African-Americans and Caribbean blacks, who are victims of discrimination, face heightened risk of developing mental disorders including anxiety, depression and substance abuse, according to a new study led by the University of North Carolina.

The researchers said that discrimination in terms of disrespect and arrogance does not seem to play a role in the increased risk of mental disorders. However, when hostile and character-based discrimination is combined with disrespect and condescension, African-American and Caribbean black adults are at a significant risk for mental health problems.

"When it comes to mental health, our results suggest that the type and frequency of discrimination matters," co-author and professor Christopher Salas-Wright at the University of Texas at Austin's School of Social Work said in a press release. "It seems that it is the ongoing experience of multiple types of discrimination, including disrespect, condescension, hostile and character-based discrimination, which negatively impacts mental health."

"Perceived discrimination is an often overlooked but major source of health-related stress, with effects comparable to other major stressors such as the death of a loved one or the loss of a job," co-author Trenette Clark from the School of Social Work at the University of North Carolina, Chapel Hill, said. "Our study shows that the risk for mental health and behavioral disorders varies according to the types and frequency of discriminatory experiences."

For the study, the researchers used data from the National Survey of American Life. The survey about the mental health of black and non-Hispanic white populations in the United States included a sample of 4,462 African American and Caribbean black respondents between 18 and 65 years of age.

In order to determine the health effects of discrimination of different types, the researchers subjected participants to questions like "How often do you receive poorer service than others at restaurants or stores?" (disrespectful discrimination), "How often do people act as if they're better than you are" (condescending discrimination), "How often are you viewed as dishonest?" (character-based discrimination), and "How often are you threatened or harassed?" (hostile discrimination).

The researchers found that 83 percent of the participants faced discrimination during the past year. Nearly 50 percent of the participants reported recurrent discriminations and approximately one-seventh (14.7%) reported frequent experiences of discriminations. The participants belonging to the last two groups were more likely to report symptoms for depressive disorder, alcohol-use and illicit drug-use disorders.

"Although most of our sample reported recent discrimination, most did not report mental health and substance use disorders, which speaks to their strength and resilience," Clark said. "Factors such as ethnic identity, spirituality and religiosity have been found to help protect against risk factors such as everyday discrimination."

The finding is published in the journal Addictive Behaviors.