Effect of Practice Nurse Involvement in Depression Management

Depression is a health priority in many countries and is the most common mental health disorder, globally. Many reviews and analyses have found that collaborative care for patients with depression is effective and cost-effective. A recent study examined levels of practice nurse involvement in clinical-based activities for the management of depression in a real-world Australian setting [BMC Fam Pract. 2014;15:10].

Using risk-adjusted cost-effectiveness, the Primary Care Services Improvement Project (PCSIP) evaluated the cost-effectiveness of a high level model of practice nurse involvement compared to a low level model. Additionally, PCSIP sought to develop a depression state classification framework to use with routinely collected general practice data.   

Nine practices participated in the study, recruited from within Adelaide Northern Division of General Practice, South Australia. The practice nurses were surveyed to determine their level of involvement in clinical-based activities in the management of depression, including patient education, self-management advice, and monitoring of treatment adherence. Based on their responses, involvement was designated as a high or low level model of care. After analysis of the surveys, 6 practices were deemed low level models of care, while the remaining 3 were classified as high level models of care.

The Pen Computer Systems Clinical Audit Tool was used to identify eligible patients with depression in their medical history. Eligible patients ranged in age from 18 to 75 years, regularly visited the practice, were not under regular psychiatric care, not pregnant, not living in a managed care facility, and did not have a severe mental disorder, such as schizophrenia or bipolar disorder. In total, 208 patients were originally recruited for the study; 124 patients for the low level model and 84 patients for the high level model. Of the 208 patients recruited, 54 patients were excluded from the study.

To track the progression of depression, PCSIP developed a model structure for cost-effectiveness analyses of depression management including 6 clinically and economically relevant depression-related states:

• Depressive episode

• Chronic depression

• Hospital admission

• Response

• Remission

• Recover

Patients were then classified based on:

• Depression symptom intensity and timing

• Antidepressant medications

• Psychology and psychiatry referrals

• Emergency department referrals

• Suicide attempts

The duration of a patient’s participation in the study was calculated as the number of days between the first and last day in which a depression state was determined. Depression-free days were calculated as the total number of days in remission or recovery states, while all other states were classified as depression. Although documentation of patient symptoms and their severity varied from practice and general practitioners, most patients, with the exception of 3, followed the proposed depression model structure. No patients died during the study.

While none of the practice nurses reported specific qualifications in the field of mental health care, nurses in the high level model practices attended an average of 1.33 sessions for depression over a 2 year period compared with the nurses in the low level model practices who attended an average of 0.38 sessions. In an unadjusted analysis of the data from 99 patients from the low level model and 55 patients from the high level model, there was a significant difference (P<.05) between models in terms of socioeconomic status of the patient, duration of attendance at the participating practice, and duration of study follow-up.

Unadjusted analyses of the high and low level models of care found no significant difference in the portion of depression-free days (pDFDs). Furthermore, Medicare out-of-hospital cost and total depression-related costs were significantly higher for the high level model compared to the low level model. Out-of-hospital costs for the high level models were $2039, while low level costs were $1502 (P=.005). Total depression related costs were $2374 for high level and $1750 for low level (P=.01). See Table (Below) for more specific costs. Adjusted analyses of the models of care found no significant difference in pDFDs or cost.

The researchers noted some study limitations. Potential bias in the study may be a result of variations in the level of details provided in the general practice medical notes, a particular concern for chronic depression. In future applications, quantifying bias in the classification process may be achieved through a measure of uncertainty for each classification state, according to the study authors. Additional limitations included a relatively small sample size, classification of high or low level model of care based solely on the responses of practice nurses, and the observational study design.

Classifying depression status based on routinely collected clinical data has shown to be feasible, with additional research. In addition, PCSIP’s findings suggest the involvement of practice nurses in the management of patients with depression is only efficient when proper training and support in mental health is available.