People who experience significant temperature drops particularly during cold weather are more likely to suffer heart failure and an irregularity in their heartbeats known as atrial fibrillation, a new study says.

Cardiologist Dr. Abhishek Deshmukh and his colleagues at the Mayo Clinic in Minnesota set out to discover the seasonal differences involved strokes and heart attacks. They examined various factors that were present in patients in the United States who were hospitalized because of heart failure and atrial fibrillation.

The team found that hospitalization rates were at their highest during cooler months of the year, particularly in February.

Deshmukh said it was striking that more people become afflicted with various cardiac illnesses during cooler months. He pointed out that more studies should be made in order to find out what factors could trigger such an occurrence.

The new findings provide interesting insights into heart failure and atrial fibrillation, two conditions that have been ailing many people in the United States.

According to the Centers for Disease Control and Prevention (CDC), as many as five million Americans suffer from heart failure each year, while six million are burdened by atrial fibrillation.

For their work, Deshmukh and his colleagues focused on cases where patients were hospitalized because of heart failure from 2002 to 2012. They examined 12 million individuals who fit this description, about a third of whom were also diagnosed with atrial fibrillation.

After averaging the number of times these people were hospitalized throughout and 10-year period, the research team discovered that patients who had heart failure and those who had both atrial fibrillation and heart failure were significantly more likely to be taken to the hospital for their ailments during winter months than during summer months.

While the rate of hospitalizations for these individuals was at its lowest during July, it steadily increases in the following months until it reaches its highest rate in February. By the time February ends, the number of hospitalizations starts to decline until it reaches its lowest point during summer.

The researchers said they have yet to identify the factors involved in such seasonal differences, though Deshmukh may have some ideas as to the "plausible reasons."

He said that the changes could be brought on by an imbalance in the patients' bodily fluids, drastic changes in their hormones, an increase in their infection risk and even the sudden shifts in the air pollution around them.

Deshmukh added that by increasing people's awareness on such seasonal differences, it could lead those who suffer from heart failure and atrial fibrillation to pay closer attention to their symptoms.

Deshmukh and his colleagues are set to present their findings at the Heart Rhythm Society's conference in San Francisco this week.

Photo: Sharon Sinclair | Flickr