BACKGROUND

Chronic inflammation in HIV infection and antiretroviral therapy have been shown to cause balance disorders due to neuromusculoskeletal damage, sensorimotor deficits, failure of foot mechanoreceptors and/or plantar lipoatrophy. However, despite evidence of plantar lipoatrophy in HIV patients, there is a dearth of information on how this relates to walking balance. This study sought to investigate how plantar fat thickness affects dynamic balance in HIV infected persons.

RESEARCH QUESTION

Can plantar lipoatrophy significantly affect walking balance in HIV infected persons?

METHODS

This is a cross sectional study of 367 persons (106 HIV seronegative control subjects, 211 HIV seropositive subjects on antiretroviral therapy (HIV_ART) and 50 HIV ART naïve subjects (HIV_NonART)). Plantar fat thickness (PFT) was measured using diagnostic ultrasound. Subjects were asked to walk at 5 self-selected speeds, from very slow to very fast on a level 15-meter walkway. Average number of steps and time taken to complete the study distance were obtained, used to calculate gait parameters and plot the velocity field diagram for gait analysis.

RESULTS

Findings from this study showed significant reduction in plantar fat thickness, velocity of travel, stride frequency and a significant increase in stride and double support duration (p < 0.01) in HIV-seropositive individuals compared to healthy controls but none were observed between HIV_ART and NonART groups.

CONCLUSION

HIV infection significantly affects dynamic balance and increases the risk of falls, fracture and mobility impairment in this patient population.

SIGNIFICANCE

This study will help clinicians to recognize plantar lipoatrophy as a significant cause of gait pathology in HIV infected persons and thus, make targeted interventions to minimize deformity and impairment, promote functional independence and improve quality of life.