Associations Between Body Mass Index and Foot Joint Pain in Middle‐Aged and Older Women: A Longitudinal Population‐Based Cohort Study

Abstract

ObjectiveTo investigate the relationship between body mass index (BMI) and foot joint pain (FJP) over a 5-year period in a community-based cohort.MethodsWe examined a subset of women from the Chingford Women's Study, a community cohort followed up for 20 years. From a baseline of 1,003 female participants, we reviewed data from 639 women (64%) for whom complete data sets for FJP and BMI were obtained over a 5-year period between year 10 (Y10) and year 15 (Y15). Descriptive statistics, binary regression modeling, and odds ratios (ORs) were used to examine the longitudinal relationship between BMI and FJP.ResultsFor Y10 and Y15, the median age was 61 years (interquartile range [IQR] 57–67) and 66 years (IQR 62–72), respectively, and the mean ± SD BMI was 26.7 ± 4.6 kg/m2 and 27.2 ± 4.8 kg/m2, respectively. FJP prevalence was 21.6% at Y10 and 26.6% at Y15. Longitudinal analyses showed that both BMI and FJP increased significantly from Y10 to Y15 (P < 0.001). The odds of having FJP after a 5-year period increased by 4.9% for each BMI unit increase 5 years earlier (OR 1.049 [95% confidence interval (95% CI) 1.011–1.089], P = 0.012). This remained significant when adjusted for age, diabetes mellitus, and rheumatoid arthritis (OR 1.051 [95% CI 1.011–1.091], P = 0.012).ConclusionThis is the first large longitudinal cohort study demonstrating that, in middle-aged women, a high BMI precedes and is predictive of FJP independent of age. Evidence from our findings can be used to identify those individuals at risk of developing FJP.

Prevalence of Foot Pain Across an International Consortium of Population‐Based Cohorts

“…Previous cross‐sectional studies have also demonstrated associations between increasing BMI and foot pain , in particular fat mass (). There is also evidence from longitudinal studies that BMI is a predictor of incident foot pain over 5 years (), and fat mass is a predictor of incident foot pain over 3 years ().…”

“…We do expect that the prevalence of foot pain is likely high in the US, given that the cohort from Framingham, Massachusetts, has the second highest foot pain prevalence across these cohorts. In addition, high BMI, which is also a factor associated with foot pain (), is more common in the Johnston County Osteoarthritis Project than in other cohorts.…”

The associations of leg lean mass with foot pain, posture and function in the Framingham foot study

“…A similar multinomial analysis was used to determine the association of leg lean mass with foot function (OR for pronatory and supinatory versus the referent). Regression models were first unadjusted for covariates, followed by adjustment for age, and for BMI to account for adiposity, which is associated both with lean mass [38] and with foot pain [39]. Models were further adjusted for sex, and sex-specific models were examined to evaluate whether sex modified the association between leg lean mass and foot pain, posture and function.…”

Fat mass, but not fat-free mass, predicts increased foot pain with obesity, independent of bariatric surgery

“…Elevated BMI has been found to be a predictor of future foot pain over a two-year period in a community cohort [28] and indeed was a predictor of foot joint pain in a study of women over a five-year period [29] . The findings of our study, however, suggest that using the BMI alone may underestimate the impact of adiposity and it may not be a good predictor of future prognosis for bariatric cohorts with foot pain.…”