Objective
To explore the diets of people living with psychotic disorders, and to compare their dietary composition to the general population.
Method
184 people with psychotic disorders in Adelaide, South Australia completed a food frequency questionnaire. Physical information and mental health status were collected. Outcome measures included energy and macronutrient intake; fish, sodium, fruit and vegetable intake; micro-nutrient intake; body mass index; waist circumference; and diagnoses of diabetes and hypertension. The RDI of nutrients was derived from Australian Government publications. Comparison dietary data was obtained from surveys carried out by the Australian Bureau of Statistics.
Results
The majority of participants were overweight or obese (78%) and 77.5% met the criteria for at-risk waist circumference; and 58% of participants consumed salt and saturated fat in excess of the RDI. Most did not achieve the RDI for fruits and vegetables (97.8%), fibre (88.6%), fish (61.4%), magnesium (73.4%) or folate (86.4%).
Women with psychosis had significantly higher intakes of vitamins and minerals compared to women in the general population. Men and women with psychosis consumed more daily total fat, saturated fat and sodium compared to adults in the Australian population, but lower fibre and vitamin E than their male and female counterparts.
Conclusion
People with psychosis, especially women, report poor dietary choices including increased energy and fat intake, heightening their risk for cardiovascular disease. Women with psychosis report higher intake of vitamins and minerals than women in the general population. Whilst dietary intake contributes to obesity in psychosis, other factors including antipsychotic agents, decreased physical activity and smoking add to the cardiovascular risk.
People with psychosis have a shorter life expectancy than the general population (Laurson, 2011), with cardiovascular morbidity contributing significantly to their poor health outcomes. The risk factors for CVD in psychosis not only include the traditional risk factors of smoking, hypertension, obesity, diabetes, decreased physical activity and dyslipidaemia, but also disease-specific and treatment-related factors. Despite increased prevalence of traditional risk factors, people with a psychotic illness are less likely to be adequately screened (Osborn et al., 2007) or treated, with up to 88% of adults with schizophrenia not receiving recommended therapy for their physical conditions (Nasrallah et al., 2006). Many antipsychotic medications are associated with obesity, diabetes and dyslipidaemia (De Hert et al., 2012). However, people with severe mental illness who are drug naïve still have an elevated relative risk of CVD (Osborn et al., 2007); therefore, other factors must also contribute.
Numerous studies have investigated the association between cardiovascular risk and macro- and micronutrient deficiency or excess. The American Heart Association has published guidelines on diet and lifestyle recommendations to prevent cardiovascular disease (Lichtenstein et al., 2006). A diet high in fibre, fruit and vegetables, and low in saturated fat, trans fat and salt, has been promoted for cardiovascular health. Several small studies have assessed the diet quality in people with psychotic disorders (McCreadie, 2003, Strassnig et al., 2003 and Henderson et al., 2006). However, there have been variations in the study design, such as using dietary recall in the past 24 h (Strassnig et al., 2003) or using a four-day dietary record (Henderson et al., 2006). This suggests that the evidence is inconsistent concerning whether people with psychosis have a poor diet, which would then contribute to the elevated risk of cardiovascular disease in psychosis.
We undertook a cross-sectional study of a population with psychosis in order to clarify their dietary composition. If poor dietary choices contribute to the increased risk of cardiovascular disease, then dietary interventions should be a clinical priority.
