To determine the extent to which the cost of an effective self-care intervention for primary care patients with knee osteoarthritis (OA) was offset by savings resulting from reduced utilization of ambulatory medical services.
In an attention-controlled clinical trial, 211 patients with knee OA from the general medicine clinic of a municipal hospital were assigned arbitrarily to conditions of self-care education (group E) or attention control (group AC). Group E (n = 105) received individualized instruction and followup emphasizing nonpharmacologic management of joint pain. Group AC (n = 106) received a standard public education presentation and attention-controlling followup. A comprehensive clinical database provided data concerning utilization and cost of health services during the following year.
Only 25 subjects (12%) were lost to followup. The 94 subjects remaining in group E made 528 primary care visits during the year following intervention, compared with 616 visits by the 92 patients remaining in group AC (median visits 5 versus 6, respectively; P < 0.05). Fewer visits translated directly into reduced clinic costs in group E, relative to controls (median costs [1996 dollars] $229 versus $305, respectively; P < 0.05). However, self-care education had no significant effects on utilization and costs of outpatient pharmacy, laboratory, or radiology services over the ensuing year. The cost per patient to deliver the self-care intervention was estimated to be $58.70.
Eighty percent of the cost of delivering effective self-care education to the knee OA patients in this study was offset within 1 year by the reduced frequency and costs of primary care visits. For >50% of patients receiving the intervention, the savings associated with fewer primary care visits exceeded the cost of self-care education.