People with a family history of depression, anxiety and alcohol and drug dependence are not only likely to develop these conditions, but tend to suffer more seriously and need more treatment, a study has found.

In the nearly 30-year study in New Zealand, researchers tracked 981 people from the time they were three years old until they were 32, and collected data on their psychiatric conditions as well as those of their family members.

Four psychiatric disorders were studied: depression, anxiety, alcohol dependence and drug dependence, they write in the latest issue of the Archives of General Psychiatry.

While it is well-known that a positive family history increases the likelihood of an individual developing any of these four conditions, this study sought to find out how seriously they were affected, the researchers added.

The study showed participants with a positive family history had more recurrences of these conditions and they reported more disruptions caused to their lives, families, friends and work.

“Family history was associated with greater service use for all four disorders (but not significantly for anxiety disorders),” the researchers state.

However, family history did not appear to be linked to early onset of any of the four conditions.

“Among those with depression, anxiety disorder, alcohol dependence and drug dependence, a family history screen may help determine whose illness will recur, whose illness will cause the greatest impairment and who will be the most likely to use treatment resources,” they wrote.

“Family history may identify a subgroup in need of primary or early intervention, and for whom treatments appropriate for recurrent, highly disabling disorder may be needed.”

SOURCE: Archives of General Psychiatry, July 2009.