In 2016 a survey was conducted among Korean ALD patients and their families. This page presents the aggregate results.
The data are ten years old. They do not describe the current Korean patient population, and should be read only as a cross-section of that time. They are published here because this survey remains very nearly the only numerical description of the Korean ALD patient population in existence.
Read the limits first
Before the numbers.
- 49 responses in total. All but one were collected in 2016.
- Self-reported. Not verified against medical records.
- The unit is the response, not the patient. In some cases several family members were recorded together in one response.
- “Phenotype at diagnosis” and “current status” describe different points in time.
- 13 of the 49 responses contain internal contradictions or entry errors and are flagged for review.
- Items with heavy missingness — sex (73% missing) and comorbidities (80% missing) — have been excluded entirely.
- Where a cell count is small, the exact number is withheld to prevent re-identification.
These are not prevalence or incidence figures. They describe the distribution among people who answered a survey.
Number of responses
| n | |
|---|---|
| Total responses | 49 |
| Collected in 2016 | 48 |
| Added later | fewer than 5 |
Phenotype at diagnosis
As classified by the respondent at the time of diagnosis.
| Phenotype | n |
|---|---|
| Cerebral ALD | 16 |
| Asymptomatic | 16 |
| Addison-only (adrenal insufficiency alone) | 7 |
| Adrenomyeloneuropathy (AMN) | 6 |
| Other | fewer than 5 |
Asymptomatic individuals — 16 — equal the number with cerebral disease. These are largely people identified through testing after a relative was diagnosed. Family screening is evidently finding a substantial share of the Korean patient population.
Status at the time of the survey
Multiple selections were permitted, so the total exceeds the number of respondents.
| Status | n |
|---|---|
| Spinal cord symptoms | 20 |
| Adrenal insufficiency | 18 |
| Asymptomatic | 18 |
| Cerebral involvement | 16 |
Adrenal insufficiency in 18 of 49 — more than a third. This is a direct measure of how common the most easily missed complication of ALD is in this population.
Six respondents had been classified as AMN at diagnosis, while 20 reported spinal cord symptoms at the time of the survey. The difference reflects people who developed those symptoms over the intervening years.
Lorenzo’s oil
| n | |
|---|---|
| Taking | 22 |
| Not taking | 27 |
About 45% of respondents were taking Lorenzo’s oil.
Lorenzo’s oil lowers plasma very long chain fatty acid levels, but current international recommendations state that the evidence it modifies the course of the disease is insufficient. → Diet · Treatment
Who completed the survey
| Respondent | n |
|---|---|
| Caregiver | 34 |
| Patient | 13 |
| Not stated | fewer than 5 |
More than two thirds were completed by caregivers. This reflects both the age distribution of the disease and the fact that, even for adult patients, it is often a family member who goes looking for information.
How these figures were prepared for publication
- Only aggregate counts are published. Response-level data are not.
- Counts below 5 are withheld. In a disease this rare, small numbers can identify individuals.
- Names, dates of birth, hospitals, treating physicians and free-text answers are not published.
- Items with missingness too high to interpret were excluded.
Registered ALD patients in Korea
Separately from the survey above, one figure is available: the number of people registered as having ALD under Korea’s special co-payment programme for rare diseases, part of the national health insurance system.
| Count | |
|---|---|
| Active registrations | 138 |
| Male | 117 |
| Female | 21 |
As of 1 September 2026.
How to read this number
It is a registration count, not a patient count. Registration is applied for by the patient or family. People who have been diagnosed but never registered, and those whose registration lapsed without renewal, are not in this figure. The true number of patients is higher.
It says nothing about condition. Whether a person has cerebral ALD or AMN, and how far it has progressed, cannot be read from this. The count counts people.
The figure of 21 women is almost certainly an undercount. ABCD1 is on the X chromosome, so there is no reason for women carrying a variant to be fewer than men. That registrations stand at one sixth of the male figure most likely reflects that symptoms in women begin slowly after middle age and are frequently attributed to something else — so many are never diagnosed at all. → Women with ALD
It still matters. Until now there has been no figure at all for the size of the Korean ALD population. When the question “are there patients in Korea?” comes up — in attracting a clinical trial, or in arguing for newborn screening — there is now a number to answer with.
Why this needs to be done again
These data are from 2016. Since then the international consensus recommendations have been revised, the treatment landscape has changed, and the patient population itself will have changed.
The registration count above gives a figure for how many. But no one knows what condition those 138 people are in. Without that, it is difficult to argue for policy change, to attract clinical trials, or to make a case for the support patients need.
This page summarises survey results and is not suitable as a basis for clinical decisions.
Last reviewed: 3 November 2026