Aims To examine whether alcohol and other drug (AOD) treatment is related to reduced medical costs of family members.
Design Using the administrative databases of a private, integrated health plan, we matched AOD treatment patients with health plan members without AOD disorders on age, gender and utilization, identifying family members of each group.
Setting Kaiser Permanente Northern California.
Participants Family members of abstinent and non-abstinent AOD treatment patients and control family members.
Measurements We measured abstinence at 1 year post-intake and examined health care costs per member-month of family members of AOD patients and of controls through 5 years. We used generalized estimating equation methods to examine differences in average medical cost per member-month for each year, between family members of abstinent and non-abstinent AOD patients and controls. We used multilevel models to examine 4-year cost trajectories, controlling for pre-intake cost, age, gender and family size.
Results AOD patients’ family members had significantly higher costs and more psychiatric and medical conditions than controls in the pre-treatment year. At 2–5 years, each year family members of AOD patients abstinent at 1 year had similar average per member-month medical costs to controls (e.g. difference at year 5 = $2.63; P > 0.82), whereas costs for family members of non-abstinent patients were higher (e.g. difference at year 5 = $35.59; P = 0.06). Family members of AOD patients not abstinent at 1 year, had a trajectory of increasing medical cost (slope = $10.32; P = 0.03) relative to controls.
Conclusions Successful AOD treatment is related to medical cost reductions for family members, which may be considered a proxy for their improved health.