Prevalence and factors associated with the presence of nonalcoholic fatty liver disease in an adult population in Spain.
OBJECTIVE
The prevalence of nonalcoholic fatty liver disease (NAFLD) is unknown in Spain. The purpose of detecting NAFLD patients is to determine the associated factors and prevent its evolution to more severe forms. The aim of this study is to determine the prevalence and factors associated with NAFLD.


METHODS
This is a multicentre, cross-sectional, populational study. Individuals between 15 and 85 years of age were randomly selected from 25 primary healthcare centres in the province of Barcelona, Spain. Clinical histories were reviewed, and anamnesis, physical examination, blood analysis and hepatic echography were performed. Individuals with an alcohol intake greater than 30 g/day in men and greater than 20 g/day in women or with known liver disease were excluded.


RESULTS
Seven hundred and sixty-six individuals with a mean age of 53+/-14 years (range 17-83, 42.2% men) were included in the study. One hundred and ninety-eight individuals presented NAFLD with echographic criteria (prevalence 25.8, 33.4% men and 20.3% women P<0.001). On multivariate analysis, the following were associated with NAFLD: male sex [odds ratio (OR): 2.34, 95% confidence interval (95% CI): 1.57-3.49], age (OR: 1.04 per year, 95% CI: 1.02-1.05), metabolic syndrome (OR: 2.19, 95% CI: 1.29-3.72), insulin resistance (OR: 6.00, 95% CI: 3.43-10.5) and alanine aminotransferase (OR: 4.21, 95% CI: 2.23-7.95). Of the individuals who consumed alcohol, 29.4% consumed alcohol within the inclusion criteria, with a mean of 9.17+/-6.75 standard beverage units per week. Moderate alcohol intake was not related to NAFLD, although a possible protector effect was found with the quantity consumed among the drinkers who did not consume excessive amounts of alcohol (OR: 0.93 per standard beverage units, 95% CI: 0.88-0.98).


CONCLUSIONS
NAFLD prevalence in our population is very high. Male sex, age, metabolic syndrome, insulin resistance and alanine aminotransferase are the factors associated with NAFLD. Furthermore, studies should be carried out with respect to the controversial effect of alcohol on NAFLD.
Caballería
Llorenç
L
Primary Healthcare Centre Premià de Mar, Primary Healthcare Research Support Unit Metropolitana Nord. IDIAP Jordi Gol, Barcelona, Spain. lcaballeria.bnm.ics@gencat.net
Pera
Guillem
G
Auladell
Maria Antònia
MA
Torán
Pere
P
Muñoz
Laura
L
Miranda
Dolores
D
Alumà
Alba
A
Casas
José Dario
JD
Sánchez
Carmen
C
Gil
Dolors
D
Aubà
Josep
J
Tibau
Albert
A
Canut
Santiago
S
Bernad
Jesús
J
Aizpurua
Miren Maite
MM
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000410:Alanine Transaminase / Q000097:blood; D000428:Alcohol Drinking / Q000009:adverse effects / Q000453:epidemiology; D004812:Epidemiologic Methods; D005234:Fatty Liver / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000453:epidemiology; D007333:Insulin Resistance; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications / Q000453:epidemiology; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000453:epidemiology; D012737:Sex Factors; D013030:Spain / Q000453:epidemiology; D055815:Young Adult
D000410:Alanine Transaminase