Assessing how foot problems— namely, pain, neuropathy, and deformity— contribute to frailty syndrome has been a challenge for researchers, as transporting frail elders to lab facilities creates its own set of issues. But a recent study from the University of Arizona used wearable sensors to assess the seniors in their “natural” environment and found significant relationships between the number of foot problems and degree of frailty.
In the study, 128 participants ≥65 years of age, were assessed for foot pain, neuropathy, and deformities. Using self-reported pain measures, researchers identified 2 groups: participants with a score of >4 for moderate-to-severe pain and those with a score of ≤4 for absent-to-no pain. Presence of neuropathy was determined by inability to perceive touch or vibration using standardized tests. Presence of deformity, including bunion, hammertoe, and flatfoot, was determined after visual foot inspection of both feet; categorization was based on presence of 1 condition on either foot. Of 117 participants in the analysis set:
- 19% had moderate-to-severe foot pain
- 42% had neuropathy
- 51% had at least 1 deformity
- 77% had foot pain, neuropathy, or a deformity, with 26% having 2 or more problems
Frailty was assessed using 5 measures (weight loss, weakness, walking speed, exhaustion, and low energy expenditure) and an algorithm was created to categorize participants into 3 groups: nonfrail (35%), prefrail (48%), and frail (20%). Participants self-reported falls in the previous 6 months and kept a fall diary during the 6 months of the study. In-home assessments were conducted using 5 small inertial sensors attached above the ankles and knees and at the lower back to assess balance, gait, and physical activity.
There were significant differences in age, use of a cane or walker, and Falls Efficacy Scale score for participants with a foot problem. Although most of the participants were women, there were no significant differences in who had a foot problem based on sex, race or ethnicity, body-mass index category, percentage of body fat, or percentage of muscle. The authors did observe a significant trend of increasing foot pain with increasing body-mass index (P=.048); they also noted that those with foot pain had a significantly higher mean percentage of body fat.
Compared to the nonfrail group, the prefrail group had a 2-fold increase in odds of having a foot problem; for the frail group, the increase was several-fold and achieved statistical significance for having 2 or more foot problems, foot pain, and peripheral neuropathy. Weakness and exhaustion both had an odds ratio of ≥4.
As might be expected, concerns about falling increased with having a foot problem, particularly for those with foot pain, neuropathy, foot deformity, or 2 or more foot problems. Interestingly, 38% of participants reported a fall during the study period.
Compared to the group with no foot problems, sensor readings revealed significantly lower gait speed, shorter stride length, and longer time in double support for participants with foot pain, neuropathy, or 2 or more foot problems.
According to the authors, their findings reveal a need to assess community-dwelling older patients for specific foot problems and use interventions that support strength, power, balance, and function to prevent deconditioning that can lead to frailty.
Muchna A, Najafi B, Wendel CS, Schwenk M, Armstrong DG, Mohler J. Foot problems in older adults. Associations with incident falls, frailty syndrome, and sensor-derived gait, balance, and physical activity measures. J Amer Podiatr Med Assoc. 2018;108(2):126-139.