Background Obesity and foot problems are common in older adults and associated with many negative health outcomes. Better understanding of the consequences of patterns of weight change may lead to better prediction and dealing with foot pain and foot disorders.

Objectives This study identified longitudinal trajectories of weight in a population-based study and examined the association of these groups with current foot problems.

Methods We used 28 measures of weight over 57 years to identify trajectories of weight in 2445 members of the Framingham Foot Study using k-means longitudinal cluster analysis. Foot examinations (2002–2008) recorded presence of foot pain, hallux valgus, claw toes, hammer toes and overlapping toes on each foot. Associations between weight group membership and foot problems at time of foot exam, adjusted for age and sex, were examined using logistic regression with generalized estimating equation correction for two feet per subject. The reference group used for analysis was the group with the lowest weight trajectory (“E”).

Results We found 5 trajectories of weight, representing relatively constant patterns over time, with weight increasing from groups E to A. Those in group “E” were more likely to be older, while the youngest were in group “A” group. “E” had the lowest prevalence of foot pain (14%) while group “A” had the highest (22%). Similarly, group “A” had the lowest prevalence of hallux valgus, while group “E” had the highest (36%) (Table 1).

Compared to group “E”, other groups were more likely to have foot pain (ORs 1.57–3.50, Table 2) and less likely to have hallux valgus (ORs 0.73–0.99). For claw toes, all but one group were more likely to have claw toes compared to group “E”. Groups “A” and “D” were more likely to have hammer toes (ORs 2.40 and 1.35, respectively) compared to group “E”. We found no associations between overlapping toes and group membership.

Conclusions Trajectories with higher weight over a lifetime had increased odds of foot pain and claw toes, and decreased odds of hallux valgus later in life. These results provide evidence that having lower weight over one's lifetime can reduce the likelihood of foot problems later in life.

Disclosure of Interest None declared