A new study has reveals that people who smoke marijuana at the age of 18, especially heavy users, are more likely to end up on disability by the age of 59.
The Associated Press reports that Anna‐Karin Danielsson and several colleagues of the Karolinska Institute in Stockholm analyzed data from a large study that included almost 50,000 Swedish men born between 1949 and 1951 and conscripted into compulsory military service in 1969 and 1970.
When the men entered the military, they were asked about their drug, tobacco and alcohol use, as well as questions about their family and social backgrounds, school performance, behavior, psychological issues and general health.
Next, the study team looked at data from the Swedish national social insurance agency, the education registry and labor market statistics to see how many were granted disability pensions through 2008.
The researchers were shocked to discover that men who used marijuana more than 50 times before the age of 18 were 30 percent more likely to go on disability sometime between the ages of 40 and 59.
"There is reason to believe that the associations found in our study develop over a long period of time and are intertwined with problems in the labor market, in the social security system, and with the individual," said Danielsson
A similar pattern was seen for young men who used pot less frequently, with the chance of being on disability in middle age rising with increasing pot use at age 18.
Researchers also adjusted for factors such as socioeconomic background, other substance use by age 18, psychiatric diagnoses and other health problems. However, the link remained statistically significant for the heaviest users who had smoked pot more than 50 times as young men.
Danielsson said that smoking marijuana at a young age may increase the risk of negative social consequences later on in life, and that prior studies have shown frequent marijuana use increases the risk of using other, more damaging drugs.
"It may be the case that adolescent cannabis use may lead to a series of negative life events such as, for example, subsequent illicit drug use, illness (e.g., dependence) and associated disability pensions," she said.
She also noted that it is unclear whether the use of marijuana in adolescence or was an early sign of psychiatric or social factors that later contributed to disability.
However, the study authors conclude that despite the study's limitations, the findings reveal the need for further studies on marijuana and other illicit drug use in relation to possible health and social consequences.
Marijuana is one of the most common and easily accessed drugs in the world, with 77 million European users. In the United States, Colorado and Washington became the first states to legalize the possession and use of recreational marijuana by adults in 2012.