Incidence and risk factors for non-alcoholic fatty liver disease: A 7-year follow-up study among urban, adult Sri Lankans.

Background This study investigated incidence and risk factors for NAFLD among an adult cohort with 7-year follow-up. Methods The study population (age-stratified random sampling, Ragama MOH area) was screened initially in 2007 (aged 35-64 years) and re-evaluated in 2014 (aged 42-71 years). On both occasions assessed by structured interview, anthropometric measurements, liver ultrasound, biochemical and serological tests. NAFLD was diagnosed on ultrasound criteria, safe alcohol consumption and absence of hepatitis B/C markers. Non- NAFLD controls did not have any ultrasound criteria for NAFLD. An updated case-control genetic association study for 10 selected genetic variants and NAFLD was also performed. Results Out of 2985 of the original cohort, 2148 (72.0%) attended follow-up (1238 [57.6%] women; mean-age 59.2 [ SD-7.6] years) in 2014, when 1320 (61.5%) were deemed NAFLD subjects. Out of 778 who initially did not have NAFLD and were not heavy drinkers throughout follow-up, 338 (43.4%) (221 [65.4%] women, mean-age 57.8 [ SD-8.0] years) had developed NAFLD after 7-years (annual incidence-6.2%). Central obesity ( OR=3.82 [95%- CI 2.09-6.99]), waist increase >5% ( OR=2.46 [95%- CI 1.20-5.05]) overweight ( OR=3.26 [95%- CI 1.90-5.60]), weight gain 5%-10% ( OR=5.70 [95%- CI 2.61-12.47]), weight gain >10% ( OR=16.94 [95%- CI 6.88-41.73]), raised plasma triglycerides ( OR=1.96 [95%- CI 1.16-3.29]) and diabetes ( OR=2.14 [95%- CI 1.13-4.06]), independently predicted the development of incident NAFLD in multivariate analysis. The updated genetic association study (1362-cases, 392-controls) showed replicated association ( P=.045, 1-tailed) with NAFLD at a candidate locus: PNPLA3 (rs738409). Conclusions In this community cohort study, the annual incidence of NAFLD was 6.2%. Incident NAFLD was associated with general and central obesity, raised triglycerides and diabetes, and showed a tendency of association with PNPLA3 gene polymorphisms. [ABSTRACT FROM AUTHOR]