Description

The combination of systemic hypertension and glucose
intolerance carries more pathological consequences for the
arteries and the internal organs than either of the conditions
alone. Recent reports have identified a high prevalence of
previously-unrecognised glucose intolerance in subjects with
systemic hypertension. In view of this, it is necessary to
actively seek out occult diabetes mellitus and impaired
glucose intolerance (IGT) in patients with systemic
hypertension in order to be in a position to implement
appropriate management strategies and avoid unnecessary
complications. Unfortunately, there is little consensus as to
the best measure of diagnosing glucose intolerance. Using the
fasting plasma glucose level and/or HbA1c to diagnose
glucose intolerance in patients with systemic hypertension is
insufficient not only because of its low sensitivity to diagnose
diabetes, but also due to its inability to identify IGT. The
oral glucose tolerance test (GTT) is the most accurate
currently available test for diagnosing abnormal glucose
metabolism. For cost reasons GTT is not widely used for
general screening purposes and for the same reason, hospitals
often limit its use to patients with a glucose level above
6.0mmol/l.

Failure to identify abnormalities of glucose tolerance
results in serious underestimation of the cardiovascular risk of
these patients and denies patients primary preventative
measures, which are based on risk assessment. Because of the
high prevalence of IGT in hypertensive patients, we believe
that all patients referred to Hypertension Clinics who are
deemed to need treatment for raised blood pressure should be
investigated by GTT. This strategy is vitally important not
only to determine the target blood pressure but also to enable
appropriate management strategies to be put in place in order
to prevent further progression to diabetes.