The Whys and Wherefore’s of White-Coat Hypertension

Yesterday was Mother’s Day for our readers who live in the US.  I do, but my mother doesn’t, so rather than treat her to lunch or chocolate, I’m dedicating this blog to her instead.

Let me start by saying that hypertension runs in our family.  My grandmother and her mother before her had it, my mother has it and even though I was an ultra-fit marathon runner at the time, I also developed high blood pressure around the time I turned 40.

But that’s where the family trait ends. We manage our disease very differently.  I take my meds, try to eat healthily, avoid stress and exercise whenever I can. I also avoid taking my blood pressure.  If I don’t know it’s high, it’s one less thing I have to worry about!  My mom, on the other hand is a much more compliant patient and goes for regular check-ups.

The problem with that, is she worries so much about having her blood pressure taken that it’s always high when she sees her doctor.  She can’t explain why she worries about this, she knows it’s not rational, but still she worries.  And she’s not alone.

For many patients, blood pressure measurements taken in a physician’s office may not correctly characterize their typical blood pressure. Up to 25% of patients evaluated by their doctors, have blood pressure measurements higher than their typical levels. This phenomena is known as white-coat hypertension and is thought to result from anxiety related to examination by a health care professional.

So I was really interested to read a new study from the UK where, incidentally, my mom lives.  It showed that by swapping a doctor for a nurse you can eradicate white-coat hypertension.

The meta-analysis of 14 studies found that mean blood pressures measured by nurses were 8.5/4.2mmHg lower than readings from doctors. When studies with a high risk of bias were removed from the analysis, the gap was reduced but remained, with a mean difference of 4.8mmHg in systolic blood pressure (the top number) and 1.5mmHg for diastolic (the bottom number).

The study concluded that blood pressure measurements taken by primary care doctors might be ‘unreliable for clinical decisions’, and that all measurements should be delegated to nurses.

Study leader Dr Chris Clark, clinical academic fellow at the Peninsula Medical School and a GP in Witheridge, Devon, said: “The difference could affect treatment decisions, especially when the measurement is marginal, between one course of treatment and another.”

Such a recommendation also has wide-ranging implications for how medical practices organize their services.  Researchers told the European Society of Hypertension Congress that the findings meant practices should move to nurse-only or home blood pressure monitoring.

The rationale for the different blood pressure values obtained by doctors and nurses?  The researchers speculate that nurses are better at relaxing patients.

Would you be more relaxed seeing a nurse rather than a doctor?  My mom says yes!