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The Declining Incidence of Legg-Calve-Perthes' Disease in Northern Ireland: An Epidemiological Study
Conor J Mullan1, Lara J Thompson, Aidan P Cosgrove
1Royal Belfast Hospital for Sick Children (RBHSC), Belfast, UK.
Insights
Incidence of Legg-Calve-Perthes disease (LCPD) in children aged 0-14 in Northern Ireland decreased by 61% over 15 years. Environmental factors likely contribute to this decline in pediatric LCPD cases.
Area of Science:
- Pediatric Orthopedics
- Epidemiology
- Public Health
Background:
- Legg-Calve-Perthes disease (LCPD) is an idiopathic condition affecting the pediatric femoral head, with poorly understood causes and significant long-term hip pathology.
- Previous research indicated geographical variations in LCPD incidence, with Northern Ireland (NI) showing relatively high rates.
- A declining trend in new LCPD diagnoses over time has been observed.
Purpose of the Study:
- To investigate changes in the incidence of Legg-Calve-Perthes disease (LCPD) within the pediatric population (0-14 years) in Northern Ireland over a 15-year period.
- To analyze epidemiological trends and potential contributing environmental factors for LCPD.
- To update understanding of LCPD prevalence in a specific geographical region.
Main Methods:
- A retrospective cohort study design was employed (Level IV evidence).
- Data from an established database of pediatric LCPD cases (ages 0-14) were collated and confirmed with electronic radiologic records.
- Postal code data were used as a proxy for socioeconomic deprivation to assess geographical associations.
Main Results:
- A significant 61% decrease in LCPD incidence was observed in the pediatric population of NI over the 15-year study period.
- No significant changes were found in the age or sex distribution between the two cohorts analyzed.
- The association between geographical measures of deprivation and LCPD incidence in NI remained evident.
Conclusions:
- The incidence of new Legg-Calve-Perthes disease (LCPD) cases is demonstrably decreasing over time.
- The consistent epidemiological data between cohorts suggest environmental changes are influencing the decline in LCPD.
- Potential environmental factors implicated include changes in smoking rates, breastfeeding practices, lead exposure, and vaccination implementation.
Background:
Legg-Calve-Perthes' disease (LCPD) is an idiopathic disease of the femoral head affecting the pediatric population. The causative factors remains poorly understood and it is associated with significant hip pathology in adult life. Research has demonstrated wide geographical variation in the incidence rates of LCPD with a relatively high incidence occurring in Northern Ireland (NI) shown in a previous study of incidence from the same unit. The number of new diagnoses of LCPD seems to be declining over time. This study aimed to track changes in the incidence of LCPD within the 0- to 14-year-old population over a 15-year period in NI.
Methods:
An established database was utilized to collate information of any individual between the ages of 0 to 14 years with a diagnosis of LCPD. The data were compared with electronic radiologic records to confirm the diagnosis. Postal code data were used to the determine location of residence and used as a proxy measure of deprivation.
Results:
The results of this epidemiological study have demonstrated a 61% decrease in the incidence of LCPD over a 15-year period within the pediatric population of NI. Comparison between 2 cohorts reveals no distinguishable change in distribution of age or sex. The relationship between geographical proxy measures of deprivation in NI and LCPD remains evident.
Conclusions:
The number of new cases of LCPD is decreasing over time. The epidemiological data are unchanged between 2 cohorts over a 15-year period, and this therefore supports a change within the patients' environment relating to this decline. This change could relate to a number of factors including smoking rates, breastfeeding, lead use, and vaccination implementation.
Level Of Evidence:
Level IV-retrospective cohort study.
