Outcomes of NAFLD and MAFLD: Results from a community-based, prospective cohort study

Background

The term “metabolic (dysfunction)-associated fatty liver disease” (MAFLD) is suggested alternative for “non-alcoholic fatty liver disease” (NAFLD), as it better reflects metabolic dysfunction. No study has compared outcomes of the two diagnostic criteria.

Methods

In an ongoing, community-based, cohort-study in suburban Sri Lanka, participants were randomly selected in 2007. They were reassessed in 2014 to evaluate new-onset metabolic traits (MTs) and cardiovascular-events (CVEs). Baseline characteristics, MTs and CVEs after 7-years were compared in NAFLD and MAFLD and vs. controls. Similarly, we compared these parameters in those excluded by the NAFLD definition but captured by the MAFLD definition and vice versa, and vs. controls.

Findings

Of 2985 recruited in 2007, 940 (31.5%) had NAFLD, 990 (33.1%) had MAFLD and 362 (12.1%) were controls. When compared to NAFLD, MAFLD captured an additional 2.9% and lost 1.3% individuals. At baseline, anthropometric and metabolic traits were similar in NAFLD and MAFLD. At follow-up in 7-years, the risk of having new-onset MTs and fatal/non-fatal CVEs were similar in the groups, but were significantly higher compared to controls. Those excluded by the NAFLD definition but captured by the MAFLD definition showed higher baseline MTs compared to those excluded by the MAFLD definition but captured by the NAFLD definition, and had substantially higher risk for having new-onset MTs and CVEs compared to controls.

Interpretation

Although NAFLD and MAFLD had similar MTs at baseline, and similar outcomes after 7-years, those who were excluded by the NAFLD definition but captured by the MAFLD definition seem at higher risk of adverse outcomes than those excluded by the MAFLD definition but captured by the NAFLD definition. Although the increase in the index population was small, redefining NAFLD as MAFLD seemed to improve clinical utility.

The clinical utility of accurate NAFLD ultrasound grading: Results from a community-based, prospective cohort study

OBJECTIVES

Despite its widespread use there is no consensus on ultrasound criteria to diagnose fatty liver.

METHOD

In an ongoing, cohort-study, participants were initially screened in 2007 and reassessed in 2014 by interview, anthropometric measurements, liver ultrasonography, and blood tests. We evaluated utility of increased hepatic echogenicity alone (intermediate) compared to using additional criteria which included signal attenuation and/or vascular blunting along with increase of hepatic echogenicity (moderate-severe), to diagnose fatty liver in NAFLD. We made a comparison of the two radiologically defined groups, in order to choose a classification method for NAFLD, which may better predict baseline adverse metabolic traits (MT), and adverse metabolic and cardiovascular events (CVE) after 7-year of follow-up.

RESULTS

Of 2985 recruited in 2007, 940 (31.5 %) had moderate-severe NAFLD, 595 (19.9 %) intermediate NAFLD, and 957 (32.1 %) were controls (no fatty liver). 2148 (71.9 %) attended follow-up in 2014; they included 708 who had moderate-severe NAFLD, 446 intermediate NAFLD and 674 controls, at baseline (in 2007). At baseline, adverse anthropometric indices and MTs were significantly higher in both moderate-severe NAFLD and intermediate NAFLD compared to controls, except for low HDL. They were commoner in moderate-severe NAFLD than in intermediate NAFLD. After seven years, the odds of developing new-onset metabolic traits and CVEs were significantly higher compared to controls only in moderate-severe NAFLD.

CONCLUSIONS

Only moderate-severe NAFLD predicted risk of incident adverse MTs and CVEs. However, both moderate-severe and intermediate NAFLD were associated with higher prevalence of adverse anthropometric and metabolic traits, thereby identifying individuals who need medical intervention even among those with milder degrees of fatty liver. We therefore recommend using increased hepatic echogenicity, and not only the more stringent criteria (which include signal attenuation and/or vascular blunting), for the diagnosis of fatty liver in individuals with NAFLD.

Non-resolution of non-alcoholic fatty liver disease (NAFLD) among urban, adult Sri Lankans in the general population: A prospective, cohort follow-up study

Background

There are few studies investigating the natural course of non-alcoholic fatty liver disease (NAFLD) in the community. We assessed resolution of NAFLD in a general population cohort of urban Sri Lankans adults.

Methods

Participants were selected by age-stratified random sampling from electoral lists. They were initially screened in 2007 and re-evaluated in 2014. On both occasions structured interview, anthropometric-measurements, liver ultrasonography, and biochemical/serological tests were performed. NAFLD was diagnosed on ultrasound criteria for fatty liver, safe-alcohol consumption (<14-units/week for men, <7-units/week for women) and absence of hepatitis B/C markers. Non-NAFLD was diagnosed on absence of any ultrasound criteria for fatty liver and safe-alcohol consumption. Resolution of NAFLD was defined as absence of ultrasound criteria for fatty liver. Changes in anthropometric indices [Weight, Body-Mass-Index (BMI), waist-circumference (WC), waist-hip ratio (WHR)], clinical [systolic blood pressure (SBP), diastolic blood pressure (DBP)] and biochemical measurements [Triglycerides (TG), High Density Lipoprotein (HDL), Total Cholesterol (TC), HbA1c%] at baseline and follow-up were compared.

Results

Of the 2985 original study participants, 2148 (71.9%) attended follow-up after 7 years. This included 705 who had NAFLD in 2007 and 834 who did not have NAFLD in 2007. Out of 705 who had NAFLD in 2007, 11(1.6%) changed their NAFLD status due to excess alcohol consumption. After controlling for baseline values, NAFLD patients showed significant reduction in BMI, weight, WHR, HDL and TC levels and increase in HbA1c levels compared to non-NAFLD people. Despite this, none of them had complete resolution of NAFLD.

Conclusion

We did not find resolution of NAFLD in this general population cohort. The observed improvements in anthropometric, clinical and biochemical measurements were inadequate for resolution of NAFLD.

Lean non-alcoholic fatty liver disease (lean NAFLD): characteristics, metabolic outcomes and risk factors from a 7-year prospective, community cohort study from Sri Lanka

INTRODUCTION

While patients with non-alcoholic fatty liver disease (NAFLD) are mostly overweight or obese, some are lean.

METHODS

In a community-based follow-up study (baseline and follow-up surveys performed in 2007 and 2014), we investigated and compared the clinical characteristics, body composition, metabolic associations and outcomes, and other risk factors among individuals with lean (BMI < 23 kg/m²) NAFLD, non-lean (BMI ≥ 23 kg/m²) NAFLD and those without NAFLD. To investigate associations of selected genetic variants, we performed a case-control study between lean NAFLD cases and lean non-NAFLD controls.

RESULTS

Of the 2985 participants in 2007, 120 (4.0%) had lean NAFLD and 816 (27.3%) had non-lean NAFLD. 1206 (40.4%) had no evidence of NAFLD (non-NAFLD). Compared to non-lean NAFLD, lean NAFLD was commoner among males (p < 0.001), and had a lower prevalence of hypertension (p < 0.001) and central obesity (WC < 90 cm for males, < 80 cm for females) (p < 0.001) without prominent differences in the prevalence of other metabolic comorbidities at baseline survey. Of 2142 individuals deemed as either NAFLD or non-NAFLD in 2007, 704 NAFLD individuals [84 lean NAFLD, 620 non-lean NAFLD] and 834 individuals with non-NAFLD in 2007 presented for follow-up in 2014. There was no difference in the occurrence of incident metabolic comorbidities between lean NAFLD and non-lean NAFLD. Of 294 individuals who were non-NAFLD in 2007 and lean in both 2007 and 2014, 84 (28.6%) had developed lean NAFLD, giving an annual incidence of 4.1%. Logistic regression identified the presence of diabetes at baseline, increase in weight from baseline to follow-up and a higher educational level as independent risk factors for the development of incident lean NAFLD. NAFLD association of PNPLA3 rs738409 was more pronounced among lean individuals (one-tailed p < 0.05) compared to the whole cohort sample.

CONCLUSION

Although lean NAFLD constitutes a small proportion of NAFLD, the risk of developing incident metabolic comorbidities is similar to that of non-lean NAFLD. A PNPLA3 variant showed association with lean NAFLD in the studied population. Therefore, lean NAFLD also warrants careful evaluation and follow-up.

Clinical, biochemical and histological characteristics of a Sri Lankan population of non-alcoholic steatohepatitis (NASH) patients

BACKGROUND

Non-alcoholic steatohepatitis (NASH) is common and can progress to cirrhosis. It has been regarded as a 'disease of affluence' and there are only a few reports from developing countries.

OBJECTIVE

To describe the clinical, biochemical, and histological characteristics of a cohort of NASH patients in Sri Lanka, and to determine their short term outcome following modifications of lifestyle.

METHOD

Patients who had a liver biopsy for investigation of raised hepatic enzymes were assessed during the period May 1999 - May 2003. Patients who had an alcohol intake of over 40 g/week were excluded. Detailed clinical and biochemical data of patients with histologically confirmed NASH were compiled. Histological grading and staging was done using the Brunt system. The patients were advised on lifestyle modifications and the control of diseases known to be associated with NASH. They were followed up at 3 -monthly intervals.

RESULTS

During the study period liver biopsies were performed on 296 patients and 100 ( 35.1%) were diagnosed as having NASH. (Men = 79, Mean age 37.2 years, SD 10.6). Risk factors for NASH included diabetes mellitus (55%), obesity (52%), hyperlipidaemia (54%), a family history of risk factors (66%) and a high dietary fat intake (66%). However, 44.3% of men and 33.3% of women were not overweight. The histological grading and staging of 80 biopsies showed Grade 1 in 31 (38.8%), Grade 2 in 29 (36.3%), Grade 3 in 20 (25%), Stage 1 in 57 (71.3%) Stage 2 in 13 (16.3%), Stage 3 in 2 (2.5%) and Stage 4 in 8 (10%). In 55/91 (60.4%) patients who were followed up for a median of 2.5 years (range 1-4 years) the serum transaminases returned to normal in a median of 7 months (range 3-14 months).

CONCLUSION

The clinical, biochemical and histological features of NASH patients in our series are similar to that reported in western countries. However "lean males" accounted for a significant proportion. In the short term a majority of patients showed improvement in serum transaminases with lifestyle modification.