VOLUME 9 NUMBER 3 • SEPTEMBER 2012
109
SA JOURNAL OF DIABETES & VASCULAR DISEASE
REVIEW
is recommended by a number of national and international
guidelines.
4, 10-12
Screening should begin prior to the commencement of treatment
or as soon as is reasonably possible, 2–3 months later to assess the
acute metabolic effects of the antipsychotics and thereafter on an
annual basis unless significant treatment changes are contemplated
(
Table 2). One exception to this timetable is the measurement of
weight, which should be performed weekly during the initial phase
of treatment.
Cardiovascular risk assessment should include a detailed medical
history to assess risk factors, physical examination to include weight
and blood pressure, a blood test to assess lipids and glycaemia and
an ECG.
4
Although waist circumference may provide additional
information, this measurement has proven difficult to achieve in the
UK. While a fasting blood sample is required to interpret a full lipid
profile, there may be merits in taking a pragmatic approach and
accepting a non-fasting sample when logistical difficulties prevent
the patient attending fasted. The sensitivity and specificity for
diabetes, particularly if the glucose measurement is combined with
measurement of glycated haemoglobin (HbA
1
c
),
do not differ greatly
and the 10-year cardiovascular risk assessment employs the total and
HDL cholesterol, which are largely unaffected by eating. Although it
may be easier to obtain a non-fasting sample, clinicians should not
assume that patients with severe mental illness are unable to attend
fasted since several studies have shown that this is feasible.
The latest Quality and Outcomes Framework now includes four
indicators for physical health measurements in the mental health
domain; these are the recording of body mass index (MH12), blood
pressure (MH13), total-to-HDL cholesterol ratio (MH14) and blood
glucose (MH15).
11
Although MH14 and MH15 are only for those over
the age of 40 years, this initiative should improve the monitoring of
cardiovascular risk factors in those with psychotic illness.
Current screening practices
In the National Health Service, where to a large extent care is not
offered unless requested, people with severe mental illness may be
disadvantaged. The Disability Rights Commission has highlighted
that, instead of receiving holistic care, many people with mental
illness describe how their physical illnesses are overshadowed by
the mental illness, with healthcare professionals concentrating
on the latter to the detriment of the former.
13
Consequently,
many people with severe mental illness are not screened for
cardiovascular risk factors. In an audit of 50 in-patients and 50
out-patients of people with severe mental illness in Hampshire,
documented evidence that blood pressure had been measured
was found in only 32% of case notes, while glucose (16%), lipids
Table 2.
Recommended screening based on currently available guidelines
Baseline
2–3
months
Annual
Target
Medical history, to include
✔
✔
✔
family history, ethnicity,
smoking, alcohol, diet,
exercise
Height
✔
Weight
a
✔
Every week during first
✔
BMI < 25 kg/m
2
6–8
weeks of treatment
and at every clinic
visit thereafter but
at least quarterly
Blood pressure
✔
✔
✔
< 140/90 mmHg
Glucose
b
✔
✔
✔
•
Fasting glucose < 6.0 mmol/l
•
Non-fasting glucose < 7.8 mmol/l
Glycated haemoglobin
c
✔
✔
✔
< 6.0% (42 mmol/mol) if no history of
diabetes; target should be individualised
for people with diabetes but likely
6.5–7.5% (47–58
mmol/mol)
Lipid profile
d
✔
✔
✔
•
Total cholesterol < 5.0 mmol/l or
< 4.0 mmol/l
if established CVD or diabetes
•
LDL cholesterol < 3.0 mmol/l or
< 2.0 mmol/l if established CVD or diabetes
• 30%
reduction in patient starting statins
ECG
✔
✔
✔
To assess QTc interval
a
Additional information can be obtained by measuring waist circumference: target in men < 94 cm, in women < 80 cm. Lower values should be sought in people
from non-European descendancy;
b
Either a fasting or non-fasting sample can be used. Fasting samples are more reproducible but may be logistically more difficult to obtain. A formal 75-g OGTT is
needed only rarely;
c
Note HbA
1
c
may be normal in situations where there is a rapid onset of diabetes;
d
Either a fasting or non-fasting sample can be used. Fasting samples are needed to assess LDL cholesterol and triglycerides but cardiovascular risk can be calculated
using total:HDL cholesterol ratio which is largely unaffected by eating. BMI = body mass index; CVD = cardiovascular disease; LDL = low-density lipoprotein;
HbA
1
c
= glycated haemoglobin; OGTT = oral glucose tolerance test; HDL = high-density lipoprotein.
