Factors Associated with Age of Onset of Bipolar Affective Disorder from a Tertiary Care Hospital in Southern India: A Cross-sectional Study

Abstract

Introduction: Bipolar Affective Disorder (BPAD), is a chronic debilitating disorder. The mean age at onset for BPAD is observed to be around 20-30 years. The Age at Onset (AO) of BPAD is affected by various factors, including gender, family history, substance use, and other environmental factors. Aim: To assess the AO of BPAD in the clinical population and the relationship of socio-demographic and clinical factors with AO. Materials and Methods: A cross-sectional study, was conducted at Department of Psychiatry, Chettinad Hospital and Research Institute, Kelambakkam, Tamil Nadu, India, from January 2020 to January 2021. The socio-demographic details of total of 53 participants suffering from BPAD attending the tertiary care psychiatric setting were collected. The AO of the sample data and its correlation with gender, family history, substance use, marital status, residential background, etc was analysed by using Statistical Package for the Social Sciences (SPSS) version 22.0. Independent t-test and Analysis of Variance (ANOVA) were applied to compare AO among different variables. Pearson’s correlation and multiple linear regression were applied to assess the correlation. Results: Out of the 53 participants, 30 participants (56.6%) were males and 23 (43.4%) were females of which 31 (58.5%) of the participants had a family history of psychiatric illness. Eighteen (33.8%) had some substance use before onset. No substance use was reported by females. The mean AO of the sample was 24±7.8 years. The mean AO was significantly earlier for, males (t= -2.598; p=0.012), those with a family history of psychiatric illness (t=968; p<0.01) and urban dwellers (t=-3.752; p<0.01). Multiple linear regression analysis showed only family history (B=-3.07, p=0.01) and urban background (B=3.60, p=0.01) significantly predicted earlier AO. AO also negatively correlated with number of suicides per person years of illness (r= -0.387; p<0.01), and number of episodes per person years of illness (r=-0.322, p=0.01). Conclusion: Presence of a family history of psychiatric illness and residing in urban areas showed an overall early prediction of AO rather than gender, and other environmental factors. Earlier AO was associated with worse clinical outcomes of BPAD. Knowledge about AO and its factors might help in predicting treatment outcomes, and in planning primary preventive strategies for vulnerable populations.