Parkinson’s cases expected to increase

The numbers of people growing old and living longer have led to ominous projections for Parkinson’s disease. By 2030, there might be 80 percent more Americans with the disease, and the numbers will double in developing Asian nations, according to a new study.

Dr. E. Ray Dorsey and his colleagues at the University of Rochester say the prevalence will grow as populations shift in age. In 2005, an estimated 4.1 million people worldwide had Parkinson’s disease. In 25 years, that number is predicted to climb to 8.7 million.

“This is a chronic condition that will be claiming more and more people,” said Dorsey, co-author of the study published this month in the journal Neurology. The scientists said the growth will be greater outside the United States. China and India have growth curves that are more like a triangle, with more young people than older ones.

“Not only will more people develop Parkinson’s but patients will have it longer and remain disabled by it,” said Dr. Warren Olanow, professor and chairman of neurology at Mount Sinai School of Medicine in New York. He suspects there are close to a million people in the United States with Parkinson’s. Olanow recently testified before Congress that the movement disorder costs society $27 billion a year in medical bills and lost wages. Parkinson’s is primarily an age-related disease. Symptoms take hold when most of the dopamine-containing cells in a brain region called the substantia nigra die away. But while medicines that target the brain chemical dopamine offer relief in the early days of the disease, in time they stop working effectively. The treatments don’t seem to help the gait disturbances, freezing, falling and dementia that follow the path of this disease.

The answer, Olanow and Dorsey agree, will come from more research and new treatments that protect against Parkinson’s or slow its course. Parkinson’s researchers now know it isn’t only dopamine-containing cells at play in the progressive illness. Olanow said Parkinson’s is characterized by other pathologies spread throughout the brain. Work is under way to develop drug treatments – including gene therapy and stem-cell therapy – to stall the disease process.

Alzheimer’s disease is far more common, with about 4.5 million patients in the U.S. By 2030, this number is expected to double.

In the U.S., the proportion of the population over 65 was 12.4 percent in 2000 and expected to jump to 19.6 percent in 2030, according to the Centers for Disease Control and Prevention.