For pharmacists in the business of mood-altering drugs, a recent study conducted through the Yale School of Management might prompt a move to Tennessee.

The study examined the geographic distribution of the use of antidepressant, antipsychotic and stimulant medications, and identified a large cluster centered on Tennessee where the use of these drug classes is 40 percent higher than the United States average. While the research has yet to untangle the “complex causal web of what’s happening” in the region to determine why those residents are more drug-dependent, assistant professor of organizational behavior Marissa King said she is interested in looking at the effect government regulation has on the prescription of these drugs. The study, which first appeared online Jan. 7, will be published in a forthcoming issue of the journal Health & Place.

King and co-author Connor Essick GRD ’12 compared their data on the prescription of these drug classes to data on the prevalence of conditions that would warrant elevated use, such as depression and ADHD. They found that “use of these medications doesn’t match patterns of underlying disease prevalence,” Essick said.

Rather, King and Essick said they believe the spike in prescriptions is more likely due to factors related to pharmaceutical marketing.

King explained that some states enforce regulations on pharmaceutical marketing, while the states in this cluster do not. To quantify what impact advertising restrictions would have on prescription drug use, she plans on comparing data from states inside the cluster to data from states with stricter regulations, she said.

“We’ve identified a puzzle that people don’t have a clear answer to, but we’re looking at marketing efforts and prescribing behaviors, and we think marketing might be one of the primary influences affecting this phenomenon,” King said.

The role of pharmaceutical marketing has implications for the field of business as well as public health, Essick said. From the business perspective, these findings have introduced new questions about the “diffusion of a new drug on the market” and about “how physicians decide to prescribe a drug,” he said. Companies hoping to sell a new drug may now take into account the effect marketing regulations have on the number of drugs prescribed. The public health realm is now interested in how pharmaceutical marketing might affect the decisions people make about taking prescription drugs, he added.

“The outcome here isn’t necessarily negative — it’s not saying that pharmaceutical marketing is a bad thing,” Essick said. “It’s just saying that pharmaceutical marketing has an influence, otherwise companies wouldn’t invest the kind of money they do in marketing.”

An even more important result of this research, according to Essick, is that it reinforces the idea that nonmedical factors affect people’s health and their access to health resources. In addition to the role of marketing efforts, public perception of an individual seeking treatment might also affect the prescription of psychotropic drugs, King said.

Her next goal is to examine more closely why this spike in prescription drug use exists in the Tennessee region. However, King said identifying a single cause will prove challenging given the numerous factors that go into an individual’s decision to take antidepressants, antipsychotics or stimulants.

Essick said obtaining accurate data presents another obstacle, since pharmaceutical companies are not always completely transparent with the data they disclose to the public. Even data that is disclosed is often “difficult to use in a research perspective because it’s too specific, it’s not tangible and it’s not terribly clean,” he said.

Still, Harvard associate professor of psychology Simon Caine said this research is relevant to the general public. People should know how their local prescription trends compare to trends in other parts of the country, if only to realize that they have options outside of their states, he said. Elucidating the process of drug prescription is an important step in revealing the range of medical options available to patients seeking treatment, and no patient should have to make a decision without exploring the variety of options, he added.

While the use of each of the drug classes of antidepressants, antipsychotics and stimulants varies slightly, King and Essick’s study found that these drugs are prescribed at the lowest levels in the western part of the country.