Does emphysema effect older people?

It can.... Empysema is a form of copd, usually a result of cigarette smoking. The more cigarettes you smoke over time, the bigger your risk of developing this disease. So, elderly people who have smoked lots of cigarettes over many years are at high risk of developing this disease.
Yes. Because emphysema happens over a period of years, most patients are older when they develop symptoms of it. Because there is such a gradual deterioration in lung function sometimes patients have mild symptoms for many months before they are diagnosed with emphysema.
Yes. It depends on your definition of "older". ;) emphysema is damage to the lungs, commonly from smoking, but it is rarely caused by a genetic condition called "alpha one antitrypsin" deficiency. People who have low levels of this enzyme develop emphysema at a younger age, and it is worse if those same people smoke. Usually emphysema is seen in smokers in their 60's and up, but can be seen earlier.