Background: Most patients with dementia lose body weight over the course of the disease and have a lower body mass index (BMI) than subjects with normal cognition.
Aims: To examine body mass index and how it correlates with cognitive status, age and gender in patients with different dementia disorders.
Materials and methods: Data from newly diagnosed dementia patients in the Swedish Dementia Quality Registry (SveDem) and recorded information about age, gender, cognitive status and BMI was analyzed using independent samples t tests and one-way analysis of variance.
Results: A total of 12,015 patients, 7,121 females and 4,894 males were included in the study. The average BMI was 24. More than a quarter of the patients had a BMI of <22. Females were significantly older (p < 0.001) and males had a significantly higher BMI (p < 0.001) at the time of diagnosis. BMI differed significantly by gender in various dementia disorders and correlated significantly with cognitive status and age.
Conclusion: At the time of diagnosis, patients with various dementia disorders had a BMI within the normal range. However, a significant number had a BMI in a lower, suboptimal range for older persons stressing the need for nutritional assessment as part of the dementia work up. Further analyses with longitudinal follow-up are needed to investigate BMI changes over time.
Keywords: Alzheimer's disease; Body mass index; Cognitive status; Dementia; Quality registry.