Cardiovascular Journal of Africa: Vol 26 No 2 Supplement (March/April 2015)

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AFRICA S13
CVJAFRICA • Volume 26, No 2, H3Africa Supplement, March/April 2015
national average. While the prevalence of diabetes in the FDRs
in this study was significantly higher than the national average,
8.7 vs 2.3%,28 the prevalence of hypertension in FDRs in the
study was similar to the national average values.29
The high prevalence of obesity among the FDRs of patients
with CKD is another important CVD risk factor that deserves
attention. Some communities in sub-Saharan Africa regard
being overweight or obese as a sign of affluence,30 and so a lot of
people are motivated to gain weight. The contribution of obesity
to cardiovascular morbidity and mortality is significant22 and
with the epidemiological transition taking place in sub-Saharan
Africa, strategies to reduce the burden of obesity are urgently
needed.
Of particular concern is the high prevalence of dyslipidaemia
found in this study. Although the prevalence of dyslipidaemia
was significantly higher in the FDRs of patients with CKD,
the prevalence of more than 60% found in the control arm of
the study suggests that this risk factor for CVD, which is not
frequently assessed in resource-poor settings because of cost,
may be a more serious problem than previously anticipated.
The higher prevalence of albuminuria and reduced eGFR
observed in the FDRs in this study was in keeping with findings
from similar studies.11-15 The higher prevalence of CVD risk
factors among the FDRs of patients with CKD in this population
has highlighted the need to consider this population as having an
increased risk of experiencing adverse cardiovascular events, and
there is a need for targeted interventions.
Our study had some limitations, including the fact that it was
a cross-sectional survey, which has its own inherent weakness,
such as difficulty in interpreting associations between outcome
and exposure, and lack of long-term monitoring. Also, a history
of hypertension and diabetes were self-reported, which may be
subject to recall bias.
Conclusion
In this sub-Saharan African population, risk factors for CVD
were more prevalent in the FDRs of patients with CKD than in
healthy controls.
The authors thank Mr Anthony Amaechi who carried out the laboratory
analyses of the blood and urine samples.
References
1. World Health Organization, 2009. Cardiovascular Diseases.
. Accessed Dec 20, 2014.
2. World Health Organization 2005. Preventing chronic diseases: a vital
investment.
e
3. Gaziano TA. Economic burden and the cost-effectiveness of treatment
of cardiovascular disease in Africa. Heart 2008; 94(2): 140–144.
4. Lopez AD, Mathers CD, Ezzati M, Jamison DT, Murray CJ. Global and
regional burden of disease and risk factors, 2001: systematic analysis of
population health data. Lancet 2006; 367(9524): 1747–1757.
5. Mathers CD, Loncar D. Projections of global mortality and burden of
disease from 2002 to 2030. PLoS Med 2006; 3(11): e442.
6. , , , ,
et al. Level of kidney function as a risk factor for cardiovascular
Table 1. Comparison of measured clinical and laboratory parameters of
the FDRs of patients with chronic kidney disease and the controls
Variables
FDRs
(n = 230)
Controls
(n = 230) p-value
Mean age (years) 33.49 ± 12.0 33.67 ± 12.2 0.87
Mean SBP (mmHg) 116.5 ± 22.5 112.1 ± 18.1 0.02*
Mean DBP (mmHg) 74.9 ± 12.7 71.4 ± 10.5 0.01*
Mean BMI (kg/m2 ) 25.5 ± 5.3 23.8 ± 4.0 0.01*
Mean WC (cm) 81.8 ± 13.3 79.3 ± 11.3 0.03*
Mean HC (cm) 100.0 ± 11.3 98.4 ± 11.5 0.13
Mean SCr (µmol/l) 89.9 ± 23.4 88.3 ± 21.1 0.42
Mean FPG (mmol/l) 4.3 ± 1.1 4.3 ± 0.9 0.79
Mean SUA (µmol/l) 239.9 ± 99.4 237.4 ± 81.3 0.85
Mean TC (mg/dl) 146.5 ± 51.0 147.8 ± 40.1 0.24
(mmol/l) (3.79 ± 1.32) (3.83 ± 1.04)
Mean HDL-C (mg/dl) 30.8 ± 10.5 34.7 ± 12.6 0.10
(mmol/l) (0.8 ± 0.27) (0.9 ± 0.33)
Mean LDL-C (mg/dl) 106.7 ± 42.3 107 ± 38.2 0.41
(mmol/l) (2.76 ± 1.10) (2.77 ± 0.99)
Mean TG (mg/dl) 95.1 ± 22.8 92.3 ± 24.3 0.06
(mmol/l) (1.07 ± 0.26) (1.04 ± 0.27)
Mean eGFR (ml/min/1.73 m2 ) 106.6 ± 28.3 102.3 ± 25.0 0.09
Mean urine ACR 22.1 (0.5–1.406) 18.2 (0.6–1.296) 0.02*
ACR, albumin:creatinine ratio; BMI, body mass index; DBP, diastolic blood
pressure; eGFR, estimated glomerular filtration rate; FDRs, first-degree rela-
tives of patient with chronic kidney disease; FPG, fasting plasma glucose; HC,
hip circumference; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-
density lipoprotein cholesterol; SCr, serum creatinine; SUA, serum uric acid; TG,
triglyceride; WC, waist circumference.
Table 2. A comparison of the frequency of risk factors for
cardiovascular disease among the FDRs of patients with
chronic kidney disease and the controls
CVD risk factors
FDRs
(n = 230)
n (%)
Controls
(n = 230)
n (%)
Odds
ratio 95% CI p-value
Presence of hypertension 56 (24.3) 29 (12.6) 2.23 1.33–3.76 0.01*
Presence of diabetes 20 (8.7) 6 (2.6) 3.56 1.32–10.10 0.01*
Presence of obesity 40 (17.4) 23 (10.0) 1.89 1.06–3.40 0.02*
Significant history of
cigarette smoking
14 (6.1) 6 (6.2) 2.42 0.85–7.20 0.07
Presence of truncal obesity 46 (20.0) 39 (17.0) 1.22 0.74–2.02 0.40
Significant history of
alcohol use
58 (25.2) 41 (17.8) 1.55 0.97–2.50 0.05
Presence of hyperuricaemia 14 (6.1) 4 (1.7) 3.66 1.10– 3.39 0.02*
Presence of dyslipidaemia 171 (74.3) 138 (60.0) 1.93 1.28–2.93 0.01*
Presence of reduced eGFR 13 (5.7) 4 (1.7) 3.38 1.01–12.50 0.03*
Presence of albuminuria 85 (37.0) 51 (22.2) 2.06 1.34–3.17 0.01*
CI, confidence interval; CVD, cardiovascular disease; FDRs, first-degree relatives
of patients with chronic kidney disease; eGFR, estimated glomerular filtration
rate. Moderate alcohol drinking was defined as consumption of one drink (14 g)
per day. Moderate-to-heavy cigarette smoking was defined as smoking at least six
cigarettes per day.
Table 3. Logistic regression of cardiovascular risk factors among
FDRs of patients with chronic kidney disease
CVD risk factors Odds ratio 95% CI z-statistic p-value
Presence of hypertension 1.65 1.05–2.84 1.82 0.04*
Presence of diabetes 2.37 0.89–0.50 1.72 0.08
Presence of hyperuricaemia 2.76 0.86–8.84 1.71 0.09
Presence of dyslipidaemia 1.73 1.15–2.60 2.62 0.01*
Presence of reduced eGFR 2.12 0.64–6.99 1.23 0.21
Presence of albuminuria 1.62 1.05–2.50 2.17 0.03*
FDRs, first-degree relatives; CI, confidence interval; CVD, cardiovascular
disease; eGFR, estimated glomerular filtration rate.