In the United States today, one of every 400 African-American children and one in every 1,250 Hispanic children are born with sickle cell disease, a debilitating, painful condition.

Patients with sickle cell disease suffer from abnormally shaped, rigid and adhesive red blood cells. These abnormal cells "close off" blood vessels and cause recurring, painful episodes called "sickle cell crises."

An individual with sickle cell disease can develop a crisis at any time – the pain can last for days or even weeks and is frequently severe enough to require hospitalization.

These painful events associated with SCD can be more severe and occur more frequently in cold weather.

I saw Robert – a bright-eyed, energetic, 13-year-old boy with SCD – in my office a day after his mother took him ice skating. He had been begging her to go skating, and told me he had a wonderful time and that they spent two hours at the ice rink. He came home tired and sore but very content.

Unfortunately, he woke up in severe pain the next morning and needed to take strong pain medication. He stayed home from school for several days, and the pain returned after he went back to school, requiring hospitalization so he could receive pain medicine intravenously. Robert had not had a pain crisis in the prior two years.

This is not an unusual story. Often times, a patient whose disease has been well-controlled will experience an exacerbation, or crises, after exposure to certain triggers, including extreme weather. For Robert, we discussed several other winter activities he might enjoy just as much as skating that wouldn't trigger a painful crisis.

Medical studies evaluating the impact of cold exposure on SCD don't present a clear picture, partly because hot weather and dehydration are also known triggers for pain crises, and in developed countries the effect of weather is countered by our ability to control the temperature indoors.

However, anecdotally, people with SCD frequently and often consistently report acute pain after exposure to cold, usually within hours. Further analyses from landmark research demonstrates an association between pain severity and cold weather.

Cold weather causes narrowing of blood vessels in the skin, hands, feet, nose and ears. This response as well as cold sensitivity is greatly exaggerated in SCD, as shown in carefully designed experimental studies. Multiple well-conducted studies reveal an association between the onset of pain crises and increased wind speed, which cools the skin.

This effect is exaggerated if the skin is wet, so it's important to stay warm and dry. People also tend not to drink as much water in the winter. The stress, excitement and bustle of the holiday season can unfortunately cause increased adhesion of the red cells, which can then cause a pain crisis.

Finally, viral infections, flu-like illnesses and strep throat are more common in the winter, creating a perfect storm.

SCD can be extremely variable. Some patients are able to participate in winter activities, in which case, I advise them to do so in short intervals of 20 to 30 minutes with periods of rest and hydration in between. Regardless, if you or a loved one has SCD, take note of the following simple steps as the temperature drops to stay healthy and pain-free.

Do:

Dress warmly but in layers and carry an extra pair of dry socks.

Stay hydrated (hot cocoa or herbal teas can be great).

Carry and use a hand sanitizer frequently.

Consider shopping online.

Minimize continuous exposure to cold and windy weather or wet snow.

Get plenty of rest and sleep, minimize stress, know your body and your limits.

Make sure you have pain medications handy to start early in the event of a pain crisis.

Don't:

Forget your hat, gloves and scarf when you step out.

Visit with people who have a cold or febrile illness, if possible.

Drink too much coffee or caffeinated tea, since it can contribute to dehydration.

Get carried away with the ice skating, sledding or building a snowman.

Remember, being practical about guarding against the combination of cold and wet weather can go a long way in preventing a sickle cell crisis during the winter months.