Smoking is an extremely important risk factor that anyone with Crohn’s Disease should absolutely eliminate. A smoker with Crohn’s Disease is much more likely to develop strictures, blockages, or fistulas. They’re more likely to have complications that require surgery. Crohn’s Disease can affect people of all ages; there is no risk factor based on age. Symptoms can start at a very early age; however, Crohn’s Disease typically presents in the second or third decade of life.