Determinants of Low Body Mass Index in Patients with Parkinson's Disease: A Multicenter Case-Control Study

In Parkinson's disease (PD) patients, the factors related to weight loss remain unclear.

To investigate determinants of low body mass index (BMI) in PD patients.

We identified factors associated with low BMI in PD patients in a multicenter case-control study. A total of 435 PD patients and 401 controls were included.

The mean BMI was significantly lower in PD patients than in controls (22.0±3.4 kg/m2 vs. 25.4±4.3 kg/m2), with an adjusted odds ratio (AOR) of 3.072 (95% CI, 2.103-4.488; p < 0.001) for low BMI (<22 kg/m2) in PD. Compared to the high-BMI PD group (>22 kg/m2), the low-BMI PD group (<22 kg/m2) had more women; a longer disease duration; higher revised Movement Disorder Society Unified PD Rating Scale (MDS-UPDRS) II and IV scores; an increased levodopa equivalent dose (LED); and increased constipation, visual hallucination, dysphagia, dyskinesia and wearing off rates. There were no between-group differences in depression, anhedonia, apathy, sleep problems and daytime sleepiness. Multivariable analysis showed that visual hallucination (AOR, 2.408; 95% CI, 1.074-5.399; p = 0.033) and the MDS-UPDRS IV (AOR, 1.155; 95% CI, 1.058-1.260; p = 0.001) contributed to low BMI after controlling for clinical factors. In a second model, visual hallucination (AOR, 2.481; 95% CI, 1.104-5.576; p = 0.028) and dyskinesia (sum of the MDS-UPDRS 4.3-4.6) (AOR, 1.319; 95% CI, 1.043-1.668; p = 0.021) significantly contributed to low BMI.

PD patients were 3 times more likely than healthy controls to have a low BMI. Motor complications, particularly dyskinesia, and visual hallucination were significantly associated with low BMI in PD patients.