In the Journals

Global prevalence of concurrent NAFLD in type 2 diabetes at 55%

Zobair M. Younossi, MD
Zobair M. Younossi

Results from a systematic review and meta-analysis revealed the global prevalence of fatty liver disease in patients with type 2 diabetes, ranging from approximately 55% for nonalcoholic fatty liver disease to 37% for nonalcoholic steatohepatitis, affected specifically by region and age.

“Our meta-analysis provides evidence that the prevalence of NAFLD and NASH in patients with [type 2 diabetes] is very high,” Zobair M. Younossi, MD, chairman of the department of medicine at Inova Fairfax Medical Center, Fairfax, Virginia, and colleagues wrote. “Additionally, a significant proportion of these patients have underlying advanced fibrosis and experience higher rates of adverse outcomes such as all-cause, [cardiovascular disease] or liver-specific mortality. In this context, [type 2 diabetes] not only fuels the epidemic of NAFLD but also promotes the progressiveness of adverse outcomes.”

Younossi and colleagues analyzed 80 studies from around the globe published between 2003 and 2018. From the 49,419 patients included in studies, the estimated global NAFLD presence among patients with type 2 diabetes was 55.48% (95% CI, 47.26-63.67).

By region, prevalence ranged from 51.77% in the Untied States, 56.83% in Latin America, 67.97% in Europe, 52.04% in East Asia, 57.87% in South Asia, 67.29% in West Asia, and 30.39% in Africa. Based on the 8.5% global prevalence of type 2 diabetes, the predicted prevalence of concurrent type 2 diabetes and NAFLD was 47.16 per 1,000 global population.

The researchers pointed out that while the lowest prevalence rates were reported from Africa, “these rates for the prevalence of NAFLD are almost twice the prevalence rates that had previously been reported for the general population from the same regions.”

Geographic region (P < .001) and mean age (P = .033) correlated with the prevalence of NAFLD with 63.9% heterogeneity, according to a multivariate analysis.

Younossi and colleagues also found that the global prevalence of NASH among patients with type 2 diabetes was 37.33% (95% CI, 24.7-50.02) and the global prevalence of advanced fibrosis was 4.8% (95% CI, 0-17.46).

The investigators noted that there remains a lack of well-conducted studies to assess the prevalence and progression nature of NAFLD and NASH in patients with type 2 diabetes, and that future studies much be carried out in a prospective manner with carefully defined study definitions and validated outcomes.

“Additionally, there has to be a close engagement and collaboration with experts in diabetes,” they wrote. “In fact, it will be only through these collaborations between primary care, hepatology and diabetologists that could have a better understanding of the epidemiologic and clinical burden of NAFLD and NASH in diabetic population.” – by Talitha Bennett

Disclosure: Younossi reports he received research funds or served as consultant to AbbVie, Bristol-Myers Squibb, Gilead Sciences, Intercept, NovoNordisk, Terns and Viking. Please see full report for all other authors’ relevant financial disclosures.

Zobair M. Younossi, MD
Zobair M. Younossi

Results from a systematic review and meta-analysis revealed the global prevalence of fatty liver disease in patients with type 2 diabetes, ranging from approximately 55% for nonalcoholic fatty liver disease to 37% for nonalcoholic steatohepatitis, affected specifically by region and age.

“Our meta-analysis provides evidence that the prevalence of NAFLD and NASH in patients with [type 2 diabetes] is very high,” Zobair M. Younossi, MD, chairman of the department of medicine at Inova Fairfax Medical Center, Fairfax, Virginia, and colleagues wrote. “Additionally, a significant proportion of these patients have underlying advanced fibrosis and experience higher rates of adverse outcomes such as all-cause, [cardiovascular disease] or liver-specific mortality. In this context, [type 2 diabetes] not only fuels the epidemic of NAFLD but also promotes the progressiveness of adverse outcomes.”

Younossi and colleagues analyzed 80 studies from around the globe published between 2003 and 2018. From the 49,419 patients included in studies, the estimated global NAFLD presence among patients with type 2 diabetes was 55.48% (95% CI, 47.26-63.67).

By region, prevalence ranged from 51.77% in the Untied States, 56.83% in Latin America, 67.97% in Europe, 52.04% in East Asia, 57.87% in South Asia, 67.29% in West Asia, and 30.39% in Africa. Based on the 8.5% global prevalence of type 2 diabetes, the predicted prevalence of concurrent type 2 diabetes and NAFLD was 47.16 per 1,000 global population.

The researchers pointed out that while the lowest prevalence rates were reported from Africa, “these rates for the prevalence of NAFLD are almost twice the prevalence rates that had previously been reported for the general population from the same regions.”

Geographic region (P < .001) and mean age (P = .033) correlated with the prevalence of NAFLD with 63.9% heterogeneity, according to a multivariate analysis.

Younossi and colleagues also found that the global prevalence of NASH among patients with type 2 diabetes was 37.33% (95% CI, 24.7-50.02) and the global prevalence of advanced fibrosis was 4.8% (95% CI, 0-17.46).

The investigators noted that there remains a lack of well-conducted studies to assess the prevalence and progression nature of NAFLD and NASH in patients with type 2 diabetes, and that future studies much be carried out in a prospective manner with carefully defined study definitions and validated outcomes.

“Additionally, there has to be a close engagement and collaboration with experts in diabetes,” they wrote. “In fact, it will be only through these collaborations between primary care, hepatology and diabetologists that could have a better understanding of the epidemiologic and clinical burden of NAFLD and NASH in diabetic population.” – by Talitha Bennett

Disclosure: Younossi reports he received research funds or served as consultant to AbbVie, Bristol-Myers Squibb, Gilead Sciences, Intercept, NovoNordisk, Terns and Viking. Please see full report for all other authors’ relevant financial disclosures.