In a study conducted across 15 states by 1,233 doctors, it was found that hypertension diagnosis can be off the mark with just one blood pressure test. With 24 per cent people surveyed, it was found that hypertension was misdiagnosed in the first visit to the doctor because the patient had high blood pressure during the test. In contrast, 18 per cent people who actually had hypertension were not diagnosed in the first test.
With the study, doctors suggest at least three blood pressure tests in an interval of two minutes to confirm hypertension or home-based tests during which the patient is relaxed and accurate blood pressure (BP) can be noted.
The study conducted by Eris Lifesciences, a pharmaceutical company headquartered in Ahmedabad, included 18,918 people, aged between 18 to 75 years, across 355 cities in 15 states. Normal blood pressure range is below 140 and above 90. White coat hypertension is a condition in which patients have increased blood pressure when they visit a doctor, but are not really hypertensive. “This happens a lot if a person visits a hospital for first time or has stress while undergoing a test. The BP reading is found to be high. Readings at home will show normal blood pressure,” said Dr C K Ponde, cardiologist at Hinduja hospital. In such cases, hypertension medications may start even if the patient does not need them.
The contrast condition is masked hypertension, where a patient is hypertensive but it does not immediately get diagnosed in first BP reading by a doctor. “What is worrying is masked hypertension. Since these patients are not aware of their condition. They can suffer from heart problems, kidney ailment if the treatment does not start on time,” said cardiologist Brian Pinto, from Holy Family hospital, Bandra.
In Mumbai, where 1,643 people were evaluated, 15.4 per cent people were found to have masked hypertension and 22.8 per cent had white coat hypertension.
“What also surprised us was that in India, unlike other countries, people have higher blood pressure in the evening than in the morning. We don’t understand why,” said principal investigator of study, Dr Upendra Kaul.
The study showed that Rajasthan had the highest white coat hypertension diagnoses at 42.5 per cent, while Bihar had highest masked hypertension at 25.2 per cent.
The study indicates the need for multiple tests before hypertension is confirmed. “In public health system, we usually test thrice for blood pressure before starting hypertension treatment. So, over dosing patients who are not hypertensive does not happen,” said Dr Nikhil Patil, in-charge of non communicable disease in the Directorate of Health Services.
Local health workers, however, claim conducting three tests is time consuming and multiple tests are only done for those who show high BP in their first test.
Maharashtra government data shows 1.4 crore people have been screened since 2018 of which 2.53 lakh were diagnosed with hypertension. According to Dr Yogesh Kalkonde, from NGO Search, who treats hypertension in the tribal district Gadchiroli, the issue of high drop out from treatment and need for increased coverage needs focus. “Countries like Argentina distributed home-based BP machines for trial. In western countries wearable devices to measure BP are picking up the trend. But in India, these trends are yet to set in,” he said.
Doctors said while home-based devices provide correct diagnosis, they need to be calibrated every six months for accuracy. In Gadchiroli, for instance, Kalkonde is using simple a measure to avoid white coat hypertension. He makes his nurse take the BP reading. “A patient gets high BP by just seeing a doctor. They feel more relaxed with a nurse,” he said.
Several pharmaceutical companies are also investing in ambulatory blood pressure monitoring devices to measure BP regularly over 24 hours for accurate reading.