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Abstract

Objective: Bipolar disorder is a recurrent disorder for the vast majority of patients, and hospitalization is normally used to control severe symptoms. The goals of treating bipolar disorder include symptomatic remission, full return of psychosocial functioning, and prevention of relapses/recurrences. Rehospitalization, however, becomes necessary with the relapse/recurrence of severe symptoms. The purpose of the present study was therefore to investigate the risk factors affecting the time to rehospitalization.

Method: Rehospitalization status was monitored for all patients with bipolar I disorder discharged from Kai-Suan Psychiatric Hospital between 1 January 2002 and 31 December 2004. Patients were followed up with respect to rehospitalization until 31 December 2005. The Kaplan–Meier method was used to calculate the mean time to rehospitalization within 1 year after discharge. Risk factors associated with rehospitalization were examined using Cox proportional hazards regression model.

Results: Four hundred and twenty patients were recruited for the study. Two hundred and eleven patients (50.2%) were readmitted, and the mean time to rehospitalization was 231 days (SD = 7). Bipolar depression at index hospitalization, age at onset, and the number of previous hospitalizations were found to be predictors for time to rehospitalization.

Conclusion: Bipolar depression at index hospitalization, the earlier the onset of an affective episode, and a higher number of previous hospitalizations were associated with a shorter time to rehospitalization. Further studies in this field should test risk factors in a prospective study and be conducted in various mental health systems.

Keywords

bipolar I disorder mood-stabilizing agent number of previous hospitalizations rehospitalization

Bipolar I disorder is a complex and chronic brain disease associated with increased health-care costs, decreased productivity and functioning, poor quality of life, and an increased risk of suicide. The goals of treating bipolar disorder include symptomatic remission, full return of psychosocial functioning, and prevention of relapses and recurrences [1].

Bipolar disorder has at least four, and possibly six, dimensions or relatively discrete symptom areas, including hyperactivity, impulsivity, depression–anxiety, psychosis, irritability, and grandiosity [2]. The complex nature of bipolar disorder means that clinicians often use combination therapy to effectively control mood symptoms, to reduce relapse, and to facilitate socio-occupational functioning. Post et al. found in a 1-year naturalistic Stanley Foundation Bipolar Network study that patients are treated with 4.1 different medications [3]. Other naturalistic studies have also suggested that although a small subset of patients do well with maintenance monotherapy for bipolar disorder, most patients clearly do not [4].

Hospitalization is often indicated for patients who are considered to pose a serious risk of harming themselves or others [5]. Rehospitalization is an important event for the patient and their family, often indicating a relapse/recurrence of significant affective symptoms, dangerous or violent behaviour, or deteriorated function that has not responded adequately to outpatient treatment [5]. Previous studies have indicated that the 1 year rehospitalization rate for bipolar disorder ranges from 41% to 60% [6, 7]. Although rehospitalization risk is only one of the important dimensions of the outcome of bipolar disorder, and which depends on many factors other than the symptomatic course of the disorder, rehospitalization is an important event indicating that the clinical symptoms of the illness have reached an intolerable level. Rehospitalization has also been regarded as a sign of failure by the patients, the families, and the psychiatrists. Identification of predictors of rehospitalization is therefore critical in maximizing prevention and optimizing treatment strategies. If these predictors can be recognized early and adequately, their contribution to rehospitalization would diminish. The purpose of the study was therefore to examine the risk factors affecting the time to rehospitalization for Chinese patients with bipolar I disorder in Taiwan.

Methods

This study was conducted at Kai-Suan Psychiatric Hospital, a major psychiatric centre in Taiwan, under naturalistic conditions. The study was approved by the Institutional Review Board and conducted in accordance with the Helsinki Declaration.

Subjects

All inpatients with DSM-IV [8] bipolar I disorder discharged between 1 January 2002 and 31 December 2004 were screened for eligibility. The diagnosis for bipolar disorder was validated by trained psychiatrists using the Mini International Neuropsychiatric Interview [9]. The patients’ clinical status was also monitored using the Clinical Global Impressions–Severity (CGI-S) at least once a week until discharge. Patients who were discharged against medical advice [10] or transferred to another inpatient facility due to physical problems were excluded from the study.

A mood-stabilizing agent is so defined if it is efficacious in the treatment of acute affective symptoms, does not exacerbate manic or mixed symptoms, or has a prophylactic effect on affective symptoms in bipolar disorder [5, 11]. According to this definition, lithium, valproate, carbamazepine, and antipsychotics (typical or atypical) were considered mood-stabilizing agents in the present study. The number of mood-stabilizing agents prescribed at discharge from index hospitalization was categorized as: one mood-stabilizing agent, two mood-stabilizing agents, or three mood-stabilizing agents.

Subjects consisted of those patients who were discharged with CCI-S scores of 1 (very much improved) or 2 (much improved), while receiving one mood-stabilizing agent (n = 53), two mood-stabilizing agents (n = 312) or three mood-stabilizing agents (n = 55).

Follow-up procedures

All subjects were followed up regularly (usually weekly, biweekly, or monthly, depending on clinical conditions) in the Outpatient Department. Lamotrigine (Lamictal; GlaxoSmith-Kline, London, UK) has been available at Kai-Suan Psychiatric Hospital since November 2006. Also, most recommendations regarding the duration of antidepressant treatment in patients with bipolar disorder suggest prompt discontinuation of antidepressants after remission of depression to avoid precipitating manic and hypomanic episodes [12–14]. Antidepressants and lamotrigine were not prescribed for any patients during the follow-up period. No special care or therapy other than routine education and counselling was provided. Subject rehospitalization status was examined within 1 year after discharge, until 31 December 2005.

Statistical analysis

Time to rehospitalization was regarded as the long-term outcome measure [15]. Other factors affecting the likelihood of rehospitalization included gender, family history of first-, second-, or third-degree blood relatives with affective illness, comorbid alcohol abuse and dependence [16, 17], psychotic features, delusions or hallucinations, at index hospitalization [18, 19], episodes (depressive or manic) at index hospitalization [20], age, the number of mood-stabilizing agents prescribed (one, two or three), age at onset of first major affective episode [21, 22], duration of index hospitalization [23], and number of previous hospitalizations [24, 25].

The Kaplan–Meier method was used to calculate the time to rehospitalization and time to loss of follow up within 1 year after discharge. The univariate Cox proportional hazards regression model was used to investigate potential factors that might have increased risk of rehospitalization. Significant factors in univariate analysis were entered into the forward multivariate Cox proportional hazards regression model to identify risk factors. All tests were two-tailed, and significance was defined as an alpha of less than 0.05. Data were analysed with SPSS version 10.0 for Windows (SPSS, Chicago, IL, USA).

Results

Of a total of 518 patients with bipolar I disorder discharged between 1 January 2002 and 31 December 2004, 420 patients (81.1%) were recruited for this study. The mean time to rehospitalization within 1 year after discharge was 231 days (SD = 7), with 211 patients (50.2%) readmitted. The mean time to loss of follow up within 1 year after discharge was 324 days (SD = 5), and the dropout rate was 11.9% (50/420).

Table 1 shows that, according to the univariate Cox proportional hazards regression model, mood episode at index hospitalization, the number of mood-stabilizing agents prescribed, age at onset, or the number of previous hospitalizations are potential factors that may increase risk of rehospitalization.

Table 1.

Possible predictors and hazard ratio on univariate Cox proportional hazards regression

Variable	n	%	Hazard ratio	95%CI	p
Sex
Male	186	44.3	0.683	0.719–1.241	0.683
Female	234	55.7
Married
Yes	169	40.2	0.912	0.692–1.203	0.514
No	251	59.8
Family history of affective illness
Yes	115	27.4	1.281	0.956–1.716	0.097
No	305	72.6
Comorbid alcohol abuse/dependence
Yes	55	13.1	1.027	0.694–1.520	0.894
No	365	86.9
Comorbid psychosis
Yes	219	52.1	0.950	0.725–1.244	0.709
No	201	47.9
Episode at index hospitalization
Depressive	45	10.7	2.000	1.390–2.877	<0.001∗∗
Manic	375	89.3
No. mood-stabilizing agents					0.002∗∗
One (vs three)	53	12.6	0.606	0.375–0.979	0.041∗
Two (vs three)	312	74.3	0.524	0.366–0.751	<0.001∗∗
	Mean	SD
Age (years)	40.8	11.5	0.996	0.984–1.007	0.449
Age at onset of affective episode	25.0	9.2	0.969	0.953–0.986	<0.001∗∗
Years of education	11.0	3.1	0977	0.936–1.019	0.279
Length of stay (days)	65.4	124.8	1.000	0.999–1.001	0.893
No. previous hospitalizations	5.6	5.2	1.064	1.041–1.087	<0.001∗∗

CI, confidence interval. Bold, statistically significant. ∗p < 0.05; ∗∗p < 0.01.

Fifty-three patients (12.6%) received one mood-stabilizing agent, 312 (74.3%) receive two mood-stabilizing agents, and 55 (13.1%) received three mood-stabilizing agents. Mood stabilizer agents prescribed at discharge are listed in Table 2. Figure 1 presents the time to rehospitalization for bipolar I disorder patients versus number of mood-stabilizing agents as determined on the Kaplan–Meier method. The three mood-stabilizing agents group was significantly associated with a shorter time to rehospitalization and a higher rehospitalization rate (χ²=11.10, df = 2, p < 0.01) than the other groups.

Figure 1.

Time to rehospitalization for bipolar I disorder patients taking (—) one mood-stabilizing agent (n = 53, mean time±SD = 235±18 days), (—) two mood-stabilizing agents (n = 312, mean time±SD = 242±8 days), or (—) three mood-stabilizing agents (n = 55, mean time±SD = 169±19 days; log rank = 12.88, df = 2, p < 0.01).

Table 2.

Mood stabilizer agents prescribed at discharge

Treatment	Subjects receiving treatment at discharge (n = 420)
	N	%
One mood-stabilizing agent	53
Carbamazepine	6	11.3
Valproate	12	22.6
Lithium	30	56.6
Antipsychotics	5	9.5
Two mood-stabilizing agents	312
Carbamazepine	29	9.3
Valproate	80	25.6
Lithium	211	67.6
Antipsychotics	305	97.8
Three mood-stabilizing agents	55
Carbamazepine	39	7.1
Valproate	15	27.3
Lithium	49	89.1
Antipsychotics	55	100.0

Table 3 shows that after further analysis of the forward multivariate Cox proportional hazards regression model, episode at index hospitalization, age at onset of affective episode, and number of previous hospitalizations suggest that patients are more likely to be rehospitalized. Other variables did not significantly affect the time to rehospitalization.

Table 3.

Factors affecting time to rehospitalization on forward multivariate Cox proportional hazards regression model within 1 year after discharge

Risk factor	B	Hazard ratio	95.0%CI	p
Episode at index hospitalization	0.657	1.928^†	1.342–2.771	<0.001
Age at onset of affective episode	−0.026	0.974	0.957–0.992	0.004
No. previous hospitalizations	0.049	1.050	1.026–1.075	<0.001

CI, confidence interval. Bold, statistically significant. ^†Harzard ratio (=Exp(B)): ratio of hazard of bipolar depression vs bipolar mania.

Discussion

As determined by the mean time to rehospitalization (231±9 days) and the rehospitalization rate (50.2%) for all patients, it has been suggested that rehospitalization is common among bipolar patients [6, 7, 26]. Patients with depressive episodes at index admission, a younger age at onset, or a greater number of previous hospitalizations are more likely to be readmitted.

In the present study patients diagnosed with bipolar depression (n = 45) at index hospitalization were significantly associated with a shorter time to rehospitalization (Table 1) and a higher rehospitalization rate (77.5% vs 46.9%, p < 0.01) than those with bipolar mania. In addition, 26 of 45 (57.8%) were readmitted due to depressive episodes, and nine of 45 (20%) were readmitted due to bipolar mania during 1 year follow up after discharge (data not shown). One possibility may be that depressive episodes are more likely to re-occur than manic episodes [20, 27, 28]. American Psychiatric Association guidelines state that following remission of a depressive episode, patients may remain at particularly high risk of relapse for a period [5].

In the present study patients with a younger age at illness onset or more frequent previous hospitalizations were more likely to be readmitted, supporting the notion that early onset bipolar disorder is associated with greater severity, sociopathy, a more chronic course, increased frequency of mood switches, resistance to medications and overall poorer outcomes elsewhere [29–32], and that more prior hospitalizations raise the risk of rehospitalization [33]. It has been confirmed that patients who frequently seek psychiatric services manifest a range of recurring and severe psychopathologies that are difficult to treat, leaving these individuals vulnerable to further exacerbations [34, 35].

Patients in the group receiving three mood-stabilizing agents had the shorter time to rehospitalization and a higher rehospitalization rate than patients receiving one or two mood-stabilizing agents, although this patient group did not remain significant after further analysis using the forward multivariate Cox proportional hazards regression model. Patients in the group receiving three mood-stabilizing agents also had an earlier age at onset of affective episode (p < 0.01) and a higher number of previous hospitalizations (p < 0.01) than other groups. One possible explanation is that this patient group may have a greater severity of illness and treatment difficulty, are more susceptible to relapse, and required more complex medications with different mechanisms of action to enhance efficacy [30]. The present findings are consistent with the results from the first year of the Systematic Treatment Enhancement Program for Bipolar Disorder study by Martinez et al., in that a greater number of medications is predictive of poor outcomes [28].

It is also important to note the negative findings, because the variables were selected based on their predictive utility in other studies. First, studies from Western countries have demonstrated that higher rates of alcohol abuse/dependence exist among patients with bipolar disorder. The Epidemiologic Catchment Area study found that approximately 46% of patients with bipolar disorder may meet the diagnostic criteria for alcohol abuse/dependence [36]. Comorbid alcohol use is typically associated with fewer and slower remissions, greater rates of suicide and suicide attempts, and poor outcome [37–39]. When compared to studies from Western countries, the relationship between comorbid alcohol abuse/dependence and rehospitalization was not significant in the present study. Some studies have stated that the rate of alcohol abuse/dependence among Chinese people has been much lower than that reported in Western countries [40–42]. One of the main reasons may be due to the marked sensitivity to alcohol and associated with high levels of acetaldehyde, during alcohol metabolism, which is suggested to be the biological protective factor [42, 43]. Other studies have demonstrated that Chinese patients with bipolar disorders have a lower comorbidity of alcohol abuse/dependence [44, 45]. This may be explained by the fact that the rate of comorbid alcohol abuse/dependence of Chinese patients with bipolar disorder appears to be lower than that of Western bipolar disorder patients. In short, relatively lower rates of alcohol abuse/dependence (13.1%) were found among the present subjects, and this may be a possible reason why alcohol abuse/dependence failed to predict time to rehospitalization. Second, there was no significant difference in time to rehospitalization between those patients with comorbid psychosis and those without. One possible interpretation is that physicians are more likely to use an antipsychotic for bipolar patients with psychosis to achieve symptom reduction and patient stabilization. The present result is consistent with that reported by Patel et al. [46].

The limitations of the present study are similar to those of previous investigations on rehospitalization of psychiatric patients [46–48]. First, the patients were not randomly assigned to the treatment groups. Second, due to patient recall bias, we could not address other potential confounding factors such as number of previous episodes [49–51], treatment adherence [52], adverse life events [53], and level of social support [54] or expressed emotion [55]. Third, continuation of the medication regimen on which the patient was discharged could not be confirmed. A large prospective naturalistic study, however, has found that most agents used in the acute phases of bipolar disorder are similarly used in the maintenance phase of treatment [56]. Fourth, although bipolar depression tends to occur more frequently than bipolar mania, most of the patients with bipolar depression receive the outpatient treatment. Like the major depressive disorder, a low percentage of patients with bipolar depression require hospitalization for their depressive illness [57]. This is the main reason that the vast majority of subjects were manic at index episode (375 vs 45) in the present study. This limits the emphasis placed on the differential importance of mood state upon admission.

Finally, the present study had a relatively small sample size, and all of the subjects were from a single treatment unit. Therefore the results may not be generalizable to other settings. Further studies in this field should test risk factors in a prospective study and be conducted in various mental health systems.

Footnotes

Acknowledgements

This study was supported by funding from the Kai-Suan Psychiatry Hospital in 2006.

References

1. Suppes

Dennehy

Hirschfeld

. The Texas implementation of medication algorithms: update to the algorithms for treatment of bipolar I disorder. J Clin Psychiatry 2005; 66: 870–886.

2. Swann

Janicak

Calabrese

. Structure of mania: depressive, irritable, and psychotic clusters with different retrospectively-assessed course patterns of illness in randomized clinical trial participants. J Affect Disord 2001; 67: 123–132.

3. Post

, Denicoff

, Leverich

, Morbidity in 258 bipolar outpatients followed for 1 year with daily prospective ratings on the NIMH life chart method. J Clin Psychiatry 2003; 64:680–690; quiz 738–689.

4. Levine

Chengappa

Brar

. Psychotropic drug prescription patterns among patients with bipolar I disorder. Bipolar Disord 2000; 2: 120–130.

5. Practice guideline for the treatment of patients with bipolar disorder (revision). Am J Psychiatry 2002; 159:1–50.

6. Goldberg

Harrow

Grossman

. Course and outcome in bipolar affective disorder: a longitudinal follow-up study. Am J Psychiatry 1995; 152: 379–384.

7. Perlick

Rosenheck

Clarkin

Sirey

Raue

. Symptoms predicting inpatient service use among patients with bipolar affective disorder. Psychiatr Serv 1999; 50: 806–812.

8. American Psychiatric Association. Diagnostic and statistical manual of mental disorders4th edn. Washington, DC: American Psychiatric Association, 1994.

9. Sheehan

, Lecrubier

, Sheehan

, The Mini-International Neuropsychiatric Interview (M.I.N.I.): the development and validation of a structured diagnostic psychiatric interview for DSM-IV and ICD-10. J Clin Psychiatry 1998; 59(Suppl 20):22–33; quiz 34–57.

10.

10. Pages

Russo

Wingerson

Ries

Roy-Byrne

Cowley

. Predictors and outcome of discharge against medical advice from the psychiatric units of a general hospital. Psychiatr Serv 1998; 49: 1187–1192.

11.

11. Bauer

Mitchner

. What is a ‘mood stabilizer’? An evidence-based response. Am J Psychiatry 2004; 161: 3–18.

12.

12. Ghaemi

Lenox

Baldessarini

. Effectiveness and safety of long-term antidepressant treatment in bipolar disorder. J Clin Psychiatry 2001; 62: 565–569.

13.

13. Sachs

Koslow

Ghaemi

. The treatment of bipolar depression. Bipolar Disord 2000; 2: 256–260.

14.

14. Yatham

Kusumakar

Parikh

. Bipolar depression: treatment options. Can J Psychiatry 1997; 42(Suppl 2)87S–91.

15.

15. Lin

Mok

Yatham

. Polytherapy in bipolar disorder. CNS Drugs 2006; 20: 29–42.

16.

16. Strakowski

Keck

Jr McElroy

. Twelve-month outcome after a first hospitalization for affective psychosis. Arch Gen Psychiatry 1998; 55: 49–55.

17.

17. Keck

Jr McElroy

Strakowski

. 12-month outcome of patients with bipolar disorder following hospitalization for a manic or mixed episode. Am J Psychiatry 1998; 155: 646–652.

18.

18. Tohen

Waternaux

Tsuang

. Outcome in mania. A 4-year prospective follow-up of 75 patients utilizing survival analysis. Arch Gen Psychiatry 1990; 47: 1106–1111.

19.

19. Gitlin

Swendsen

Heller

Hammen

. Relapse and impairment in bipolar disorder. Am J Psychiatry 1995; 152: 1635–1640.

20.

20. Perlis

Ostacher

Patel

. Predictors of recurrence in bipolar disorder: primary outcomes from the Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD). Am J Psychiatry 2006; 163: 217–224.

21.

21. Schulze

Muller

Krauss

. Further evidence for age of onset being an indicator for severity in bipolar disorder. J Affect Disord 2002; 68: 343–345.

22.

22. Carter

Mundo

Parikh

Kennedy

. Early age at onset as a risk factor for poor outcome of bipolar disorder. J Psychiatr Res 2003; 37: 297–303.

23.

23. Keck

Jr McElroy

Strakowski

. Outcome and comorbidity in first-compared with multiple-episode mania. J Nerv Ment Dis 1995; 183: 320–324.

24.

24. Harrow

Goldberg

Grossman

Meltzer

. Outcome in manic disorders. A naturalistic follow-up study. Arch Gen Psychiatry 1990; 47: 665–671.

25.

25. O'Connell

Mayo

Flatow

Cuthbertson

O'Brien

. Outcome of bipolar disorder on long-term treatment with lithium. Br J Psychiatry 1991; 159: 123–129.

26.

26. Haywood

Kravitz

Grossman

Cavanaugh

Jr Davis

Lewis

. Predicting the ‘revolving door’ phenomenon among patients with schizophrenic, schizoaffective, and affective disorders. Am J Psychiatry 1995; 152: 856–861.

27.

27. Bromet

Finch

Carlson

. Time to remission and relapse after the first hospital admission in severe bipolar disorder. Soc Psychiatry Psychiatr Epidemiol 2005; 40: 106–113.

28.

28. Martinez

Marangell

Simon

. Baseline predictors of serious adverse events at one year among patients with bipolar disorder in STEP-BD. Psychiatr Serv 2005; 56: 1541–1548.

29.

29. Kessing

Andersen

Mortensen

. Predictors of recurrence in affective disorder. A case register study. J Affect Disord 1998; 49: 101–108.

30.

30. Goodwin

Vieta

. Effective maintenance treatment: breaking the cycle of bipolar disorder. Eur Psychiatry 2005; 20: 365–371.

31.

31. Schurhoff

Bellivier

Jouvent

. Early and late onset bipolar disorders: two different forms of manic-depressive illness?. J Affect Disord 2000; 58: 215–221.

32.

32. Perlis

Miyahara

Marangell

. Long-term implications of early onset in bipolar disorder: data from the first 1000 participants in the systematic treatment enhancement program for bipolar disorder (STEP-BD). Biol Psychiatry 2004; 55: 875–881.

33.

33. Daniels

Kirkby

Hay

Mowry

Jones

. Predictability of rehospitalisation over 5 years for schizophrenia, bipolar disorder and depression. Aust N Z J Psychiatry 1998; 32: 281–286.

34.

34. Swett

. Symptom severity and number of previous psychiatric admissions as predictors of readmission. Psychiatr Serv 1995; 46: 482–485.

35.

35. Bernardo

Forchuk

. Factors associated with readmission to a psychiatric facility. Psychiatr Serv 2001; 52: 1100–1102.

36.

36. Regier

Farmer

Rae

. Comorbidity of mental disorders with alcohol and other drug abuse. Results from the Epidemiologic Catchment Area (ECA) Study. JAMA 1990; 264: 2511–2518.

37.

37. Potash

Kane

Chiu

. Attempted suicide and alcoholism in bipolar disorder: clinical and familial relationships. Am J Psychiatry 2000; 157: 2048–2050.

38.

38. Goldberg

Garno

Leon

Kocsis

Portera

. A history of substance abuse complicates remission from acute mania in bipolar disorder. J Clin Psychiatry 1999; 60: 733–740.

39.

39. Sonne

, Brady

. Substance abuse and bipolar comorbidity. Psychiatr Clin North Am, 1999; 22:609–627, ix.

40.

40. Hwu

Yeh

. Risk factors of alcoholism in Taiwan Chinese: an epidemiological approach. Acta Psychiatr Scand 1990; 82: 295–298.

41.

41. Yang

. The Chinese drinking problem: a review of the literature and its implication in a cross-cultural study. Kaohsiung J Med Sci 2002; 18: 543–550.

42.

42. Chen

Hwu

Yeh

Morimoto

Otsuki

. Aldehyde dehydrogenase deficiency, flush patterns and prevalence of alcoholism: an interethnic comparison. Acta Med Okayama 1991; 45: 409–416.

43.

43. Hahn

Huang

. Acetaldehyde involvement in positive and negative alcohol expectancies in han Chinese persons with alcoholism. Arch Gen Psychiatry 2006; 63: 817–823.

44.

44. Tsai

Chen

Yeh

. Alcohol problems and long-term psychosocial outcome in Chinese patients with bipolar disorder. J Affect Disord 1997; 46: 143–150.

45.

45. Lin

Bai

Yeh

. Substance use disorders among inpatients with bipolar disorder and major depressive disorder in a general hospital. Gen Hosp Psychiatry 1998; 20: 98–101.

46.

46. Patel

Crismon

Pondrom

. Rehospitalization rates of patients with bipolar disorder discharged on a mood stabilizer versus a mood stabilizer plus an atypical or typical antipsychotic. J Behav Health Serv Res 2005; 32: 438–445.

47.

47. Conley

Love

Kelly

Bartko

. Rehospitalization rates of patients recently discharged on a regimen of risperidone or clozapine. Am J Psychiatry 1999; 156: 863–868.

48.

48. Patel

Dorson

Edwards

Mendelson

Crismon

. One-year rehospitalization rates of patients discharged on atypical versus conventional antipsychotics. Psychiatr Serv 2002; 53: 891–893.

49.

49. Kessing

Hansen

Andersen

Angst

. The predictive effect of episodes on the risk of recurrence in depressive and bipolar disorders: a life-long perspective. Acta Psychiatr Scand 2004; 109: 339–344.

50.

50. Tsai

Chen

Kuo

Lee

Strakowski

. 15-year outcome of treated bipolar disorder. J Affect Disord 2001; 63: 215–220.

51.

51. Grof

Duffy

Cavazzoni

. Is response to prophylactic lithium a familial trait?. J Clin Psychiatry 2002; 63: 942–947.

52.

52. Lingam

Scott

. Treatment non-adherence in affective disorders. Acta Psychiatr Scand 2002; 105: 164–172.

53.

53. Johnson

Miller

. Negative life events and time to recovery from episodes of bipolar disorder. J Abnorm Psychol 1997; 106: 449–457.

54.

54. Kent

Fogarty

Yellowlees

. Heavy utilization of inpatient and outpatient services in a public mental health service. Psychiatr Serv 1995; 46: 1254–1257.

55.

55. Butzlaff

Hooley

. Expressed emotion and psychiatric relapse: a meta-analysis. Arch Gen Psychiatry 1998; 55: 547–552.

56.

56. Ghaemi

Hsu

Thase

. Pharmacological treatment patterns at study entry for the first 500 STEP-BD participants. Psychiatr Serv 2006; 57: 660–665.

57.

57. Labbate

Doyle

. Recidivism in major depressive disorder. Psychother Psychosom 1997; 66: 145–149.

Factors Affecting Time to Rehospitalization for Chinese Patients with Bipolar I Disorder in Taiwan

Abstract

Keywords

Methods

Subjects

Follow-up procedures

Statistical analysis

Results

Discussion

Footnotes

Acknowledgements

References