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VOLUME 12 NUMBER 1 • JULY 2015
RESEARCH ARTICLE
SA JOURNAL OF DIABETES & VASCULAR DISEASE
Patient characteristics and cardiovascular risk profile differed by
ethnic group. A family history of premature CVD was reported by
34% of Caucasian patients while the diabetes prevalence of 25.6%
was the lowest of all the ethnic groups studied. Hypertension
was found in 69.8% and CVD in 41.1% of Caucasian patients.
Black patients were least likely (1.8%) to report a family history of
premature CHD and had the lowest (5.3%) smoking rates.
However, hypertension was almost universal (93.3%) and
diabetes and obesity were highly prevalent at 71.2 and 61.9%,
respectively. Despite the high prevalence of hypertension and
obesity, only 9.7% of black patients had clinically overt CVD. Asian
patients had the highest rates of CVD (51.5%) among all ethnic
groups studied and also the highest reported rate of a family
history of premature CVD (44%). Diabetes was highly prevalent
at 44.4% while the hypertension prevalence of 64.6% was similar
to that observed in Caucasian patients. Mixed-ancestry patients
had the highest smoking rates (18%) while the diabetes and
hypertension prevalences were 50.8 and 89.3%, respectively. CVD
was documented in 49.2% of mixed-ancestry patients.
CVD was almost twice as common in men (49.9%) than
women (26.3%). DM was more common in men than women
(45.7% vs 36.7%), while obesity was more frequent in women
(46.8% compared with 35.7%). Additionally, using the 2011 ESC
criteria, 73.5% of patients (83.9% men and 66.0% of women)
were classified as very high risk for CV complications [defined as
having CVD, DM and/or an ESC systematic coronary risk evaluation
(SCORE) risk of ≥ 10% on chronic statin therapy].
Lipid-modifying regimens and statin potency
Prior to enrollment in DYSIS, patients had been treated with
various lipid-lowering therapies. The most commonly prescribed
statin was simvastatin (64.6%), followed by atorvastatin (22.2%),
rosuvastatin (10.9%), pravastatin (1.6%), fluvastatin (0.6%) and
lovastatin (0.2%). Other lipid-lowering agents were used by only
2% of patients, including ezetimibe (1.2%), fibrates (0.9%) and
bile acid sequestrants (0.2%).
The most frequently used statin dose potency was 3 (equivalent
to 20 mg simvastatin per day) for both very high-risk patients
(40.2%) and non-very high-risk patients (47.6%), while the
second most-frequent dose potency was 2 (equivalent to 10 mg
simvastatin per day) in 32.4 and 25.6% of very high-risk patients
and non-very high-risk patients, respectively (Fig. 1). While statin
dose potency 3 was most frequently used in Caucasian, Asian and
mixed-ethnicity patients, a dose potency of 2 was most common
in black patients.
Lipid abnormalities
Data on the frequency of lipid abnormalities, including sub-analyses
by CVD risk level, are provided in Tables 2 and 3. Among all patients
(
n
= 1,029), 50.3% had LDL-C levels not at goal. We defined ‘not at
LDL-C goal’ as LDL-C ≥ 1.8 mmol/l and LDL-C reduction of < 50%
for patients with CVD, DM and/or a SCORE risk of ≥ 10% (very high
risk), and as ≥ 2.5 mmol/l and ≥ 3 mmol/l for patients with a SCORE
risk of 5 to 9% (high risk) and 1 to 4% (moderate risk), respectively.
Elevated TG levels (defined as > 1.7 mmol/l) were seen in 45.3% of
patients, and 33.7% had low HDL-C levels (defined as < 1.0 mmol/l
for men and < 1.2 mmol/l for women).
The most prevalent lipid disorder (either alone or in combination)
in very high-risk patients was above-target LDL-C levels (60.1%),
followed by elevated TG levels (45.8%), and low HDL-C levels
(36.0%). By contrast, in both high- and moderate-risk patients,
elevated TG levels were observed more frequently (46.7 and 40.1%,
respectively in the two risk groups) than above-target LDL-C levels
(33.3 and 24.1%, respectively) and low HDL-C levels (25.0 and
26.3% for both risk groups, respectively).
We next performed a sub-analysis of lipid abnormalities for
only very high-risk patients (756 of all patients, Table 3), which
we stratified as indicated. Of those with CVD and DM, 57.9%
Table 2.
Lipid abnormalities according to ESC guidelines (2011) on risk stratification
All patients
(
n
= 1 029)
Very high risk*
(
n
= 756)
High risk
(
n
= 92)
Moderate risk
(
n
= 139)
Low risk
(
n
= 42)
LDL-C not at target (%)
†+
50.3
60.1
33.3
24.1
Low HDL-C [< 1.0 (men)/1.2 (women) mmol/l) (%)
‡
33.7
36.0
25.0
26.3
34.1
Elevated TG (> 1.7 mmol/l) (%)
§
45.3
45.8
46.7
40.1
50.0
*Very high risk = CVD, diabetes, and/or SCORE risk ≥ 10% (chronic kidney disease was not documented in DYSIS)
†
LDL-C ≥ 3.0 mmol/l in patients with SCORE risk 1–4%, LDL-C ≥ 2.5 mmol/l in patients with SCORE risk 5–9%, LDL-C ≥ 1.8 mmol/l in patients with CVD, DM,
and/or SCORE risk ≥ 10%; LDL-C ≥ 1.8 mmol/l
+
Data on 987 patients were available
‡
Data on 1 025 patients were available
§
Data on 1 027 patients were available
In the ESC 2011 guidelines, no LDL-C goal was specified for the low-risk group.
Table 3.
Lipid abnormalities according to ESC guidelines (2011) in very high-risk patients
CVD + DM
(
n
= 131)
CVD (w/o DM)
(
n
= 241)
DM (w/o CVD)
(
n
= 285)
SCORE ≥ 10%
(
n
= 99)
LDL-C ≥ 1.8 mmol/l and LDL-C reduction < 50% (%)*
57.9
68.0
53.8
61.9
Low HDL-C [< 1.0 (men)/1.2 (women) mmol/l] (%)
†
39.7
33.8
37.9
31.3
Elevated TG (> 1.7 mmol/l) (%)
‡
54.2
38.2
51.9
35.4
*Data on 722 of a total of 756 high-risk patients were available
†
Data on 755 patients were available
‡
Data on 756 patients were available.