerners being characterised by
high carbohydrate consumption compared to southerners.
8
Consumption of food with a high glycaemic index may account
for increased BG levels and blood pressure among northerners.
Similarly, consumption of high glycaemic index foods in Japan
increased the risk of developing type 2 diabetes.
26
In our study, the
prevalence of diabetes in northern and southern Cameroonians
was similar or lower, respectively, compared to the world global
prevalence of diabetes estimated in 2004 at 9% among adults
aged 18 years and over.
27
More than 80% of deaths related to
diabetes occur in low- and middle-income countries.
28
It has been
shown that a healthy diet, regular physical activity, maintenance
of a normal weight and stopping smoking can prevent or delay
the onset of type 2 diabetes.
29
Providing adapted health-related
advice to northern and southern Cameroonians would certainly
contribute to reducing risk factors for CVD.
Age has been considered a non-modifiable risk factor for the
onset of CVD.
4
However, the CVD risk factors monitored in our
study did not increase with age. On the contrary, we observed
that BMI was higher in the 35–51-year age group, compared to
people in the 51–65-year age group; this could have been linked
to a modification of lifestyle. In a recent report, the increase in
mortality rate from CVD between 1990 and 2020 is estimated
to be 140% in men and 118% in women in sub-Saharan Africa
compared to 53% in men and 31% in women in developed
countries. This is probably due to a shift to a Western lifestyle
and an increased intake of calories in sub-Saharan Africa.
1,3
Conclusion
The prevalence of obesity was higher in southern Cameroonians
(especially women) compared to northern Cameroonians. Lipid
parameters (TC, LDL-C and TG) were positively correlated with
cardiovascular risk factors such as BG levels, SBP and DBP
among southern Cameroonians. The prevalence of diabetes and
high blood pressure was higher among northern than southern
Cameroonians, despite the lack of correlation between lipid
parameters and cardiovascular risk factors assessed among
northern Cameroonians.
The main objective of this pilot study was to attract the
attention of national health authorities and medical communities
to the impact of dietary habits on the increasing prevalence of
cardiovascular risk factors by comparison of the two main regions
of Cameroon. Hopefully, the risk factors uncovered by this study
will encourage public health authorities to promote (financially
and logistically) a widespread multicentre study, allowing
healthcare personnel to assess the looming health issues and to
eventually provide public health recommendations. Furthermore,
additional studies aimed at assessing food consumption and
lifestyle factors in these two populations would increase our
understanding of cardiovascular risk factors in Cameroon.
This study was supported by grants from the Van Buuren and Jaumotte-
Demoulin Foundation, de Meurs François Foundation and Defay Fund
(Universite Libre de Bruxelles). JDC was a recipient of a doctoral fellowship