Familial Mediterranean Fever in Spain: Time Trend and Spatial Distribution of the Hospitalizations

Area of Science:

• Rheumatology
• Genetics
• Public Health

Background:

• Familial Mediterranean Fever (FMF) is a rare, hereditary autoinflammatory disorder.
• Understanding FMF hospitalization trends and geographic distribution is crucial for public health planning.

Purpose of the Study:

• To analyze the time trend of FMF hospitalizations in Spain between 2008 and 2015.
• To investigate the geographical distribution of FMF hospitalizations across Spanish provinces.

Main Methods:

• Utilized the Spanish Minimum Basic Data Set at hospital discharge, identifying FMF cases via ICD-9-CM code 277.31.
• Calculated age-specific and age-adjusted hospitalization rates.
• Employed Joinpoint regression for time trend analysis and standardized morbidity ratios (SMR) for geographical risk assessment.

Main Results:

• A total of 960 FMF hospitalizations were recorded from 2008-2015, showing a significant annual increase of 4.9%.
• Thirteen provinces exhibited a higher-than-expected risk of hospitalization (SMR > 1), with five located in the Mediterranean area.
• Fourteen provinces had a lower-than-expected risk (SMR < 1), including three in the Mediterranean region.

Conclusions:

• FMF hospitalizations in Spain demonstrated an increasing trend during the study period.
• Provinces along the Mediterranean coast showed a disproportionately higher risk of FMF hospitalization.
• These findings enhance FMF disease visibility and inform targeted health planning strategies.