A researcher discovered the high prevalence of long chain fatty acid oxidation disorders (LCFAODs) and other metabolic diseases in indigenous populations of New Zealand and analyzed how the local health care system adapted to this reality.

The publication conducted by Callum focused on Māori and Pacific indigenous populations, which constitute 25% in the country. Inborn errors are especially common in these communities, inducing tools and systems to better screen, follow, treat and support such pathologies.

An abnormally high prevalence of fatty acid oxidation disorders in this region compared to Western Europe may have originated as an evolutionary advantage. A diet high in fat and low in carbohydrates is the norm, and disease rates have also been observed in communities with similar diet patterns.


Continue Reading

Although currently admirable, the management of such metabolic disorders has improved over the years. The expanded newborn screening (ENBS) is an important landmark in the progression of medical care in the region. Before this was implemented, such diseases were thought to be uncommon since diagnosis was very rarely made.

Read more about LCFAOD etiology

Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency was also shown to be common in New Zealand. “Large numbers of predominantly Māori and Samoan babies had elevated C14:1 acylcarnitine levels suggesting VLCAD deficiency,” the authors said. Moreover, 30 of 60,000 ENBS turned out positive for VLCAD each year. These high rates are thought to respond to a need to spare glucose and protect against ketosis precipitated by their cultural diet.

Another disease observed was the X-linked peroxisomal disease adrenoleukodystrophy (ALD). In contrast with VLCAD deficiency, this disease is potentially severe. Pedigrees of the Auckland iwi, Ngāti Whātua Ōrākei seem to be affected the most.

A rare case of ALD was reported in a 10-month-old male patient who presented with nonfebrile seizures and motor dysfunction in the right upper limb. Although this disease had never been reported in children younger than 3 years old, local doctors proposed ALD as a differential diagnosis and indicated magnetic resonance imaging (MRI), concluding the diagnosis. Since then, the surveillance program has been modified to begin the protocol of screening MRIs every 6 months at 18 months old.

“The New Zealand metabolic service’s considerable experience with indigenous inborn errors of metabolism illustrates the many differences services can expect with their local populations,” the author concluded.

Reference

Wilson C. Metabolic disease in the pacific: lessons for indigenous populations. J Inherit Metab Dis. Published online March 10, 2022. doi:10.1002/jimd.12495