Categorisation of foot complaints in systemic lupus erythematosus (SLE) from a New Zealand cohort

Incidence and prevalence of systemic lupus erythematosus in New Zealand from the national administrative datasets

OBJECTIVES

This study aims to provide updated data on the incidence and prevalence of systemic lupus erythematosus (SLE) in New Zealand and to examine the difference between ethnic groups.

METHODS

We identified the SLE cases from the national administrative datasets. The date of first identification of SLE was the earliest date of a related inpatient event or the earliest date of a related outpatient event. The crude incidence and prevalence of SLE in 2010-2021 were estimated by gender, age group and ethnicity. The WHO (World Health Organization) age-standardised rate (ASR) of incidence and prevalence of SLE was calculated, after stratifying the cases by ethnicity and gender.

RESULTS

The average ASR of incidence and prevalence of SLE in 2010-2021 was 2.1 and 42.1 per 100,000 people in New Zealand. The average ASR of incidence for women was 3.4 per 100,000 for women and 0.6 for men. It was highest for Pacific women (9.8), followed by Asian women (5.3) and Māori women (3.6), and was lowest for Europeans/Others (2.1). The average ASR of prevalence was 65.2 per 100,000 for women and 8.5 for men. It was highest for Pacific women (176.2), followed by Māori women (83.7) and Asian women (72.2), and was lowest for Europeans/Others (48.5). The ASR of prevalence of SLE has been increasing slightly over time: from 60.2 in 2010 to 66.1 per 100,000 in 2021 for women and from 7.6 in 2010 to 8.8 per 100,000 in 2021 for men.

CONCLUSION

The incidence and prevalence of SLE in New Zealand were comparable to the rates in European countries. Pacific people had the highest incidence and prevalence of SLE, more than three times the rates for Europeans/others. The high incidence of SLE in Māori and Asian people also has implications for the future as these populations increase as a proportion to the total population.

Effectiveness of custom-made functional foot orthoses versus flat cushioning insoles on pain in patients with systemic lupus erythematosus

OBJECTIVE

To determine the effect of foot orthoses on pain, disability and foot functionality in patients with Systemic Lupus Erythematosus.

DESIGN

Randomized clinical trial.

SETTING

University Podiatric Clinical Area.

SUBJECTS

Patients with systemic lupus erythematosus.

INTERVENTIONS

Patients were randomly assigned to either group A, which received custom-made functional foot orthoses, or group B, which received flat cushioning insoles, for three months.

MAIN MEASURES

The primary outcome was foot pain, measured by 11-point numeric pain rating scale. Foot functionality and foot-related disability were evaluated using the foot function index, the Manchester foot pain and disability, at the beginning and at days 90.

RESULTS

Sixty-six participants (age 47.3 ± 11.9 years) suffering from foot pain, received either the custom-made foot orthoses (N = 33) or the flat cushioning insoles (N = 33). For the analysis of the data, only participants who had finished the follow-up period (90 days) were included. None statistically significant difference between groups were found. In group A, all variables showed statistically significant differences when comparing the initial and final measurements. Pain showed 6.8 ± 1.6 and 4.2 ± 2.9 in group A, at baseline and at 90 days, respectively, group B showed 6.5 ± 1.5 and 4.7 ± 3.0 at baseline and at 90 days, respectively.

CONCLUSION

Both groups showed a reduction in foot pain. This study suggests that not only controlling the foot function, but providing cushioning to the foot, may have positive effects to manage foot pain in patients with systemic lupus erythematosus.