The weather is getting colder. The days are shorter. People leave for work in the dark and come home in the dark. Winter is here and with it comes an increase in heart disease and heart related deaths. There are many reasons why winter weather worsens heart problems. Heart patients are under more stress at the extremes of temperatures. Cold weather increases the workload on the heart. For example, it is harder to walk in 20 degrees with a biting wind than on a calm 70-degree day. The cold may cause the heart arteries to spasm, reducing the blood flow to the heart resulting in chest pain or a heart attack. Wintertime brings an increase in flu and pneumonia. These respiratory infections put a significant strain on the heart and are the reason why the flu vaccine is recommended for all heart patients. Another factor may be the colorfully named winter blues, or Seasonal Affective Disorder.
Seasonal affective disorder (SAD) is a type of depression triggered by the shorter days in winter. The depression eases during the summer months. It is felt that shorter amounts of sunlight cause a chemical change in the brain. Melatonin, a hormone which is made when it is dark to aid in sleep, may also be involved. In the winter, people continue to make melatonin later in the day, as dawn comes later. The melatonin can cause daytime sleepiness and fatigue. In addition to a sleepy feeling and fatigue, SAD causes loss of interest in activities formerly enjoyed, social withdrawal, irritability, anxiety, decreased ability to focus and physical problems such as chest pain. SAD is different from major depression in that it causes people to eat more and gain weight. Patients with major depression have difficulty sleeping, a decreased appetite and weight loss. SAD is treated with light therapy, either getting more sunlight or sitting in front of a light box. Psychotherapy and antidepressants are also used. In addition, patients with SAD should make an effort to be more social, exercise regularly, and avoid alcohol as it can make depression worse.
The relationship between depression and heart disease has mostly been studied in patients with major depression, but it likely applies to SAD patients as well. It has long been known that depression can lead to heart disease. Depression can decrease immunity and promote inflammation, conditions that can lead to plaque formation in heart arteries. In addition, depression increases certain hormones (catecholamines) which raise the blood pressure and heart rate, leading to heart disease. Lastly, depression is associated with poor lifestyle behaviors such as being sedentary, eating the wrong foods, smoking or alcohol use and not taking prescribed medications. On the other hand, patients with heart disease are prone to develop depression. After a heart attack, patients who become depressed are three times more likely to die than patients who do not have depression. After open-heart surgery depression is quite common and is associated with worse outcomes.
The winter blues can manifest not only psychologically, but also physically. The other winter blue happens when extremities turn blue in cold weather. This is called Raynaud’s Phenomenon. Raynaud’s typically affects the fingers, toes and the tips of the nose and ears. It occurs when a trigger (cold or emotional stress) causes extreme spasm of the blood vessels to the extremity. The blood flow is cut off causing the affected part to first turn white, then blue. Often there is pain associated with the color changes. After about 15 to 20 minutes, the spasm subsides, the extremity turns bright red and there is a burning sensation as the blood flow returns. Raynaud’s has two forms, a primary one where the cause is unknown and a secondary form which is due to another disease (for example lupus or scleroderma). The primary form occurs in about 4% of the population, is seen more with women than men and usually starts at a young age (15-30 years old). The main treatment is avoidance of the cold and warming. Local warming is with gloves or thick socks; systemic warming involves keeping the whole body warm with layers of clothing. In extreme cases, medications can be prescribed, such as calcium channel blockers or vasodilators.
Whether your winter blues are physical or emotional, one should make an effort to follow lifestyle behaviors that can help either condition. This includes regular exercise, as exercise is known to reduce depression. In addition, exercise causes the small arteries in the hands and feet to dilate, increasing the blood flow to those areas. Smoking should be avoided as it worsens depression and causes the small arteries to spasm. Staying warm by snuggling under a blanket in front of a roaring fire is not a bad option for either of the winter blues.