Synthetic marijuana linked to illicit drug use, violent behavior and high-risk sex, according to a new study.
Packets of synthetic marijuana illegally sold in New York City are put on display at a news conference held by New York state Senator Jeff Klein in New York on Aug. 12, 2015. REUTERS

Drug abuse has a long history in the U.S. with the highest number of people dying in the past two decades from drug overdose. A new study by personal-finance website WalletHub, released Sunday, highlighted the states in the U.S. with the maximum drug abuse cases.

The fight against drugs was first initiated when Former President Richard Nixon declared a "war on drugs" in 1971. He increased the size and presence of federal drug control agencies in the nation and also initiated measures such as mandatory sentencing and no-knock warrants, according to Drug Policy Alliance, a New York City-based not-for-profit.

However, it was not enough. The new study revealed that District of Columbia, Vermont, Colorado, Delaware, and Rhode Island, were the top five states in the nation in terms of drug consumption.

Read: How Do Drugs Get Into US?

The factors that contributed to these states topping the drug use chart were police arrests and overdose rates to opioid prescriptions and what the report called "meth-lab incidents" per capita.

The report said the District of Columbia has the highest percentage of adults who did not receive treatment for illicit drug use in the past year, at 3.21 percent.

Colorado has the highest percentage of teens who used illegal drugs in the past month, at 14.58 percent. That is 2.5 times that of Iowa, which has the lowest rate, at 6.31 percent.

Charles Smith, the Director of the Behavioral Health Division of the State Department of Human Services, said, “It’s always worrisome when we look at Colorado and other mountain states for substance abuse and serious mental illness," according to Aspen Ridge Recovery, a drug addiction treatment center in Colorado.

Vermont has clearly seen a spike in deaths due to drug overdose in the past few years. Annual overdose deaths from opioids overall have nearly doubled since 2004, and emergency department visits for opioids have increased about 50 percent since 2009.

Philadelphia's West Kensington and Fairhill neighborhoods act as the primary origin for people in Delaware to get heroin, according to Delaware Online.

According to a survey in 2015, Rhode Islanders continued using marijuana and other drugs more than anywhere else in the country, reports said. "The survey is probably an accurate portrayal, and one we’ve seen trending for a long time," said Rebecca Boss, deputy director of the state Department of Behavioral Healthcare, Developmental Disabilities and Hospitals.

Alabama has 142.9 opioid pain reliever prescriptions for every 100 residents, which is the highest in the nation. Last year, reports had surfaced claiming pain killer manufacturers and their partners had hired an average of 18 lobbyists in Alabama each year since 2006.

The WalletHub study also revealed West Virginia has 42 drug overdose deaths for every 100,000 residents. A February analysis by the West Virginia Health Statistics Center showed at least 818 people in the state died of drug overdoses in 2016 — four times more the number in 2001.

"We are seeing an unprecedented rise in the overdose deaths related to opioids," said Rahul Gupta, the commissioner of the Department of Health and Human Resources' Bureau for Public Health, reports said. "It seems we have not yet peaked."