The Olmsted NAFLD Epidemiology Study (TONES)


About this study

About this study

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the world and a major public health issue in the US. It is estimated to affect 1 in 4 adults and it is most commonly found in people who are overweight or obese. Because it is a silent disease (without symptoms until end stage) and the lab tests can be normal, it can be missed in early stages. The fat in the liver can lead to inflammation and eventually scar deposition, which can progress to cirrhosis, liver cancer and need for liver transplantation.

This study aims to assess how common this disease is in Olmsted County, what markers can identify the disease early to prevent progression to cirrhosis and what other medical problems occur in people with NAFLD in addition to the liver complications. We plan to enroll a large number of adults, assess their liver with state-of-the-art tests available at Mayo Clinic and follow them over several years to monitor for disease progression and other health complications. The ultimate goal of the study is to identify new markers that predict presence of fatty liver and poor health outcomes, in order to improve population health in the community.

Participation eligibility

Participants will be identified from the Olmsted County population age 18 or older.

Inclusion criteria:

1.         Adults age 18 years or older

2.         Olmsted County residents at the time of study entry


Exclusion criteria:

1.         Pediatric population (age<18)

2.         Unwilling to participate or unable to consent

3.         Known liver disease other than NAFLD at the time of survey

4.         Pregnant women

5.         Alcohol use in excess (14 drinks or more per week for women and 21 drinks or more per week for men)

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

  • Adults age 18 years or older.
  • Olmsted County residents at the time of survey.

Exclusion Criteria:

  • Pediatric population (age < 18 years old).
  • Unwilling to participate or unable to consent.
  • Known liver disease other than NAFLD at the time of survey.
  • Pregnant women.

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Alina Allen, M.D.

Open for enrollment

Contact information:

Suzanne Greiner

(507) 293-0913

More information


Publications are currently not available

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