Cold weather could lead to upsurge in heart attacks and strokes
There is an increased risk of heart attack and stroke in the days immediately after a cold snap, NHS England has warned.
As temperatures plummet below freezing across much of the country, the number of people being admitted to A&E is also likely to increase, the public body said.
With much of Britain gripped by chilly conditions, NHS England said that heart attacks increase almost immediately after a cold snap, accounting for two in five winter excess deaths.
Hospitals also see a rise in the admission of stroke patients five days after the cold weather begins and peak respiratory admissions go up 12 days after the temperature drops.
For every one degree that the temperature drops below 5C there is a 10% rise in elderly people presenting with breathing problems and almost a 1% increase in emergency admissions, NHS England said.
Keith Willett the national director for acute care at NHS England said most people are "unaware" of the immediate knock-on-effect of cold weather on health.
"Patients who have pre-existing conditions may not be aware that they are most at risk of falling ill in the days after temperatures drop," he said.
"This also adds pressure on already busy A&E departments and can be avoided by taking simple steps to keep well.
"Those with pre-existing heart and lung conditions and particularly the elderly should take care to keep their homes properly heated and get their flu jabs.
"We are also asking the public to keep an eye on any elderly neighbours they might have who are the most vulnerable during the winter months."
The number of emergency admissions is also linked to colder weather circulating viral infections, including the flu.
Older people who may be frail, or who have existing health conditions, are particularly at risk, NHS England said.
Last winter there were 400,000 additional A&E attendances, bringing the total to more than 7.5 million, an increase of 5.6% on the previous year, the body said.