DES MOINES — The number of Iowans who gamble jumped 9 percent from 2011 to 2013, according to a study published Tuesday.People dealing with substance abuse or mental health issues were more likely to be at-risk for “problem gambling,” the study also showed.In 2013, more than 78 percent of adults said they had gambled in the past 12 months, according to the report prepared by the University of Northern Iowa’s Center for Social and Behavioral Research for the Iowa Department of Public Health’s Gambling Treatment Program.