Dr's Casebook: Keep warm at home to lower risk of high blood pressure
It is Halloween this Sunday and the clocks are due to go back.
That means longer nights as winter approaches.
As the temperature drops it will be necessary to keep the home warm. Some people are quite stoical about this and are happy to put up with cold living rooms.
However, recent research has shown it is sensible to keep the rooms warm to help keep blood pressure down.
Blood pressure is recorded as two numbers.
Firstly, the systolic pressure, which represents the pressure attained as the heart beats to pump blood round the circulation.
Secondly, the diastolic pressure, which represents the pressure in the circulation as the heart relaxes between beats.
The measurement is written with the systolic figure on top and the diastolic number on the bottom, thus 120/80. These numbers each represent the recorded pressure in mmHg. This means mm of mercury, which is the standard means of measuring pressure.
People often assume that headaches will be the first symptom of hypertension but more often than not, it is a totally symptomless condition.
The only way you can find out if you have it is by having your blood pressure measured.
Past research has linked colder living conditions with raised blood pressure.
However, these were small studies. Recent research included data from the Health Survey of England in 2014, which included information from more than four and a half thousand people aged 16 years and over.
Initially, each person completed a questionnaire about lifestyle. They were then visited by a nurse and had blood pressures taken and the temperature of their living rooms measured.
They found that for every degree decrease in temperature, there was an increase of 0.5 mm in both systolic and diastolic blood pressure. People in the coldest homes had on average five millimetres higher systolic and diastolic pressures.
Interestingly, the relationship between indoor temperature and blood pressure was most marked in the participants who did not exercise regularly.
That can be very significant and the researchers say this can help explain the higher rates of hypertension as well as potential increases in deaths from strokes and heart disease during the winter months.
Although they could not give a perfect temperature, they suggest that 21 degrees Celsius is the minimum advisable.