NAFLD Risk Increased Among Men and Patients With Overweight, Obesity

The incidence rate of nonalcoholic fatty liver disease is 4,613 cases per 100,000 years.

There is an increased risk of developing nonalcoholic fatty liver disease (NAFLD) among men and patients who have overweight or obesity, according to study findings in the Journal of Hepatology.

While NAFLD impacts many people worldwide, there is limited data regarding the incidence rate. Researchers conducted a systematic review and meta-analysis to estimate the incidence rate of NAFLD to help inform treatment and preventative measures.

Researchers included observational cohort studies with patients 18 years and older without NAFLD at baseline. All studies included in the analysis had data on NAFLD development during the study and follow-up data. Exclusion criteria were studies including patients with NAFLD at baseline, studies with certain comorbid conditions (HIV, HCV, HBV, etc.), or studies focusing on a specific demographic.

The primary endpoint was the incidence of NAFLD, defined as the number of people without NAFLD who developed NAFLD during the study period.

As treatment for NAFLD is based on exercise and diet along with treatment of comorbidities as indicated, prevention of NAFLD should remain a public health focus.

A total of 19,406 articles were identified on PubMed, Embase, and the Cochrane Library; and after exclusion, 69 studies with 8,798,344 patients remained. To diagnose NAFLD, 63 studies used ultrasounds, 3 used fatty liver index, 2 used diagnosis codes, and 1 used controlled attenuation parameters.

A majority of studies were conducted in mainland China and Hong Kong (27 studies), South Korea (24 studies), and Japan (14 studies). There was 1 study from each of the following countries: Sri Lanka, Israel, the United Kingdom, and the United States.

Across the 63 studies (1,201,807 patients) using ultrasound to diagnose NAFLD, the NAFLD incidence was 4612.8 per 100,000 person-years (95% CI, 3931.5-5294.2).

Among 6 studies with 7,596,537 patients diagnosed with NAFLD using methods other than ultrasound, the NAFLD incidence was 1556 (Number of patients with NAFLD, 182,316; 95% CI, 498.3-2613.7).

All subsequent analysis was conducted using the 63 studies utilizing ultrasound to diagnose NAFLD. There were no statistically significant differences in NAFLD incidence based on sample size (P =.90). While observed NAFLD incidence was higher in community centers when compared with clinical centers, there was no statistical significance (5781.5 [20 studies, 219,635 persons] vs 4064.5 [43 studies, 982,172 persons], P =.055).

There are no statistically significant differences between studies that were conducted in 2010 or beyond compared with studies conducted before 2010 (5037.2 [37 studies, 730,235 persons] vs 3988.9 [26 studies, 245 471,572 studies], P =.099).

Results show that the overall NAFLD incidence per 100,000 person-years among men was nearly twice than that of women (5943.8 vs 3671.7; P =.0013).

Patients with overweight or obesity were at a 3-fold greater risk of developing NAFLD when compared with patients with a normal weight (8416.6 vs 3358.2; P <.0001). There was also an increased risk of developing NAFLD for patients with obesity compared with nonobese patients (8669.6 vs 2963.9; P <.0001).

Study limitations include lack of generalizability, publication bias, and only including patients diagnosed by ultrasound in most of the analysis.

“As treatment for NAFLD is based on exercise and diet along with treatment of comorbidities as indicated, prevention of NAFLD should remain a public health focus,” the study authors concluded.

Disclosure: One study author declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of the author’s disclosures.

This article originally appeared on Gastroenterology Advisor


Le MH, Le DM, Baez TC, et al. Global incidence of nonalcoholic fatty liver disease: a systematic review and meta-analysis of 63 studies and 1,201,807 persons. J Hepatol. Published online April 9, 2023. doi:10.1016/j.jhep.2023.03.040.