Collaborative care has a broad and extensive evidence base supporting its use as a model of care for primary care patients with depression and anxiety disorders (
1–
3). Given the widespread implementation of collaborative care, many practicing psychiatrists and psychiatry trainees are caring for patients with depression and anxiety disorders by using collaborative care. Psychiatrists practicing in collaborative settings will also encounter and treat patients with illnesses other than major depression or anxiety disorders (
4,
5). Our clinical work has revealed that in some safety-net primary care settings, up to 15% of patients treated in collaborative care are diagnosed as having bipolar disorder (
6).
Reports on the clinical epidemiology of bipolar disorder support these findings (
7,
8). The prevalence of bipolar disorder in primary care settings is approximately twice the prevalence in the general population (
7,
9). Treatment seeking by patients with bipolar disorder is divided about equally between primary care and specialty mental health settings (
7,
10). Work in one statewide collaborative care program showed that only a minority of patients with bipolar disorder treated in primary care were referred to specialty mental health care (
6). Reasons for this pattern of service use may have to do with limited access to the specialty mental health setting, but we have observed that use of the primary care setting can also reflect patient preference. For patients already presenting to primary care settings, collaborative care is one population-based care model that may help to support primary care clinicians in caring for individuals with bipolar disorder.
Diagnosis in Primary Care
Accurate diagnosis of bipolar disorder can be difficult in any setting (
11). Surprisingly, routine features of the primary care setting can sometimes support a robust diagnostic process. For example, unlike the situation in some specialty care settings in which record retrieval may fall to physicians or other clinicians, many primary care clinics employ clinic staff who can efficiently request and obtain past treatment records. In addition, primary care clinicians as well as their clinic staff often have long-term relationships with patients, with relatively frequent contacts, presenting multiple opportunities for clinical observation over time. Timely access to appointments can be easier for patients seen in primary care, and patients can often talk over symptoms or problems on the phone with primary care clinicians (
12).
Collaborative care provides even more opportunities than primary care for repeated observation through symptom assessment, clinical examinations, and laboratory studies in primary care. Care managers in collaborative care usually have either in-person or phone contacts with patients initially weekly or every other week at the beginning of treatment (
13). This information is then reported to the collaborative care psychiatrist weekly during consultation, giving many opportunities to revise and update diagnostic impressions through an iterative process (
12,
13). Having many opportunities to revise a diagnostic impression, and knowing that the diagnosis can be revised over time, can increase the consulting psychiatrist’s comfort with diagnosing bipolar disorder in primary care (
14).
Collaborative care includes use of screening instruments and symptom measurements. Although clinicians in many settings use symptom measures, their use in collaborative care is routine and used to inform treatment decisions. For example, the nine-item Patient Health Questionnaire (PHQ-9) is a patient-reported symptom measure and is used as a screening and symptom measure of depressive symptoms (
15). Using the PHQ-9 and similar instruments permits measurement-based care, which improves the quality of care and improves patient outcomes in comparison with usual care (
16). However, screening for and measuring symptoms of bipolar disorder are more difficult than doing so for major depression because no instrument exists that works as both a screening and symptom measurement tool. All existing screening measures assess for lifetime experience of hypomania or mania (
17). No screening measures assess current symptom severity. Only one bipolar disorder symptom measure, the Internal State Scale, involves patient self-report of depression and manic symptoms and can discriminate mood states (
17,
18). In practice, many clinicians assess and track depressive symptoms of individuals with bipolar disorder using the PHQ-9, although the measure does not assess manic symptoms.
One screening measure, the Mood Disorder Questionnaire (MDQ) (
19), was commonly used in primary care clinics that we consulted prior to and in the initial stages of implementation of collaborative care. In primary care settings the MDQ commonly results in false positives, meaning that many individuals who screen as positive do not have bipolar disorder on the basis of structured interview or clinical examination (
9,
19). This is due to the lower prevalence of bipolar disorder in primary care in comparison with specialty care settings in which the MDQ was initially studied and validated (
20). A decrease in illness prevalence results in a decrease in the positive predictive value of screening measures, resulting in an increase in false positives (
19). Clinicians electing to use the MDQ as a screening measure should recognize that perhaps fewer than half the individuals in primary care with a positive screening result on this measure will actually have bipolar disorder on the basis of clinical examination and that alternative diagnoses—such as posttraumatic stress disorder, substance use problems, borderline personality disorder, or other diagnoses—could account for a positive screening result on the MDQ. If used in primary care settings, its use should be limited to screening, and positive findings should initiate a more definitive diagnostic evaluation.
More recently, we have used the Composite International Diagnostic Interview (CIDI) 3.0 bipolar disorder measure, which is a structured interview used in epidemiologic studies (
6,
21). Use of this measure by collaborative care managers can lead to structured and consistent assessment of past hypomanic or manic symptoms when a patient is presenting with current depression. We do not diagnose bipolar disorder on the basis of results of this measure alone. As in specialty settings, we use results from this measure; current and past clinical information, including mental status examination findings; family history; past treatment responses; and other information to arrive at a provisional diagnosis of bipolar disorder. This provisional diagnosis can be revised and edited through repeated observation in primary care. Phelps has proposed alternative strategies for improving accuracy of diagnosis of bipolar disorder in primary care (
22).
Research has shown that higher quality of care for individuals diagnosed as having bipolar disorder is often provided in specialty care settings (
7), although in clinical practice we have encountered patients deciding to return to primary care for treatment or declining specialty mental health care referral because of patient preference. Long-term treatment plans in specialty care may at times be interrupted by patients returning to primary care for treatment, suggesting a need for ways to identify and provide treatment to patients with bipolar disorder already presenting to primary care.
Although treatment challenges exist in primary care, it can be difficult even in specialty care settings to consistently achieve optimal treatment outcomes for individuals with bipolar disorder. For example, one finding from the Systematic Treatment Enhancement Program for Bipolar Disorder (a large treatment study in specialty settings providing high-quality care to individuals with bipolar disorder) was that among individuals symptomatic at baseline (N=1,469), 58% achieved remission, but half of the patients who had remission experienced recurrence during the next two years (
23). In addition, systematic care management programs tested in randomized trials (
24,
25) have shown that patients assigned to the systematic care intervention had significant reductions in manic symptom burden, improvements in treatment satisfaction, and quality of life, but no reduction in depressive symptom burden over two to three years of follow-up.
Because patients with bipolar disorder may present for treatment in primary care, we view attempts to provide treatment for these patients as necessary to reach a larger proportion of patients with bipolar disorder. Involving consulting psychiatrists in primary care may be one way of improving the quality of care for patients with bipolar disorder treated in primary care.
Three Perspectives
In this section we describe three perspectives of diagnosing and treating patients with bipolar disorder in primary care. The first perspective includes a patient case and clinician views derived from a case summary of a previously published report and study of collaborative care psychiatrists (
14,
26). The second is from the perspective of a larger population of primary care patients with bipolar disorder. The third is from an administrative or health system perspective. Although not described in this article, a possible fourth perspective would be from the population view of the entire population of individuals with bipolar disorder (
10).
Patient Case and Clinicians’ Views
This case is described in detail elsewhere (
26). In short, a 36-year-old man presented to primary care, reporting two years of depression and irritability. He was a patient in the primary care clinic for care of asthma. He was diagnosed as having major depression and treated with bupropion and sertraline, plus as-needed symptomatic treatment with trazodone and lorazepam. Because of nonresponse over seven months, stressors including job loss and separation from his wife, and escalating alcohol use, his treatment was intensified to treatment with collaborative care. The care manager used a structured assessment that included screening instruments and symptom measures to gather historical and current illness clinical information from the patient. The patient screened positive for bipolar disorder on the clinic’s screening measure, so the care manager asked many follow-up and clarifying questions. The care manager also talked directly to the primary care clinician. Results were discussed later that week with a consulting psychiatrist, who had an initial impression of bipolar disorder and made treatment recommendations.
Over several months the patient returned to primary care regularly to meet with the care manager and primary care clinicians, and the care manager talked to the psychiatrist weekly. Despite several steps of treatment in primary care, the patient did not improve and was referred to direct specialty care in a psychiatry clinic, although the patient attended only one specialty clinic appointment and then returned to primary care. Several additional treatment steps were taken in primary care on the basis of recommendations from the consulting psychiatrist, including treatment of alcohol use, and over several months the patient achieved treatment goals of remission of depression, improved psychosocial functioning, and significant reduction in alcohol use.
This case highlights several points. First, as in this case, patients with bipolar disorder in primary care have a high symptom burden and significant psychosocial impairment (
6). Second, as in specialty care, achieving treatment goals for some patients, including depression remission, required persistent assessment and several changes in treatment (
23–
25). Third, the patient attended a specialty care appointment, but because of his preference, he returned to primary care for continued treatment. Fourth, clinicians were willing to treat the patient and modify treatment priorities over time.
Interviews with consulting psychiatrists who have cared for patients with bipolar disorder in primary care revealed several themes, including the importance of working as a collaborative care team, strengths of collaborative care in evaluating and treating patients with bipolar disorder, and the need for consulting psychiatrists to adapt specialty skills to primary care (
14). This case example illustrates these themes by describing how collaborative care team members work together to recognize bipolar disorder and provide high-quality care to patients in primary care, including monitoring response to treatment and adjusting treatments when needed —which require adapting specialty skills to primary care. Furthermore, the strengths of primary care clinics, and in this case the patient’s preference for treatment in primary care, contributed to the patient’s and team’s persistence in intensifying treatment.
Larger Population of Primary Care Patients With Bipolar Disorder
Our experience working as collaborative care psychiatrists has shown that over time, patients with illnesses other than depression or anxiety disorders, such as bipolar disorder, are treated in primary care using the collaborative care model. Because we, and other consulting psychiatrists, were unsure of how to provide effective care for patients with bipolar disorder in primary care, we sought to first describe the characteristics of patients with bipolar disorder in primary care. Cerimele and colleagues found that patients’ severity of reported symptoms was high and that psychosocial stressors were common (
6). Notably, the majority of primary care patients with bipolar disorder had received past outpatient or inpatient specialty mental health care. The authors interpreted these findings to suggest that there are not distinct groups of patients with bipolar disorder in either primary care or specialty care; instead, patients with bipolar disorder move between primary and specialty care settings.
We also learned practice-based lessons from a real-world example of implementing and maintaining a collaborative care program in a federally qualified health center over eight years. A series of 915 patients with bipolar disorder in primary care were cared for in a collaborative care program (unpublished study). Care of all primary care patients in this program was actively directed by the collaborative care psychiatrist. The care manager in this program used a semistructured interview, the CIDI 3.0, with patients who were currently depressed as part of the process of assessing a history of past hypomania or mania.
Bipolar disorder diagnosis was established through a process of history assessment, structured interview results, following patients over time to assess symptoms, and case review with the collaborative care psychiatrist for each case. Among the 915 patients with bipolar disorder, approximately one half of patients received a diagnosis of bipolar disorder I, over one-third bipolar disorder unspecified, and the rest received a diagnosis of bipolar disorder II. Findings similar to those seen among patients in specialty care settings included a high prevalence of past trauma exposure and a high prevalence of co-occurring illnesses such as anxiety disorders. Few patients referred from primary care to specialty care attended the referral appointments.
Health System or Administrators
Health system barriers to caring for patients with bipolar disorder include general barriers to maintaining collaborative care, including primary care clinician questions about caring for patients with psychiatric illnesses, managing an engaged system, establishing relationships with clinic medical directors or system executives, and accessing adequate funding for team-based care (
13).
Clinical barriers include addressing consulting psychiatrists’ and primary care clinicians’ concerns and questions about treating patients with more complex illnesses such as bipolar disorder. Concerns tend to center around questions of whether an accurate diagnosis can be made, whether the medication treatments for bipolar disorder can be prescribed safely by primary care clinicians, and whether risk of self-harm or medical complications of treatment can be evaluated and managed.
We have found that an easily accessible consulting psychiatrist can address the worry and concerns that primary care clinicians—both physicians and behavioral health clinicians—may have about caring for patients with bipolar disorder or other complex conditions in the primary care setting. Collaborative care programs often include emergency phone access to the consulting psychiatrist for phone consultation. Although infrequently used, knowledge of rapid and easy access to the psychiatric consultant, something not familiar to most primary care clinicians, can significantly ease the anxiety of the treatment team. It is essential that the psychiatric consultant make every effort to respond in a timely fashion to these occasional urgent requests.
To improve clinician access to point-of-care education and decision support, we developed and distributed to primary care clinicians a written roadmap or treatment algorithm in pocket-card form for the treatment of patients with bipolar disorder. The card included a description of the diagnostic procedure for bipolar disorder, the need for clinical engagement, provision of accurate information and support to patients and families, and details, including dosing, of medications commonly used to treat bipolar disorder. The card also included information on side effects and requirements for examination and laboratory monitoring. Additional information and opportunities to respond to questions were presented at regular didactic presentations led by the collaborative care psychiatrist to the care managers and primary care clinicians.
Primary care leadership interest in collaborative care can also help to overcome barriers by creating the norm that care of patients with a wide range of psychiatric conditions can be standard practice in the primary care organization and that the practice is valued as one of the organization’s areas of distinction and excellence. A physician recruitment process that clarifies these values, and the expectation that the clinician will participate in the collaborative care model, can be effective in perpetuating these values and practices. In addition, many primary care medical directors recognize that collaborative care can provide primary care clinicians and patients with access to specialty mental health care and help to improve outcomes of primary care patients, and it may improve physician and clinic performance on metrics related to reimbursement. An approachable and responsive collaborative care team can help primary care clinicians feel supported in caring for patients with other psychiatric conditions. In return and with guidance, primary care clinicians may be more likely to stretch their clinical practice by caring for patients with bipolar disorder.
Surprisingly, many aspects of the primary care setting are not barriers but strengths for the care of patients with bipolar disorder. These include rapid access to clinical contact when needed regularly or urgently and the ready access to laboratory monitoring facilities, both of which can be problems in the specialty mental health sector. Shared access to and interpretation of laboratory results by the collaborative care psychiatrist and primary care clinicians, such as when reviewing lithium concentration and associated studies, can help to address common concerns that primary care clinicians may have about safe treatment of patients with medications such as lithium. Also, the use of a roadmap or algorithm may lead to more systematic treatment, decreasing use of treatments not supported by the evidence base.
Conclusion and Future Directions
In conclusion, primary care clinics and systems are increasingly implementing collaborative care models to care for specific populations of patients with psychiatric illnesses in primary care. Over time, clinicians working in primary care are likely to encounter patients with illnesses other than depression or anxiety disorder, such as bipolar disorder. In addition, equal proportions of patients with bipolar disorder report having received treatment in primary care settings and specialty care settings over the past 12 months. Collaborative care is one population-based treatment strategy that can increase the proportion of individuals with bipolar disorder who are exposed to high-quality psychiatric care, such as appropriate medication treatment and laboratory monitoring.
We recognize that use of collaborative care to treat patients with bipolar disorder in primary care involves applying an existing model of care developed to treat patients with depression and anxiety disorders to a group of patients with perhaps more complicated psychiatric illnesses. It is unknown whether this strategy is optimal for patients with bipolar disorder in primary care or whether other strategies could lead to better bipolar disorder outcomes. However, patients with bipolar disorder are already presenting to primary care settings, and the collaborative care model is one way that psychiatrists can help support primary care clinicians who treat patients with bipolar disorder. The clinical experiences of consulting psychiatrists working with this population in primary care have provided some clinical strategies.
A large pragmatic clinical trial (
27) is currently underway comparing two models of care, collaborative care and telehealth referral, for primary care patients with complex psychiatric disorders, including bipolar disorder, in rural federally qualified health centers. Results will inform how best to care for patients with bipolar disorder who are encountered in primary care settings.