Association between undernutrition(as evidenced by low BMI) and mental illness in Lusaka at Chainama Hills Hospital

Abstract

Background Undernutrition in mental illness remains a major problem. However, limited attention has been paid to addressing the problem. In Zambia, there is paucity of information on this subject. This study aimed at establishing the prevalence of undernutrition and determining the association between undernutrition and mental illness, using body mass index (BMI, kg/m²), at Chainama Hills Hospital in Lusaka. The study also investigated socio- demographic factors associated with undernutrition in mental illness. Methods A descriptive cross sectional study based on quantitative approaches involving 412 men and women was conducted at Chainama Hills Hospital. A short questionnaire was administered after obtaining a written informed consent. Patients were examined by the Principle Investigator. The weight (Kg) and height (m) and resulting BMI were measured using a standardized scale, stadiometer and BMI calculator respectively. The diagnosis of mental illness and current medication was obtained from the patient’s medical file as indicated by the attending Psychiatrist. The classification of mental illness is based on the DSM V manual. Bivariate and multivariate analysis with Stata v 13.1was carried out.

Results The prevalence of undernutrition in the study was 29% across all mental illness types seen at the time. The prevalence was higher among patients with Alcohol use disorders (38%). The odds of undernutrition was significantly higher among Alcohol use disorders than any other type of mental illness odds ratio (OR) = 2.7 (P<0.001, 95% CI), adjusted odds ratio (aOR) = 2.5 (P<0.01, 95%CI). The odds of undernutrition was much lower among patients with Convulsive disorder OR= 0.24 (P= 0.04, 95%CI), aOR= 0.28 (P=0.04, 95%CI). After adjusting for socio-demographic factors, the odds were still higher in Alcohol use disorders aOR= 2.1 (P<0.01, 95%CI), and still lower among Convulsive disorders aOR= 0.31 (P=0.06, 95%CI). Factors associated with undernutrition included male gender, low level of education, low social economic status and hospitalization.

Conclusion The prevalence of undernutrition in Mental illness was 29% in this study. Alcohol use disorders were strongly associated with undernutrition while Convulsive disorders were protective. Based on the results of this, treatment of Alcohol use disorders should always include appropriate nutritional supplementation. Anthropometric measurements should be routine for all patients at the hospital. This will reduce morbidity in mental illness due to undernutrition. It is strongly recommended that a policy to regulate the drinking habits and patterns in Zambia be put in place. This should help to reduce avoidable mental illness morbidity due to Alcohol abuse.