Non-alcoholic liver disease (NAFLD)

Primary non-alcoholic liver disease (NAFLD) refers to the accumulation of excess fat (triglycerides) in the liver, where triglycerides are present in more than 5% of liver cells (hepatocytes) (National Institute for Health and Clinical Excellence [NICE], 2023), and the cause is unrelated to alcohol consumption or any other reasons. The disease is the most common cause of chronic liver disease worldwide, affecting 24% of the population, and has a huge impact on global public health care with a considerable financial burden (Thanapirom and Tsochatzis, 2019). Up to 90% of patients with NAFLD have simple steatosis, which carries a relatively benign prognosis, with no overall increase in mortality (Dyson et al, 2013). However, approximately 10–30% have the potentially progressive form of NAFLD, non-alcoholic steatohepatitis (NASH), which is associated with hepatocellular injury and inflammation (Dyson et al, 2013). Approximately 25–40% of patients with NASH will develop progressive liver fibrosis, ultimately resulting in

The underlying processes leading to NAFLD are highly complex and involve an interaction between several factors. The condition is now considered to be a manifestation of metabolic syndrome (central adiposity, dyslipidaemia, hyperglycemia, hypertension, and hyperuricaemia), in combination with insulin resistance (Peng et al, 2022). Metabolic risk factors for NAFLD associated with features of the metabolic syndrome include:

• Central obesity: Central obesity is a major risk factor in NAFLD, which is strongly associated with obesity and increased waist circumference, particularly in people with a BMI greater than 30 kg/m² and increased waist circumference (≥94 cm in men and ≥80 cm in women in White populations) (NICE, 2023).
• Impaired glucose metabolism or type 2 diabetes: Prevalence of NAFLD among those with confirmed type 2 diabetes is approximately 55% (NICE, 2023).
• Dyslipidaemia: Fatty liver is significantly associated with a higher prevalence of hypertriglyceridaemia and low high-density lipoprotein (HDL) (Huh et al, 2022).
• Hypertension

The identification of pre-symptomatic patients at risk of NAFLD/NASH is regarded as the best way to enable earlier disease intervention. Most patients with NAFLD/NASH are asymptomatic and usually have nonspecific symptoms. However, rarely, some patients may present with symptoms of fatigue, anorexia, nausea, vomiting, malaise, headache, and vague right upper quadrant abdominal discomfort (Savari and Mard, 2024).

There is no specific test to confirm the diagnosis. Often the condition is detected following investigations for another reason. When taking the history during a consultation, concerns relating to causative factors found on assessment may raise suspicion of NAFLD, and in this case, investigations in primary care include (NICE, 2023):

• Bloods including LFTs: Elevated alanine aminotransferase (ALT) levels may be raised up to 3 times the upper limit of normal and result is greater than levels of aspartate aminotransferase (AST) levels. (Please note that normal ALT levels do not exclude NAFLD)
• Abdominal ultrasound scan may show fatty liver changes. (Please note that a normal scan does not exclude NAFLD)
• Bloods to exclude other causes (Immunoglobulin levels, ferritin and transferrin saturation and viral hepatitis) are negative.

Bloods and ultrasound scan results can be normal and should not be used to rule out NAFLD (Byrne et al, 2018).

Referral to secondary care

There is no specific drug treatment available for NAFLD, and management therefore aims to reduce the risk of disease progression and prevent complications. Diet, weight loss and physical activity are central to the treatment of NAFLD, and patients are advised to incorporate changes to their lifestyle, such as (Romero Gomez et al, 2017; Huh et al, 2022):

• The Mediterranean diet: Overweight and obese patients should be advised to aim to reduce their average daily calorie intake by at least 500–1000 kcal. The Mediterranean diet includes high levels of omega-3-fatty acids and antioxidants and has been found to reduce hepatic fat accumulation.
• Weight loss:  Sustained weight loss of about 5% of initial body weight can reduce steatosis, liver enzymes and can also result in clinically meaningful reductions in triglycerides, blood glucose, haemoglobin A1c, and the risk of developing type 2 diabetes. Larger reductions in weight of 7 to 10% are associated

Byrne CD, Patel J, Scorletti E, Targher G. Tests for diagnosing and monitoring non-alcoholic fatty liver disease in adults. BMJ. 2018 Jul 12;362:k2734. doi: 10.1136/bmj.k2734.

Chaudhry A, Noor J, Batool S, Fatima G, Noor R. Advancements in Diagnostic and Therapeutic Interventions of Non-alcoholic Fatty Liver Disease: A Literature Review. Cureus. 2023 Sep 8;15(9):e44924. doi: 10.7759/cureus.44924.

Dyson JK, Anstee QM, McPherson S. Non-alcoholic fatty liver disease: a practical approach to diagnosis and staging. Frontline Gastroenterol. 2014 Jul;5(3):211-218. doi: 10.1136/flgastro-2013-100403.

Huh Y, Cho YJ, Nam GE. Recent Epidemiology and Risk Factors of Nonalcoholic Fatty Liver Disease. J Obes Metab Syndr. 2022 Mar 30;31(1):17-27. doi: 10.7570/jomes22021.

Mantovani A, Dalbeni A. Treatments for NAFLD: State of Art. Int J Mol Sci. 2021 Feb 26;22(5):2350. doi: 10.3390/ijms22052350. 

Michalowski J, Zajac S. NAFLD fibrosis score calculator. 2024. Available at: https://www.omnicalculator.com/health/nafld-fibrosis-score

National Institute for Health and Care Excellence. Non-alcoholic fatty liver disease. 2023. Available at: https://cks.nice.org.uk/topics/non-alcoholic-fatty-liver-disease-nafld/

Paternostro R, Trauner M. Current treatment of non-alcoholic fatty liver disease. J Intern Med. 2022 Aug;292(2):190-204. doi:

Part 1: Procedures for assessing people’s needs for person-centred care

2.1: Understand and apply the aims and principles of health promotion, protection and improvement and the prevention of ill health when engaging with people 

2.5: Promote and improve mental, physical, behavioural, and other health-related outcomes by understanding and explaining the principles, practice, and evidence base for health screening programmes 

Part 2: Procedures for the planning, provision and management of person-centred nursing care

3.11: Undertake routine investigations, interpreting and sharing findings as appropriate

3.12: Interpret results from routine investigations, taking prompt action when required by implementing appropriate interventions, requesting additional investigations, or escalating to others 

4.2: Work in partnership with people to encourage shared decision making to support individuals, their families, and carers to manage their own care when appropriate

4.3: Demonstrate the knowledge, communication and relationship management skills required to provide people, families and carers with accurate information that meets