( CNN ) -- It had been a little more than four months since completing my second space shuttle mission , STS-59 , on the shuttle Endeavour . I was finishing my annual flight physical at the Johnson Space Center Flight Medicine Clinic . The words from the flight surgeon were as expected : I was in great condition with nothing of note . Then I asked the doctor to look at my right shoulder because my racquetball game was suffering . He asked if I had pain . I told him I was n't in pain , but my right arm did not swing naturally when I walked . This comment must have set off some alarm , because he observed my walk down the hall and quickly said he would take me downtown to the Texas Medical Center the next day . I remember saying , `` I do n't believe we can see an orthopedic surgeon that quickly . '' He merely noted that we were going to a neurologist . Little did I know that next day would change my life so quickly . The neurologist spent five minutes with me before saying that I had Parkinson 's disease . He added I would have to undergo several separate tests to prove that I did n't have some other neurological disorder . Parkinson 's disease is diagnosed by the process of eliminating other possible diseases . After several tests , the diagnosis was confirmed . This was December 1995 . Beat goes on for music producer diagnosed with multiple sclerosis . To their credit , the flight surgeons asked me what I wanted to do about flying . I quickly said I wanted to continue with all activities , including standing in line for another space shuttle mission . I kept my condition a secret to all , except my wife and my children . I assumed senior NASA management were told , but no one ever spoke to me about the disease . They protected my privacy . I continued my normal duties and was subsequently offered my third shuttle mission -- STS-76 , which included a planned space walk . The mission was highly successful . One year after that mission , I left NASA for a job in the private sector supporting human space flight . With the exception of my closest friends and family , I kept my condition a secret for almost 15 years . My reason for secrecy was simple : People did not need to know . Now I 'm an advocate for Parkinson 's disease awareness . Having Parkinson 's disease is no reason to stop living life to its fullest extent . Yes , as the disease progresses I have had to change the way I do certain activities , but I continue to do them . I have a keen awareness now of the stress my disease places on my loved ones who provide me encouragement and tender loving care . The caregivers to a person with Parkinson 's are the people who give so much of their lives to care for a loved one . My wife is my caregiver and I am acutely aware of her sacrifices . Parkinson 's disease affects more than just the patient . The patient needs to understand the caregiver is there to help . So do not let Parkinson 's disease control your life . You may do things slower , or you may not be able to do things you once did as easily . It is not the end of the world . Do not give up trying . 8-year-old writes book on hearing loss .
Astronaut Rich Clifford was diagnosed with Parkinson 's disease in 1995 . It did n't stop him from going on a third shuttle mission and completing a spacewalk . Clifford kept his illness a secret for 15 years .