Dietary intake in adults with severe mental illness, receiving outpatient treatment in a Scandinavian clinic

Abstract

Introduction: Life expectancy in severe mental illness (SMI) populations is highly reduced when compared to the general population, and cardiovascular disease (CVD) is the main contributor to premature death. Lifestyle diseases known to increase CVD risk, such as diabetes type 2 and obesity, are prevalent in SMI populations. Common antipsychotics increase the risk of obesity by affecting appetite, and SMI itself affects the ability to maintain a healthy diet. Few studies on diet in this population have been conducted, but unhealthy eating habits have been suggested. Food based dietary guidelines (FBDG) are developed to decrease risk of lifestyle related diseases such as CVDs. In this study, we hypothesized low adherence to the Norwegian FBDGs in an SMI outpatient population. To our knowledge, this is the first study to give a detailed description of dietary habits in a Scandinavian outpatient SMI population. Materials and methods: In this study, we included adult outpatients diagnosed with SMI (schizophrenia-/psychosis-/bipolar affective disorder), treated at Asker District Psychiatric Center, Norway. Adherence to Norwegian FBDG was assessed by a digital food frequency questionnaire (DIGIKOST-FFQ). The FFQ was completed twice, in one-month intervals, subsequent to an initial 24h recall interview providing estimates on calculated nutrient intake. Measurements of body mass index (BMI kg/m2) were performed, and biomarkers relevant to diet and CVD were retrieved. Results: Twenty-five SMI patients were included (male n=13, female n=12). Mean age was 40 years (±SD 13). 44% of the overall population were obese (BMI >30 kg/m2) and mean BMI was 30 kg/m2. Pooled mean diet score was 8.2 (±SD 2.9), corresponding intermediate overall adherence to FBDGs. Overall adherence to FBDGs was low in 47% and 21% in the first and second completion of the FFQ respectively. In both completions >50% reported intakes with low adherence to FBDGs regarding unsalted nuts, processed meats, foods rich in fats and sugars and dietary supplements. This was also true for FBDG regarding fruits and berries as well as drinks with added sugars in the first completion of the DIGIKOST-FFQ. Calculated nutrient intakes was similar to that reported by the general Norwegian population in the NORKOST 3 report. Conclusion: Blood markers related to CVD-risks indicate a need for lifestyle intervention at the least according to ESC/EAS guidelines of 2021. Although more studies including larger study samples should be conducted, this study found poor dietary habits in SMI individuals concerning several FBDGs with known effects on CVD-risk.