Last of four parts

By Katie Doyle and Chelsea Sheasley

The Boston University Statehouse Program

Who will use medical pot in Massachusetts?

Although only a few of the medical marijuana states collect detailed demographics, the numbers suggest the likely users will be middle-aged men.

Patients in Arizona and Colorado, the only states to provide patient data by gender, are overwhelmingly male. In Arizona, 73 percent of approved applicants are men. In Colorado, males account for 68 percent of users.

This breakdown appears to mirror recreational marijuana use nationwide. According to the annual National Survey on Drug Use, conducted by the U.S. Department of Health and Human Services, males continue to use marijuana more than women — at a rate of 11.2 percent of the population compared to 6.8 percent.

The four states that report medical marijuana data by age found users tend to be older. The average age of a medical marijuana patient in Colorado is 41; in Montana, 46. In Nevada, the highest percentage of users fall between 55 and 60 years old.

In Arizona, however, the highest percentage of users falls between 18 and 30 years.

Only a few states report whether minors are enrolled in their medical marijuana programs. The numbers range from 45 in Colorado to two in Nevada, out of 3,558 patients, and one in Montana, out of 8,681 patients. The Massachusetts law is silent on whether minors will be eligible for its program.

Eleven states publish data on the number of registered patients, six do not. From the available figures, Colorado has the highest registered medical marijuana use: 107,666 people, about 2.1 percent of the state’s population, are part of the program.

Oregon and Michigan have the next highest rate of use; 1.5 percent of Oregonians use medical marijuana; in Michigan it is 1.2 percent.

The rest of the states have less than 1 percent of their population enrolled in medical marijuana programs.

The available numbers also suggest the rate of medical marijuana use tends to creep up through the years as it becomes more available and socially acceptable:

* Colorado recorded 5, 051 patients in January 2009, eight years after medical marijuana was approved. A year later, that number jumped to 53,038. By this September Colorado reported 107,666 patients.

* Arizona approved 579 applications in April 2011, less than a year after the medical marijuana program began. The following year, that number was 25,543. Last month, two years after passing the ballot initiative, Arizona had 33,601 cardholders.

* California, which approved medical marijuana in 1996, issued just 85 cards in fiscal 2004. As the program accelerated and more dispensaries were added, 4,150 cards were issued in fiscal 2005, followed by 10,274 in the year after that. The number has fluctuated since then, reaching a high of 12,659 in fiscal 2009.

The numbers can fall quickly if acquiring the medical pot becomes more problematic. The number of registered California patients dropped to 7,801 in fiscal 2011 following a series of federal raids on dispensaries.

Montana’s Department of Public Health and Human Services reported 88 enrolled patients in March of 2005. In September 2009 the number was up to 3,921. By June 2011, the state had 30,000 enrolled patients.

Then came federal raids in 13 cities and the closure of dispensaries in Montana. The incidents had a chilling effect, bringing the number of participants in the program down to 8,681 patients in June 2012.