Body Mass Index, Falls, and Hip Fractures Among Nursing Home Residents.

Background: To examine the association between body mass index (BMI) and the risk for falls and hip fractures among nursing home (NH) residents.

Methods: A cohort study of newly admitted NH residents, excluding those with a prior history of hip fracture. Using the Minimum Data Set 2.0 (2006-2010), we determined the occurrence of new falls and hip fractures among NH residents during their first 3 months of stay. Residents were categorized as underweight (BMI < 18.5), normal-to-overweight (18.5 ≤ BMI < 30), mildly obese (30 ≤ BMI < 35), and moderately-to-severely obese (BMI ≥ 35).

Results: Among newly admitted NH residents over the first 3 months, 51.1% of underweight residents, 53.1% of normal-to-overweight residents, 49.1% of residents with mild obesity, and 43.1% of residents with moderate-to-severe obesity experienced a fall; 3.1% of underweight residents, 2.5% of normal-to-overweight residents, 1.5% of residents with mild obesity, and 1.1% of residents with moderate-to-severe obesity experienced a hip fracture. In comparison with normal-to-overweight residents, after adjustment for resident-level and facility-level characteristics, mildly obese residents (odds ratio [OR] = 0.94, 95% confidence interval [CI] = [0.91-0.93]), and moderately-to-severely obese residents (OR = 0.84 [95% CI = 0.83-0.85]) were less likely to experience a fall; Mildly obese residents (OR = 0.65 [95% CI = 0.63-0.68]), and moderately-to-severely obese residents (OR = 0.84 [95% CI = 0.83-0.85]) were less likely, and underweight residents were more likely (OR = 1.22 [95% CI = 1.18-1.26]) to experience a hip fracture.

Conclusion: Obesity is associated with reduced risks for falls and hip fractures among newly admitted NH residents. Future studies are needed to explore possible explanations for these associations.