Economic Burden
With such a heavy clinical burden and a projected increase in volume over the next decade, NAFLD is expected to have a similarly exponential impact on the economic burden. A review of 976 Medicare beneficiaries with NAFLD who were hospitalized from January 1, 2010 to December 31, 2010, noted a median annual total payment of about $11,000, with significantly lower payment for patients without cirrhosis compared with those with cirrhosis ($10,146 vs $18,804, P < .01).19 Another review of 29,528 Medicare beneficiaries with NAFLD who sought outpatient care between 2005 and 2010 saw a rise in mean yearly charges in 2005 of $2,624 ± 3,308 to $3,608 ± 5,132 in 2010 (P < .05).20
To place these costs in perspective, Allen and colleagues reviewed a large national claims database of individuals enrolled with private and Medicare advantage health plans.21 Comparing patients with NAFLD with a control matched group with similar metabolic comorbidities the study revealed annual median outpatient care costs of $5,363 for the patients with NAFLD with Medicare advantage plans, which was significantly higher than $4,111 for the control group. Projection models based on similar Medicare beneficiaries estimate a rise in annual US economic burden to $103 billion from direct medical care costs alone and another $188 billion in societal costs related to NAFLD.22 New NASH/antifibrotic therapies are being evaluated in clinical trials and are expected to lead to even higher costs. Given the similarities in the trends of NAFLD prevalence between veterans and the general population, it is anticipated that a similar growth and burden in health care utilization cost will affect the VHA.
Association With Other Chronic Medical Conditions
NAFLD is closely associated with metabolic syndrome (Figure 3). Concurrent diagnosis of NAFLD in patients with existing T2DM is associated with poor glycemic control, progressive diabetic retinopathy, diabetic nephropathy, increased risk of cardiovascular complications, and a 2-fold increase in all-cause mortality.1-3
Additionally, a significant number of asymptomatic individuals with T2DM have undiagnosed advanced NAFLD fibrosis.23 NAFLD also is independently associated with new onset T2DM. In a 14-year follow-up study of biopsy-proven patients with NAFLD, 58% developed T2DM and another 20% developed impaired glucose tolerance.24 Similarly, NAFLD is independently associated with coronary artery disease (CAD) after adjusting for known cardiovascular disease risk factors; furthermore, CAD is the leading cause of mortality among NAFLD patients.1,25-27 Large population-based studies also have reported that obstructive sleep apnea is independently associated with NAFLD and is an independent risk factor for significant hepatic fibrosis among those with NAFLD.28-30Similar associations have been described between NAFLD and other metabolic conditions such as obesity, hypertension, hypothyroidism, polycystic ovarian syndrome, and chronic kidney disease.31 Identifying patients with NAFLD may help with screening for the above metabolic diseases because patients with NAFLD (by comparison with patients with non-NAFLD) are at higher risk for diabetic, cardiovascular, and pulmonary complications and may warrant a more intensive treatment approach.
Conclusion
A leading cause of chronic liver disease and cirrhosis in the US, NAFLD is independently associated with metabolic syndrome and all-cause mortality. The number of veterans with NAFLD is expected to grow significantly over the coming years given the ongoing epidemic of adult and childhood obesity and T2DM. It is associated with many other medical conditions, including cardiovascular disease and complications, incident metabolic diseases, and may progress to liver cirrhosis and cirrhosis associated complications like HCC and liver failure. The current lack of any approved drug treatment for NASH/fibrosis and the shortage of organs for liver transplant emphasize the need for comprehensive primary prevention measures to reduce the future health and economic costs associated with NAFLD.