Cardiovascular Journal of Africa: Vol 30 No 3 (May/June 2019)

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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 30, No 3, May/June 2019 172 AFRICA
to warfarin for non-valvular AF, these drugs were prescribed
in only 4.4% of these patients. Availability of these drugs in
public health facilities in Botswana (and possibly in other SSA
countries) is limited by their high cost and probably the absence
of antidotes. The drugs remain an option for only a select
group of individuals in private health facilities. For the same
cost-related reasons, beta-blockers and digoxin were the only
prescribed rate-controlling medications. Similar observations
were made in Cameroun where digoxin and beta-blockers were
the main anti-arrhythmic drugs used.24
In the present study, the overall mortality rate at 12 months
(14.5%) was higher than previously reported in a similar study in
Kenya (10%).26 It was much higher than the 24-month mortality
rate (3.8%) observed in a large European study.8 A much higher
12-month mortality rate (29.5%) has, however, been reported in
an African study.24
The reasons for the higher mortality rates in our cohort and
other SSA countries than in Europe may include variation in
the study settings, management and control of co-morbidities,
quality of anticoagulation control, and in the treatment of
AF.7 The present study was conducted in a tertiary hospital
where complex and very ill cases are more likely to be referred,
and hence the high mortality rate. Although the use of oral
anticoagulants was high in our patients, a recent report from
Botswana showed suboptimal anticoagulation control among
patients on anticoagulation.35 The high burden of RHD among
our patients could also have contributed to an increased risk
of mortality in our cohort, as this subgroup of AF patients is
known to have high mortality rates.
Our study had some limitations. It was conducted in a tertiary
hospital, limiting the generalisability of the findings to other
settings in the country where facilities and expertise are limited.
A selection bias is possible as patients in a tertiary healthcare
facility are more likely to be more ill than those who are managed
at primary or secondary level healthcare facilities. This may
have, in part, contributed to the high mortality rate observed
in the present study. The size of the sample and the duration of
follow up did not allow for the assessment of the determinants
of mortality among our patients.
Although we demonstrated a high usee of anticoagulation,
we have insufficient data to comment on whether the mortality
rate of AF patients was altered by the level of anticoagulation
control, as suggested by others. However, a recent study has
reported poor anticoagulation control in the same setting.35
Therefore, we believe that despite the high prescription of
anticoagulation, poor anticoagulation control may have had
some influence on the observed high mortality rate. Data on
the causes of death were difficult to ascertain, as some patients
died outside the hospital and autopsies were not performed. We
therefore reported on all-cause mortality in our patients.
Conclusion
AF is a common arrhythmia that presents in patients with
hypertension, RHD and heart failure in our setting. The disease
presents in young people and confers a high mortality rate that
is comparable to other SSA countries. In light of the high death
rate associated with AF in our young cohort, additional research
is needed to address the prevention and optimal management of
AF and associated co-morbidities.
We thank the patients and nursing staff of the medical department for their
assistance with the study.
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