AAT deficiency can affect people of any race or ethnicity. However, the condition occurs most often in white people of European backgrounds.
If you have first-degree relatives (siblings, parents, or children) with AAT deficiency, you are at a higher risk for the condition. Even so, it does not mean that you will develop one of the diseases related to the condition.
Some risk factors make it more likely that you will develop lung disease if you have AAT deficiency. Cigarette smoking is the leading risk factor for serious lung disease if you have AAT deficiency. Your risk for lung disease also may go up if you breathe in dust, fumes, or other toxic substances.