We have posted previously about the higher prevalence of obesity and overweight in people with learning disabilities. The researchers in this study were interested in looking at the data on body weight status and lipids levels of adults with learning disabilities who also had mental health problems.
They carried out a stepwise multiple regression analysis, a statistical procedure which enables correlations between potentially predictive variables to be identified. They did this to predict Body Mass Index (BMI) so that they could assess the extent to which any predictor variable was associated with BMI over and above any other predictors.
The researchers identified patients with learning disabilities and psychiatric illness in the target service and collected data on BMI, age, gender, presence of additional physical conditions, residential status, mental illness and use of psychotropic medication.
They then analysed the lipid profile of this group, including serum cholesterol, low-density lipoprotein, high-density lipoprotein (HDL), triglycerides and serum cholesterol/HDL ratio. Triglyceride testing measures triglyceride fat levels in the blood and is usually carried out at the same time ass cholesterol testing as part of a lipid profile to help evaluate risk factors for coronary heart disease. Abnormally high levels may be due to a range of factors, among which are overweight or obesity
They found that 28% of participants were overweight and 41% obese. The majority of obese patients in the study were men with mild learning disabilities.
They found that level of learning disability, gender and level of serum triglycerides were significant predictors in their regression model. However, there were no significant differences in the mean serum cholesterol levels or the mean triglyceride levels between people who were taking or not taking first-generation antipsychotics, second-generation antipsychotics or anti-epileptic medication.
The authors state that the rate of obesity found in the sample was higher than that found in previous studies. They conclude that predictors most likely to be predictive of BMI were level of learning disability, gender and serum triglyceride levels.
The overweight: obesity and plasma lipids in adults with intellectual disability and mental illness, Gazizova, D et al., in Journal of Intellectual Disability Research, 56: 895–901.