Patients should be screened for hypertension, hyperlipidaemia, diabetes and a smoking history should be taken. Any cardiovascular risk factors should be aggressively managed.
Low risk patients (aged under 40 years with no high risk features)
Receive aspirin alone. There is evidence that in patients under the age of 40 years the complication rate is only one quarter of that seen in patients aged 40 - 59 years.
Intermediate risk patients (aged 40 to 59 years with no high risk features)
Usually are treated with either aspirin or aspirin and hydroxycarbamide.
High risk patients
Receive aspirin and hydroxycarbamide
The target platelet count for those receiving cytoreductive therapies is 200-400x109/l.
Pregnancy in PT requires careful management. In general low risk patients should continue aspirin and be closely monitored by a haematologist and obstetrician. Patients being treated with hydroxycarbamide should use adequate contraception. For patients of either sex contemplating pregnancy hydroxycarbamide should be interrupted for 3-6 months beforehand and interferon alpha substituted when a cytoreductive drug is considered necessary.