The disorder that killed Leonard Nimoy, the actor best known for his role as Mr. Spock on Star Trek, was chronic obstructive pulmonary disease (COPD), a progressive illness often linked to smoking. He died at his home on February 27 at the age of 83. He was one of the roughly 15 million Americans diagnosed with the disorder.
But just what is COPD? That umbrella term refers to a group of diseases that cause airflow blockage and breathing-difficulties, including emphysema and chronic bronchitis. In the U.S. COPD most often stems from exposure to tobacco smoke. (Last year Nimoy tweeted to fans that he quit smoking three decades ago.) Genetic factors, respiratory infections and air pollutant exposures, however, can also play a role. It’s a leading cause of death in the U.S., with symptoms that include shortness of breath, wheezing, chronic coughing and excess production of mucus in the airway. The disease is typically diagnosed with a simple breathing test called spirometry, which assesses how much air a person can inhale and exhale. And although medications can help patients improve their breathing by dilating their air passages, the malady has no cure.
It’s also a massive global problem. In 2012, 6 percent of all mortality worldwide was attributed to COPD—equivalent to more than three million deaths. More than 90 percent of those deaths occurred in low- or middle-income countries, according to the World Health Organization. In settings where families may cook over traditional cookstoves that rely on solid fuels (including burning feces), such harmful exposure and subsequent poor air quality is a significant contributor to COPD. And globally, the disease now develops among men and women in equal numbers.
Pres. Barack Obama, who once greeted Nimoy with the signature Vulcan salute, wrote in a press statement on the actor’s death, “I loved Spock.” Many people around the world could say the same.

Credit: CDC