It found morbidity in children with asthma was linked to the frequency of depressive symptoms in their mothers.
The researchers warn that doctors treating children suffering frequent asthma exacerbations should be alert for signs of depression in their primary caregivers.
The study included 262 African-American mothers of children with asthma. Interviews carried out six months apart were used to determine frequency of depressive symptoms in the mothers, and of asthma symptoms in the children.
Reported increases in maternal symptoms of depression were followed by increased asthma in children. But the reverse was not true.
Lead researcher Dr Kristin Riekert, paediatric psychologist at the Johns Hopkins Adherence Research Center, Maryland, said the data clearly showed that increased child asthma symptoms followed increased maternal depression.
'Intuitively, it may seem that we are dealing with a chicken and egg situation, but our study suggests otherwise,' she added.