Dietary Protein Intake and Falls in Older People: Longitudinal Analyses From the Osteoarthritis Initiative.

Objectives: Literature regarding dietary protein intake and risk of falls is limited to a few studies with relatively small sample sizes and short follow-ups, which have reported contrasting findings. Thus, we investigated whether dietary protein intake is associated with risk of falls in a large cohort of North American adults.

Design: Data were drawn from the Osteoarthritis Initiative, a cohort study, with 8 years of follow-up.

Setting And Participants: Community-dwelling adults with knee osteoarthritis or at high risk for this condition.

Methods: Dietary protein intake was recorded using the Block Brief 2000 food frequency questionnaire and categorized using gender-specific quartiles (Q). Falls were self-reported in response to the question "Did you fall during the past year?" categorized as yes vs no and made during the 6 visits over 8 years of follow-up. Results are reported as relative risks (RRs), with their 95% confidence intervals (CIs), using a multivariable Poisson regression.

Results: The final sample consisted of 4450 adults (mean age 61.2 years, females = 59.6%). Higher dietary protein intake was significantly associated with higher frequency of falls during the year before baseline. After adjusting for 17 potential confounders, people with the greatest amount of protein intake (Q4) had a significantly higher risk of falling over the 8-year follow-up period (RR 1.112, 95% CI 1.027-1.211, P = .009) than those with the lowest protein intake (Q1).

Conclusions/implications: In this cohort of people affected by knee osteoarthritis or at high risk for this condition, high dietary protein intake may increase the risk of falls in older people, but further research is needed to confirm or refute these findings.