CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 5, June 2012
268
AFRICA
The results for the sub-sample of individuals who were
aware of their hypertension problem were quite different. In this
logistic regression analysis, only the frequency of doctor visits
was significantly associated with treatment of hypertension
(Table 3).
Among the hypertensives, on multivariate analysis, only
the frequency of doctor visits was associated with control
of hypertension (Table 3). Therefore, people having seen a
doctor during the preceding year more often had controlled
hypertension than those who had not seen a doctor the previous
year. However, among treated individuals, no variable was
associated with control of hypertension (Table 3).
Discussion
The prevalence of hypertension in our population sample
corresponded with that observed among older people in
other sub-Saharan African cities
5-14
or in other developing
countries such as India and Bangladesh.
17
In Dakar,
two out of three people 50 years and older suffered from
arterial hypertension, a disease that has now become a
major public health concern in the Senegalese capital.
In keeping with what has been observed among other
populations, aging and problems of overweight and obesity
were associated with hypertension.
23,24
However, this was not the
case with educational level. This observation seems to indicate
that the Dakar population is currently in an advanced stage of
epidemiological transition. This process is characterised by a
transfer of risk factors for chronic illnesses from the better-
educated individuals in the early stages of the process to the less
educated at the end of the transition.
25
The rate of awareness of hypertension among the hypertensives,
approximately 50%, corresponds with that observed among
the elderly living in other developing countries.
17
This rate is,
however, much lower than that noted in the West, where over
two-thirds of older hypertensives are aware of the problem.
18,19
If the ‘rule of halves’
26
remains valid here, it nevertheless
conceals great disparities, especially between men and women.
As with most developing populations, women were more often
informed on their problem of hypertension than men.
27
However,
the reasons for this association remain poorly understood.
17
In
fact, it may appear surprising in Senegal, where male domination
over women is taken for granted.
28
The Demographics and Health Survey conducted in 2005
indicated for instance that scarcely 12% of married women
made their own decisions about their personal healthcare
spending, whereas for 67% of them, only their spouse made such
decisions.
29
However, in Senegal, it is primarily women who take
care of the health of members of the household, accompanying
their daughters, daughters-in-law and grandchildren to healthcare
institutions. This might explain both their more frequent visits to
these institutions and their greater monitoring of hypertension.
Unlike the results noted for elderly German and American
populations,
18,19
awareness of hypertension rises with age among
the elderly in Dakar. Therefore the probability of having been
identified as hypertensive rises with age. More surprisingly,
we have seen that people with a higher educational level were
often less informed on their hypertension than those with
an average educational level. This result runs contrary to all
research conducted on the subject, which generally demonstrates
the opposite.
30
More research is required to understand this
specificity, but it could be that education does not have the same
implications for health management in Dakar as in developed
countries. Nevertheless, it is not surprising to note that the factor
most strongly associated with awareness of hypertension was the
frequency of doctor visits.
More than 70% of individuals aware of their hypertension
reported taking treatment, which seems well above the rule of
halves. This theoretically encouraging statistic should, however,
be discussed in light of the results associated with control of
hypertension. Fewer than 17% of the people who reported
being treated actually had controlled hypertension, i.e. 6.7% of
hypertensives.
A study conducted in Ghana could help explain why the
hypertension control rate was so low among the elderly in
Dakar. According to this study, 93% of the people treated for
hypertension did not comply with their medical prescriptions,
usually due to the high cost of medication.
31
The same observation
seems to hold true in Dakar where the price of medication is
disproportionate to average expenditure per person per day, i.e.
1 224 FCFA (
≈
2.7 dollars).
32
However, another explanation could be advanced. According
to Salem, treatment of chronic disease is generallymisunderstood.
In Dakar, when a disease is identified, it is believed it should be
ejected as a foreign body.
33
The notion of chronic illness goes
against this conception, which could explain the low level of
compliance with treatment.
Since pharmacological treatment of hypertension is the
consequence of its detection by healthcare personnel, factors
associated with treatment among hypertensives were the same
as those associated with awareness of this health problem, i.e.
frequency of doctor visits, gender and age. Among these factors,
only the frequency of doctor visits was significantly associated
with the control of hypertension. Therefore it was the only factor
investigated that was associated with awareness, treatment and
control of hypertension in this study. This result highlights the
absolute necessity of improving the follow-up health checks of
olderadultstominimisetheconsequencesofhypertensioninDakar.
Strengths and limitations of the study
This research was, to our knowledge, the first study conducted
specifically on hypertension among the elderly in sub-Saharan
Africa. In years to come, the elderly in developing countries will
represent the majority of older people on the planet.
34
Therefore it
is necessary to understand the prevalence of hypertension among
these populations, as well as the rates of awareness, treatment
and control of the disease, in order to combat this burden more
effectively and in a more appropriate manner.
This study has several limitations. As in many studies,
arterial blood pressure was measured twice during a single visit,
which may have led to overestimation of the prevalence of
hypertension. Furthermore, the treatment rate of hypertension
was assessed solely by individual self-reporting. Verification of
the actual presence of medication in the home might have limited
the bias associated with these declarations.
Conclusion
The results of this study have several public health implications.
Firstly, two-thirds of the Dakar elderly suffer from hypertension,
