Discussion
The strength of our study was our ability to examine a relatively large number of primary care practices and patients, and to explore, in a longitudinal manner, an important mental health care issue in primary care. With appropriate caveats concerning the generalizability of findings from physicians who choose to use electronic medical records, this study adds additional information to the field’s growing body of knowledge.5
Our study confirmed that depression management and antidepressant prescribing are important aspects of primary care practice. During 1996, 1 of every 48 women and 1 of every 104 men who were patients in PPRNet practices received a new diagnosis of depression. Of those diagnosed with depression, almost half received an antidepressant prescription within 5 days of the diagnosis. By the end of 1996, nearly two thirds of these patients had received such a prescription, a proportion similar to that found in the standard care arm of a primary care depression trial.8 The vast majority of treated patients received SSRIs, a finding consistent with the increasing use of these agents among outpatient psychiatrists.9 SSRI antidepressants are better tolerated than older agents and do not increase overall treatment costs,10 justifying their widespread use.
Nine of every 10 patients treated with antidepressants had at least one follow-up contact with the practice. On average, these patients had more than 5 contacts in the 6 months immediately following the diagnosis. This degree of follow-up is consistent with the AHCPR guideline, which recommends contact every 10 to 14 days for the first 6 to 8 weeks of treatment and every 4 to 12 weeks after that.3 This finding is in contrast with the concern that this degree of follow-up is not provided in primary care settings.1
Obscured in the overall analyses are the nearly 10-fold interpractice variations in the diagnosis of depression (0.8% to 8.6% for both 1996 and earlier diagnoses) and the use of antidepressants (1.9% to 13.6%). Patient-level factors may account for some of this variation. It is likely, though, that there are physician-level differences in the ability to recognize, the willingness to diagnose, and the comfort in the treatment of depression.1,11 Excluding minor depression and dysthymia, which may be as prevalent, epidemiologic studies have found a prevalence of depression from 6% to 8% in primary care samples.12 Only 4 of the 39 PPRNet practices in our study had a 6% or greater prevalence of depression. However, 21 practices prescribed antidepressants to 6% or more of their patients. Since many of the diagnoses for these patients are not accepted indications for antidepressants, it may be that physicians are treating more depression than they are recording. Nonetheless, it is clear that opportunities remain for improvement in depression recognition among nearly half of the study practices.
Limitations
Several limitations to our study are important. Diagnoses listed in the electronic medical record reflect physician opinion and are not validated against a gold standard. The PPRNet database has limited information about nonpharmacologic treatment, so the extent to which patients received counseling or watchful waiting is unknown. Both of these strategies are endorsed by the AHCPR guidelines for patients with mild depression.3 The nature of the database also makes it difficult to be certain about the duration of pharmacotherapy or patient compliance with prescribed medication. Finally, it is uncertain whether clinicians actually addressed the patient’s depression during follow-up contacts.
Conclusions
Our study reveals the interpractice variations of diagnosing depression and prescribing antidepressants in primary care. Patients with newly diagnosed depression were followed up in a manner consistent with published guidelines. Opportunities for increased detection and treatment of depression exist in approximately half of the study practices. The unique features of PPRNet provide opportunities for future work in this area.