A THREE-MONTH LONGITUDINAL STUDY FOR DIAGNOSTIC STABILITY OF ACUTE AND TRANSIENT PSYCHOTIC DISORDER

The diagnostic category of “acute and transient psychotic disorders” (ATPD) as introduced by ICD-10(F23, WHO 1992) comprises psychotic disorders with features of acute onset (within 2 weeks), presence of typical syndromes that are either polymorphic or schizophrenic or persistently delusional, evidence for associated acute stress and complete recovery in most cases within 2–3 months.1 In creating this category, the authors of ICD-10 took account of a number of concepts for such psychotic disorders,including cycloid psychosis in German psychiatry, bouffée délirante in French psychiatry, psychogenic or reactive psychosis in Scandinavian psychiatry, the remitting schizophrenia in American psychiatry,the atypical psychosis in Japanese psychiatry or acute psychosis of uncertain origin in Indian psychiatry.2 The confirmatory evidence for the validity of this diagnostic entity has come from the international initiatives in the form of WHO multicentered collaborative studies directed primarily at the study of schizophrenia (IPSS)3, first onset psychosis (DOSMeD)4 and Acute Psychoses (CAP)5. Studies of diagnostic stability among patients with the initial diagnosis of ATPD at their first admission have reported modest stabilities spanning over periods of time.6,7


INTRODUCTION
The diagnostic category of "acute and transient psychotic disorders" (ATPD) as introduced by ICD-10(F23, WHO 1992) comprises psychotic disorders with features of acute onset (within 2 weeks), presence of typical syndromes that are either polymorphic or schizophrenic or persistently delusional, evidence for associated acute stress and complete recovery in most cases within 2-3 months. 1 In creating this category, the authors of ICD-10 took account of a number of concepts for such psychotic disorders,including cycloid psychosis in German psychiatry, bouffée délirante in French psychiatry, psychogenic or reactive psychosis in Scandinavian psychiatry, the remitting schizophrenia in American psychiatry,the atypical psychosis in Japanese psychiatry or acute psychosis of uncertain origin in Indian psychiatry. 2 The confirmatory evidence for the validity of this diagnostic entity has come from the international initiatives in the form of WHO multicentered collaborative studies directed primarily at the study of schizophrenia (IPSS) 3 , first onset psychosis (DOSMeD) 4 and Acute Psychoses (CAP) 5 . Studies of diagnostic stability among patients with the initial diagnosis of ATPD at their first admission have reported modest stabilities spanning over periods of time. 6,7 Diagnostic stability, a measure of the degree to which a diagnosis remains the same at the subsequent assessments of the patient implies that the followup diagnosis is the same as the baseline diagnosis, but it does not necessarily mean that the patient is still symptomatic of the disorder at follow-up. There are many factors that lead to diagnostic changes in acute psychosis like poor reliability of assessment, sources of new information (such as informants), longitudinal observation of the symptoms and/or the evolution of the illness. 8 Similarly the psychotic symptoms can be part of schizophrenia spectrum and affective disorders, as well as induced by substance abuse or structural brain lesions; this further underlines the need to verify diagnostic stability following the initial diagnosis of a psychotic disorder. 9 Considering the incidence of ATPD in the clinical setting of Nepal and the need of validating the the diagnosis over a period of time, the current study has tried to explore the socio-demographic correlates of this disorder and short term diagnostic stability over a period of 3 months from their first diagnosis, in a sample of patients from the tertiary care center of Nepal.

METHOD
A total of 75 subsequent drug naïve admissions of either gender in inpatient unit of the Mental Hospital, Lagankhel Nepal, from June to August 2016, aged >=15 years with the initial diagnosis of Acute and Transient Psychotic Disorders (ATPD) were included. The diagnosis of ATPD was made as per the ICD -10 diagnostic criteria at admission and confirmed independently by two consultant Psychiatrists. The patients were enrolled after taking informed consent of their attendants. The socio-demographic profile was collected using a semi structured proforma and the diagnosis was made clinically. Diagnosis of the participants was reviewed at discharge and at follow up visits at 1 and 3 months after the initial diagnosis.

RESULTS
Among 75 patients one patient was taken away from the hospital against medical advice, on the day of admission itself for seeking treatment from faith healers. Additionally, two patients absconded from the hospital on the 3 rd and 9 th day of admission respectively and thus could not be followed up. Hence, 72 out of the 75 patients were either formally discharged upon improvement of their condition or were referred to some other center in case of identification of some underlying organic cause. As seen in Table1 the distribution of male and female were almost equal in the sample with age ranging from 16 to 80 years with a mean age of 30.71 years (SD=14.62 years). Majority of the participants (58.7%) had attained education up to secondary level. Majority (82.7%) of the sample population lived outside of Kathmandu valley indicating the huge area of coverage for service from the center. The mean duration of hospital stay was 14.98 ± 13.95 days with majority (68%) leaving hospital in less than 15 days.
At the time of discharge from the hospital, the diagnosis of ATPD remained the same in 54 out of 72 (75 %) patients. Similarly, at one month follow up, the diagnosis of ATPD remained unchanged in 52 out of 72 (72.2%) patients, whereas at three months follow up 48 out of 72 patients (66.7%) retained the diagnosis of ATPD. However, at the end of three months 5 patients were either referred to neurologists or were lost to follow-up. As depicted in Table 2, three patients were found to be having a demonstrable underlying intracranial pathology giving rise to the psychotic symptoms, hence, their diagnoses was changed to either 'Delirium' (F 5.0) or Other mental disorders due to brain damage and dysfunction and to physical disease (F6.0), depending upon the predominant clinical presentation and were referred for neurological evaluation. At the time of discharge, the diagnosis was changed to Mania in 9 out of 72 (12.5%) cases followed by Schizophrenia in 5 out of 72 (6.94%) cases and to Dissociative Disorder in 1 out of 72 cases (1.38%). At 1 month follow up, the primary diagnosis of ATPD had changed in additional number of patients, including severe depressive episode with psychotic features in 1 out of 72 cases (1.38%) and Alcohol Dependence syndrome with Alcohol induced psychotic disorder in 1 out of 72 cases (1.38%).Similarly, at three months, the diagnosis of one more patient was revised to Cannabis induced psychotic disorder.

DISCUSSION
Mean age of the sample population was 30.71 years which is similar to a study from India 10 and comparable to the mean age of onset of 37.4 years in a study of Scottish Morbidity Record 11 Though the international data suggests that the female are more prone to develop ATPD 12,13 , in our sample we found slight female preponderance like in the study by Mehta et al 14 . The majority of the study participants were from the rural areas (especially outside of Kathmandu valley) which may be because of the fact that this hospital is mostly visited by patients from the lower socioeconomic levels and mostly from the rural regions across the country. The mean duration of stay was 13.85 days and majority of them (68% ) staying less than 15 days is different to the findings from other studies. 15,16 Though the duration of hospital stay is less in ATPD as compared to other psychosis, the duration from our study is lesser. 17 The diagnostic stability of ATPD has been questioned since its inclusion in ICD-10. Castagnini et al. reported that about 50% of the cases with ATPD went on to develop 'schizophrenia and related disorders or affective disorders 12 . In developing countries, however, ATPD has a relatively high diagnostic stability (50-75%). Sajith et al reported that 73% retained the original diagnosis of ATPD after 3 years. 6 Similarly, good diagnostic stability was reported by Thangadurai et al. 18 In a 12-year follow-up study of acute psychosis from the Chandigarh DOSMeD cohort, 1 of the 17 cases developed schizophrenia, none developed affective disorders, and a majority retained the initial diagnosis of acute psychosis. 19 In a short term study of diagnostic stability in South India as well, majority of the patients retained the original diagnosis, showing a good stability of 70.2% and 63.2% at 1 year and 2 year follow up respectively. 10 In a previous Nepalese study also, the diagnosis of ATPD was retained in 80% of the cases at the end of 3 months follow up. 20 In our study as well the original diagnosis of ATPD was retained in more than 65% of the cases at the end of 3 months which indicates a high diagnostic stability. Although the diagnosis of acute psychosis is stable in many cases, some patients may go on to develop schizophrenia or mood disorders (mainly bipolar disorders) over time. It is this group of patients who need to be studied further to identify factors predicting relapse into other disorders. Marneros  The major strength of our study is the reliability of the diagnosis as two consultant psychiatrist were involved in collecting data and making each diagnosis. Similarly, the drop out rate was very less and majority of patients turned up for the follow up. However, there are many limitations of the study. The duration of follow up in our study was just up to 3 months, which is a major limitation as the long term stability and outcome of the patients is still unknown. In addition, factors associated with revision of the initial diagnosis were not explored.

Conclusion
Despite limitations, our study highlights the diagnostic stability of acute and transient psychotic disorder in the Nepalese scenario, with two third of the patients retaining the initial diagnosis at 3 months. Future studies with longer duration of follow ups can shed more light on this topic in our scenario. Exploration of the factors associated with the evolution of ATPD into other psychiatric entities over time in our setting needs to be done.