CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 5, June 2012
AFRICA
285
the post-thrombolytic era: clinical meaning and value.
Clin Cardiol
1997;
20
(4): 327–331.
16. Mantel N, Haenszel W. Statistical aspects of the analysis of data
from retrospective studies of disease.
J Natl Cancer Inst
1959;
22
(4):
719–748.
17. DerSimonian R, Laird N. Meta-analysis in clinical trials.
Control Clin
Trials
1986;
7
(3): 177–188.
18. Stroup DF, Berlin JA, Morton SC, Olkin I, Williamson GD, Rennie
D,
et al
. Meta-analysis of observational studies in epidemiology: A
proposal for reporting.
J Am Med Assoc
2000;
283
(15): 2008–2012.
19. Reuter H, Burgess LJ, Louw VJ, Doubell AF. The management
of tuberculous pericardial effusion: experience in 233 consecutive
patients.
Cardiovasc J South Afr
2007;
18
(1): 20–25.
20. George S, Salama AL, Uthaman B, Cherian G. Echocardiography in
differentiating tuberculous from chronic idiopathic pericardial effusion.
Heart
2004;
90
(11): 1338–1339.
21. Nugue O, Millaire A, Porte H, de Groote P, Guimier P, Wurtz A,
et al
.
Pericardioscopy in the etiologic diagnosis of pericardial effusion in 141
consecutive patients.
Circulation
1996;
94
(7): 1635–1641.
22. Tsang TS, Barnes ME, Gersh BJ, Bailey KR, Seward JB. Outcomes of
clinically significant idiopathic pericardial effusion requiring interven-
tion.
Am J Cardiol
2003;
91
(6): 704–707.
23. Mayosi BM, Wiysonge CS, Ntsekhe M, Volmink JA, Gumedze F,
Maartens G,
et al
. Clinical characteristics and initial management of
patients with tuberculous pericarditis in the HIV era: the Investigation
of the Management of Pericarditis in Africa (IMPI Africa) registry.
BMC Infect Dis 2006;
6
: 2.
24. Mayosi BM, Wiysonge CS, Ntsekhe M, Gumedze F, Volmink JA,
Maartens G,
et al
. Mortality in patients treated for tuberculous pericar-
ditis in sub-Saharan Africa.
S Afr Med J
2008;
98
(1): 36–40.
Letter to the Editor
Comment on: A systematic overview of prospective
cohort studies of cardiovascular disease in
sub-Saharan Africa
Dear Sir
It was with interest that I read the article titled ‘A systematic
overview of prospective cohort studies of cardiovascular disease
in sub-Saharan Africa’ by André Pascal Kengne,
et al
., which
was published recently in this journal. In this excellent article,
the author introduced the association between cardiovascular
diseases and related risk factors by performing a systematic
review. However, we feel the article did not cover all aspects
of the relationship between cardiovascular disease and related
risk factors.
Firstly, habits may be very different among different ethnic
groups, which is obvious in China, consisting of 56 ethnicities.
This would have affected the outcome of the study,
1
and it would
have been better if there had been further subgroup analysis.
2
Secondly, socio-economic status
3,4
may be different in
different regions in sub-Saharan Africa. Many studies may have
come from different levels of hospitals, such as community and
central hospitals, which also means that the available medical
interventions may have been different.
5,6
Thirdly, it is evident that that the study did not include all
cardiovascular risk factors.
7-9
There was no classification of the
selected risk factors.
10
All of these factors may increase the differences between
the studies and affect the results to a certain extent. There is
undoubtedly a need for well-designed, prospective, cohort
studies from sub-Saharan Africa to clarify these issues.
Zhen-Hua Gao
Ru-Yu Yuan,
Department of Cardiology, Second Hospital of Tianjin Medical
University, Tianjin, People’s Republic of China
References
1.
Detrano R, Guerci AD, Carr JJ,
et al.
Coronary calcium as a predictor
of coronary events in four racial or ethnic groups
N Engl J Med
2008;
358
(13): 1336–1345.
2.
Mcclelland RL, Chung H, Detrano R,
et al.
Distribution of coronary
artery calcium by race, gender, and age: results from the Multi-Ethnic
Study of Atherosclerosis (MESA).
Circulation
2006;
113
(1): 30–37.
3.
Braveman PA, Cubbin C, Egerter S,
et al.
Socioeconomic status
in health research: one size does not fit all.
J Am Med Assoc
2005;
294
(22): 2879–2888.
4.
Lawlor DA, Davey SG, Patel R,
et al.
Life-course socioeconomic posi-
tion, area deprivation, and coronary heart disease: findings from the
British Women’s Heart and Health Study.
Am J Public Health
2005;
95
(1): 91–97.
5.
Law MR, Morris JK, Wald NJ. Use of blood pressure lowering drugs
in the prevention of cardiovascular disease: meta-analysis of 147
randomised trials in the context of expectations from prospective epide-
miological studies.
Br Med J
2009;
338
: 1665.
6.
Vorster HH, Kruger A, Venter CS,
et al
. Cardiovascular disease risk
factors and socio-economic position of Africans in transition: the
THUSA study.
Cardiovasc J Afr
2007;
18
(5): 282–289.
7.
Steyn K, Sliwa K, Hawken S,
et al.
Risk factors associated with
myocardial infarction in Africa: the INTERHEART Africa study.
Circulation
2005;
112
(23): 3554–3561.
8.
Kaptein KI, de Jonge P, van den Brink RH,
et al
. Course of depressive
symptoms after myocardial infarction and cardiac prognosis: a latent
class analysis.
Psychosom Med
2006;
68
(5): 662–668.
9.
Zatu MC, van Rooyen JM, Schutte AE. Smoking and vascular dysfunc-
tion in Africans and Caucasians from South Africa.
Cardiovasc J Afr
2011;
22
(1): 18–24.
10. Erbel R, Mohlenkamp S, Moebus S,
et al
. Coronary risk stratification,
discrimination, and reclassification improvement based on quantifica-
tion of subclinical coronary atherosclerosis: the Heinz Nixdorf Recall
study.
J Am Coll Cardiol
2010;
56
(17): 1397–1406.
