Higher body mass index is associated with lower foot health in patients with rheumatoid arthritis: baseline results of the Amsterdam-Foot cohort

The prevalence of foot health problems in people living with a rheumatic condition: a cross-sectional observational epidemiological study

This study aimed to determine the prevalence of foot health problems in people living with any rheumatic condition and explore potential associations with exposure variables. A cross-sectional observational epidemiological design was applied. The participants were recruited from one regional patient association in southwest Finland. The data were collected in January-February 2019 and included the Self-reported Foot Health Assessment Instrument (S-FHAI) and demographic questions. In total, 495 responses were obtained. Overall, participants had many foot problems. The point prevalence of self-reported foot problems was 99 per 100 people living with a rheumatic condition. The most prevalent problems were foot pain (73%), dry soles (68%), thickened toenails (58%) and cold feet (57%). Lower educational attainment, increased amount of daily standing and accessing medical or nursing care for foot problems were associated with poorer foot health. The results reveal a high frequency of foot pain among people with rheumatic conditions. The study highlighted the importance of person-centred care and the biological focus that underpins and impacts foot health (what we understand, what we do, and our health-seeking behaviour). Interventions to promote biopsychosocial approaches to personalised foot care could advance people's readiness, knowledge and skill to care for their own feet.

Foot self-care competence reported by patients with rheumatoid arthritis: a cross-sectional study

BACKGROUND

Foot self-care is important for preventing foot problems and maintaining one's foot health. Foot self-care requires competence to identify foot problems, knowledge and skills to care for those problems, and a willing attitude to care for one's foot health. However, there is major gap in the research evidence of foot self-care competence among patients with rheumatoid arthritis. This study aimed to analyse self-reported levels of competence in foot self-care among patients with rheumatoid arthritis.

METHODS

A cross-sectional study design was used. Data were collected using a survey consisting of a self-reported competence in foot self-care competence scale (response options on 5-point Likert scale, higher values indicate higher competence) and background questions. The data were analysed with descriptive and inferential statistics and the psychometric properties of the scale using Rasch analysis.

RESULTS

The participants' (n = 251) self-reported level of competence in foot self-care was moderate (mean 3.50, standard deviation [SD], 0.66). On the sum variable level, the highest mean score was for attitude towards foot self-care (3.98; SD, 0.69), followed by foot self-care knowledge (3.45; SD, 0.67) and experience providing foot self-care (3.38; SD, 0.69). Higher self-reported foot self-care knowledge and female sex were associated with higher self-reported competence in every sum variable.

CONCLUSIONS

Patients with rheumatoid arthritis evaluated their level of competence in foot self-care as moderate and some deficiencies were identified. These results indicate the importance of educating patients with rheumatoid arthritis about how to advance their foot self-care skills and knowledge. In the future, patients with rheumatoid arthritis could benefit from interventions that increase their knowledge of foot self-care together with practical examples, such as online videos, that demonstrate the practical conduct of foot self-care skills in daily life.

Predicting Forefoot-Orthosis Interactions in Rheumatoid Arthritis Using Computational Modelling

Foot orthoses are prescribed to reduce forefoot plantar pressures and pain in people with rheumatoid arthritis. Computational modelling can assess how the orthoses affect internal tissue stresses, but previous studies have focused on a single healthy individual. This study aimed to ascertain whether simplified forefoot models would produce differing biomechanical predictions at the orthotic interface between people with rheumatoid arthritis of varying severity, and in comparison to a healthy control. The forefoot models were developed from magnetic resonance data of 13 participants with rheumatoid arthritis and one healthy individual. Measurements of bony morphology and soft tissue thickness were taken to assess deformity. These were compared to model predictions (99th% shear strain and plantar pressure, max. pressure gradient, volume of soft tissue over 10% shear strain), alongside clinical data including body mass index and Leeds Foot Impact Scale–Impairment/Footwear score (LFIS-IF). The predicted pressure and shear strain for the healthy participant fell at the lower end of the rheumatoid models’ range. Medial first metatarsal head curvature moderately correlated to all model predicted outcomes (0.529 < r < 0.574, 0.040 < p < 0.063). BMI strongly correlated to all model predictions except pressure gradients (0.600 < r < 0.652, p < 0.05). There were no apparent relationships between model predictions and instances of bursae, erosion and synovial hypertrophy or LFIS-IF score. The forefoot models produced differing biomechanical predictions between a healthy individual and participants with rheumatoid arthritis, and between individuals with rheumatoid arthritis. Models capable of predicting subject specific biomechanical orthotic interactions could be used in the future to inform more personalised devices to protect skin and soft tissue health. While the model results did not clearly correlate with all clinical measures, there was a wide range in model predictions and morphological measures across the participants. Thus, the need for assessment of foot orthoses across a population, rather than for one individual, is clear.

Pedobarographic Measurements of Rheumatoid Feet Compared with Clinical Parameters

Objective:

This study aimed to investigate the relationship between plantar pressure pedobarographic measurements and disease activity, radiological abnormalities, and foot indexes in patients with rheumatoid arthritis (RA).

Methods:

Sociodemographics, foot symptoms, anatomical distribution, pain intensity and duration, and podiatry services access data were collected. Disease activity scale of 28 joints (DAS28) was used for the disease activity, and Health Assessment Questionnaire (HAQ) was used for the functional status. Foot function index (FFI) was used to measure the impact of foot pathology on its function. The Modified Larsen scoring was used to assess radiological abnormalities. Pedobarographic measurements were used to analyze foot loading characteristics.

Results:

A total of 104 feet of 52 patients with RA was evaluated. DAS28 scores did not correlate with the plantar pressure values (p>0.05). A significant correlation was found between HAQ scores and right medial midfoot loading pressure (r=0.355; p<0.01). FFI scores were positively correlated with right lateral midfoot loading pressure (r=0.302; p<0.05). No relationship was found between Manchester Foot Pain and Disability Index and plantar loading characteristics. The radiological scores were correlated with left lateral hindfoot plantar pressure (r=0.286; p<0.05).

Conclusions:

Pedobarographic measurements can be considered as a follow-up evaluation tool for the evaluation of all foot parts (forefoot, midfoot, and hindfoot). Rheumatoid feet investigation showed that foot involvement is independent of the disease duration, whereas midfoot plantar pressures are associated with the body mass index. Additionally, DAS28 may fall short as a marker of disease activity because it neglects foot problems.

Reporting of Research Ethics in Studies Focusing on Foot Health in Patients with Rheumatoid Arthritis - A Systematic Review

Research ethics is a fundamental part of the entire research. Patients with rheumatoid arthritis are sensitive group of research participants because their long-term health problems cause significant changes in their foot health. In foot health research, data are usually collected through a clinical assessment of the foot or questionnaires. However, there is limited evidence of the reported research ethics of empirical studies on foot health in patients with rheumatoid arthritis. Therefore this review aimed to analyze the reported research ethics of peer-reviewed empirical studies focusing on foot health in patients with rheumatoid arthritis as research participants. This systematic review used the Medline/PubMed, CINAHL, and Embase databases. A total of 1,653 records were identified, and 32 articles were included in the final analysis. Reporting research ethics in studies of patients with rheumatoid arthritis is fragmented, focusing predominantly on ethical approval and informed consent and lacking a broader discussion about research ethics.