Key Takeaway
This is one of the strongest natural-history anchors for public FKRP content because it links prevalence and genotype data to concrete respiratory, cardiac, and ambulation outcomes.
Evidence Summary
Epidemiology and natural history in 101 subjects with FKRP-related limb-girdle muscular dystrophy R9. The Norwegian LGMDR9 cohort study (2020)
Large modern natural-history cohort describing prevalence, genotype distribution, ventilatory support patterns, wheelchair use, and sex-associated differences in Norwegian LGMDR9.
cohortNatural HistoryRespiratoryFamilies
Citation: Jensen SM, Müller KI, Mellgren SI, et al. Epidemiology and natural history in 101 subjects with FKRP-related limb-girdle muscular dystrophy R9. The Norwegian LGMDR9 cohort study (2020). Neuromuscul Disord. 2023;33(2):119-132.
Main findings
- The study identified 153 genetically confirmed subjects in Norway, with 101 included in the observational cohort and 88 percent of the total group homozygous for FKRP c.826C>A.
- In one third of cases requiring ventilatory support, respiratory support preceded wheelchair dependency, often because of sleep apnea.
- Female participants showed increased cumulative probability of wheelchair dependency and ventilatory support, while cardiomyopathy correlated positively with male sex in c.826C>A homozygotes.
Practical relevance
- Strong evidence base for explaining why respiratory surveillance cannot wait until loss of ambulation.
- Helps keep natural-history discussions grounded in published cohort data rather than anecdote.
- Useful for clinicians and researchers building monitoring pathways or prioritizing trial-ready outcome measures.
Limitations and cautions
- The cohort reflects a country with a strong founder effect, so prevalence and genotype distribution are not automatically transferable to every setting.
- Observational natural-history data support surveillance planning but do not establish treatment efficacy.
- Some participants overlapped with prior Norwegian work and registry-based recruitment.
Primary Sources
Direct links for verification
Primary indexed record for the paper summary on this page.
Publisher DOI landing page.
Related Content
Related routes inside the site
Study Record
Norwegian LGMDR9 Cohort Study
Published observational cohort describing prevalence, genotype distribution, ventilatory support, and cardiomyopathy patterns in a large Norwegian FKRP population.
Guide
Clinical Features
FKRP-related disease can involve skeletal muscle, motor development, cardiac function, respiratory function, and in some severe congenital presentations, broader neurologic or structural findings. The pattern is variable, which is why the site treats phenotype as a spectrum.
Guide
Monitoring and Care
FKRP-related disease is usually managed through a multidisciplinary model. Monitoring is not only about neurology. Cardiology, pulmonology, sleep evaluation, rehabilitation, genetics, and practical family coordination all matter to safe long-term care.