Relationship between body weight gain and significant knee, hip, and back pain in older Americans

Objective: To examine the association between BMI (kilograms per meter squared) and reports of significant knee, hip, and back pain using data from a nationally representative sample of U.S. adults 60 years or older. Research Methods and Procedures: Population-based survey data from the Third National Health and Nutrition Examination Survey, involving 5724 adults 60 years or older, were used. BMI. calculated from measured weight (kilograms) and height (meters squared), was used to categorize participants into six BMI-defined groups: underweight (<18.5), desirable weight (18.5 to 24.9), overweight (25 to 29.9), obese class 1 (30 to 34.9), obese class 11 (35 to 39.9), and obese class III (greater than or equal to40). The presence of significant knee, hip. and back pain in the groups was studied. Results: The overall prevalences of knee, hip, and back pain were 21%. 14%, and 22%. respectively. Prevalence estimates for knee (underweight 12.1% to obesity class III 55.7%) hip (underweight 10.4% to obesity class III 23.3%), and back (underweight 20.2% to obesity class III 26.1%) pain increased with increased BMI. Sex-, race-, and age-specific pain prevalence estimates also generally increased at increased levels of BMI. Discussion: Among U.S. adults 60 years or older, the prevalence of significant knee, hip, and back pain increases with increased levels of BMI.