Frequency and Determinants of Non-Alcoholic Fatty Liver Disease Among Adults With Type 2 Diabetes Mellitus: A Cross-Sectional Study Protocol

Assessing the burden of ultrasound-defined fatty liver disease and its metabolic, clinical, and lifestyle-related determinants in adults with type 2 diabetes.

SPECIALTY  Medicine     CATEGORY  Research Methods

Abstract

Background: Non-alcoholic fatty liver disease (NAFLD) frequently coexists with metabolic conditions, including type 2 diabetes mellitus (T2DM). Identifying its local burden and associated factors may support earlier recognition and targeted clinical assessment.

Objective: To determine the frequency and determinants of NAFLD among adults with T2DM.

Methods: This protocol describes a cross-sectional study with a planned sample of 191 adults aged 30–65 years who have had T2DM for at least two years. Participants will be recruited using non-probability consecutive sampling. Data will include demographic and clinical characteristics, anthropometric measurements, lifestyle factors, fasting lipid profile, HbA1c, liver enzymes, and abdominal ultrasonography. NAFLD will be identified using the protocol’s ultrasound-based operational definition in the absence of significant alcohol intake.

Analysis: Quantitative variables will be summarized using means and standard deviations or appropriate distribution-based summaries. Categorical variables will be reported as frequencies and percentages. Binary logistic regression will be used to assess factors associated with NAFLD, with odds ratios and 95% confidence intervals reported.

Protocol status: This article describes the planned study. No participant results or study findings are reported.

Keywords

Non-alcoholic fatty liver disease; type 2 diabetes mellitus; fatty liver; metabolic risk factors; abdominal ultrasonography; cross-sectional study.

Introduction

Non-alcoholic fatty liver disease (NAFLD) is characterized by excess fat accumulation in the liver in the absence of significant alcohol consumption. Its clinical spectrum can include simple steatosis, steatohepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. NAFLD is closely linked to insulin resistance and metabolic abnormalities, including obesity, dyslipidemia, and type 2 diabetes mellitus.

People living with T2DM represent an important group for assessment because metabolic dysfunction can coexist with fatty liver disease and may complicate long-term health management. The synopsis cites prior studies reporting a notable frequency of NAFLD among diabetic populations, including a report of 58% among patients with T2DM in Pakistan [9].

Evidence from Southern Punjab is described in the source synopsis as limited. Estimating the frequency of NAFLD and examining associated demographic, metabolic, and lifestyle factors may help characterize the local burden and inform discussions about early assessment and risk-factor management. Abdominal ultrasonography is the planned method for identifying NAFLD in this study protocol.

Objective

To determine the frequency and determinants of non-alcoholic fatty liver disease among adults with type 2 diabetes mellitus.

Operational Definitions

Non-alcoholic fatty liver disease (NAFLD): NAFLD will be considered present when at least two of the following three ultrasound features are present in the absence of significant alcohol intake, assessed by history: (1) a bright liver, defined as increased liver echotexture compared with the kidney; (2) blurring of vessels and narrowing of hepatic veins; and (3) deep attenuation of the ultrasound signal.

Hypertension: A known diagnosis identified through medical records and antihypertensive treatment history, as specified in the source protocol.

Smoking: Current smoking defined in the source protocol as smoking at least 10 cigarettes per day for two years.

Obesity: Body mass index (BMI) of at least 30 kg/m². BMI will be calculated as weight in kilograms divided by height in meters squared.

Dyslipidemia: The presence of one or more lipid abnormalities listed in the source protocol: total cholesterol at least 240 mg/dL, high-density lipoprotein (HDL) below 40 mg/dL, low-density lipoprotein (LDL) at least 130 mg/dL, or triglycerides at least 150 mg/dL.

Diabetes control: HbA1c will be categorized using the bands listed in the source synopsis: excellent (6.5–7.5%), good (7.5–8.5%), fair (8.5–9.5%), and poor (>9.5%). The overlapping boundary values should be clarified in the approved protocol before final analysis.

Socioeconomic status: Monthly household income categories will follow the brackets listed in the source synopsis: low (up to PKR 11,605), lower-middle (PKR 11,606–45,395), upper-middle (PKR 45,396–140,461), and high (above PKR 140,461).

Materials and Methods

Study Design and Duration

A cross-sectional study is planned over six months after study approval.

Study Setting

The study is planned in a clinical medicine setting in Southern Punjab, Pakistan. The institution and individual researcher details are intentionally omitted from this website version.

Sample Size and Sampling Technique

The planned sample size is 191 participants, calculated using a WHO sample-size calculator based on a single-proportion formula, an assumed NAFLD frequency of 58% among patients with T2DM, and a 95% confidence level. Non-probability consecutive sampling will be used.

Eligibility Criteria

Inclusion criteria: adults aged 30–65 years, of any sex, with a documented diagnosis of T2DM for at least two years.

Exclusion criteria: current use of lipid-lowering medication; significant alcohol intake (>40 g/week as specified in the synopsis); known chronic liver disease; use of potentially hepatotoxic medicines listed in the synopsis (including corticosteroids, amiodarone, methotrexate, tamoxifen, and valproate); congestive heart failure; chronic kidney disease; malignancy; pregnancy or lactation; and acute infection at enrolment.

Data Collection Procedure

After obtaining approval from the relevant ethics review committee and required research authority, eligible participants will be enrolled after written informed consent. Demographic and clinical data will include age, sex, urban or rural residence, socioeconomic status, duration of T2DM, antidiabetic treatment, hypertension, smoking, physical activity, and family history of liver disease or NAFLD.

Anthropometric measurements will include height, weight, waist circumference, and hip circumference. BMI and waist-to-hip ratio will be calculated. Following a 12-hour fast, blood samples will be collected for total cholesterol, LDL, HDL, triglycerides, HbA1c, and liver function tests including ALT, AST, and alkaline phosphatase. Abdominal ultrasonography will be performed to assess NAFLD according to the operational definition. Information will be recorded on a structured study proforma.

Data Analysis Plan

Data will be analyzed using IBM SPSS version 27.0. The Shapiro–Wilk test will be used to assess the normality of quantitative variables. Quantitative data—including age, anthropometric measurements, liver enzymes, diabetes duration, HbA1c, and lipid levels—will be summarized using means and standard deviations as specified in the synopsis. Categorical variables, including NAFLD status, sex, residence, socioeconomic status, obesity, hypertension, dyslipidemia, smoking, physical activity, family history, antidiabetic treatment, and diabetes-control category, will be summarized as frequencies and percentages.

Binary logistic regression will be used to assess determinants of NAFLD, with NAFLD status (yes/no) as the outcome variable. Independent variables will first be evaluated in univariable analyses; crude odds ratios with 95% confidence intervals will be reported. Variables meeting the protocol’s screening threshold (p ≤ 0.20) will be considered for the forward stepwise multivariable model. Adjusted odds ratios with 95% confidence intervals will be reported, and p < 0.05 will be considered statistically significant.

Outcomes and Utilization

Primary outcome: the frequency of ultrasound-defined NAFLD among adults with T2DM.

Secondary outcomes: assessment of potential determinants, including age, sex, duration of diabetes, obesity and waist-to-hip ratio, hypertension, dyslipidemia, glycemic control, smoking, physical activity, family history of liver disease or NAFLD, socioeconomic status, and type of antidiabetic treatment.

The proposed study is intended to provide local evidence about NAFLD among people with T2DM in Southern Punjab, where the source synopsis describes limited data. The findings may help identify modifiable risk factors, inform discussion of earlier assessment in higher-risk patients, and support clinical education around glycemic control, weight management, physical activity, and lipid management. These are intended uses; the study’s actual findings are not yet available in this protocol.

Study Schedule

The source synopsis proposes a six-month schedule: Month 1 for administrative preparation, ethics/research approvals, and team orientation; Months 1–4 for recruitment and baseline assessment; Months 2–5 for laboratory investigations, abdominal ultrasound, and data entry/verification; Month 5 for statistical analysis; Months 5–6 for thesis writing and results compilation; and Month 6 for final review and submission preparation.

Conclusion

This cross-sectional study protocol is designed to estimate the frequency of NAFLD and examine its clinical, metabolic, and lifestyle-related determinants among adults with T2DM. By using abdominal ultrasonography alongside clinical, anthropometric, and laboratory data, the study aims to generate locally relevant evidence. Conclusions about prevalence, associations, or predictive factors should be made only after data collection and analysis are completed.

References

1. Pourteymour S, Drevon CA, Dalen KT, Norheim FA. Mechanisms behind NAFLD: a system genetics perspective. Current Atherosclerosis Reports. 2023;25(11):869–878. doi:10.1007/s11883-023-01158-3.

2. Radu F, Potcovaru CG, Salmen T, Filip PV, Pop C, Fierbințeanu-Braticievici C. The link between NAFLD and metabolic syndrome. Diagnostics. 2023;13(4):614. doi:10.3390/diagnostics13040614.

3. Yip TC, Lee HW, Chan WK, Wong GL, Wong VW. Asian perspective on NAFLD-associated HCC. Journal of Hepatology. 2022;76(3):726–734. doi:10.1016/j.jhep.2021.09.024.

4. Huh Y, Cho YJ, Nam GE. Recent epidemiology and risk factors of nonalcoholic fatty liver disease. Journal of Obesity and Metabolic Syndrome. 2022;31(1):17–27. doi:10.7570/jomes22021.

5. Shah AS, Khan S, Rahim H, Chishti KA, Ghafoor Khan AG. Prevalence of non-alcoholic fatty liver and non-alcoholic steatohepatitis in Peshawar Cantonment, Khyber Pakhtunkhwa, Pakistan. Pakistan Journal of Pharmaceutical Sciences. 2018;31(1):193–198.

6. Ziamanesh F, Mohammadi M, Ebrahimpour S, Tabatabaei-Malazy O, Mosallanejad A, Larijani B. Unraveling the link between insulin resistance and non-alcoholic fatty liver disease (or metabolic dysfunction-associated steatotic liver disease): a narrative review. Journal of Diabetes & Metabolic Disorders. 2023;22(2):1083–1094. doi:10.1007/s40200-023-01293-3.

7. Filozof CM, Lackner C, Romero-Gómez M, Imperial JC, McGee R, Dimick-Santos L, et al. Best practices in liver biopsy histologic assessment for nonalcoholic steatohepatitis clinical trials: expert opinion. GastroHep. 2022;2022(1):3538103. doi:10.1155/2022/3538103.

8. Baduku TS, Ibinaiye PO, Igashi JB, Usman BO, Manko M, Ahmad AE, et al. B-mode ultrasound grading of nonalcoholic fatty liver disease and association with intima-media thickness: a case-control study. Journal of the Nigerian Academy of Medicine. 2024;3(1):1–7. doi:10.4103/jnam.jnam_4_23.

9. Afzal MY, Anjum HS, Siddiqui UN. Nonalcoholic fatty liver disease (NAFLD) frequency in diabetes mellitus (DM) type-II patients. FUUAST Journal of Biology. 2016;6(1):7–10. doi:10.64793/fuuastjb.v6i1.83.