NON-ALCOHOLIC FATTY LIVER DISEASE AND RELATIONSHIP WITH ADIPOSITY IN NIGERIAN PATIENTS WITH TYPE 2 DIABETES MELLITUS: THE IBADAN EXPERIENCE

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C.O. Aransiola¹, W.O. Balogun²

1. Department of Medicine, University College Hospital, Ibadan, Nigeria.
2. Department of Medicine, College of Medicine, University of Ibadan and University College Hospital, Ibadan, Nigeria

Abstract

Background: Non-Alcoholic Fatty Liver Disease (NAFLD) is the commonest cause of chronic liver disease and is frequently found in patients with Type 2 diabetes (T2D). NAFLD is associated with excess adiposity and prevalence could vary by BMI sub-groups. There remain conflicting reports about the prevalence of NAFLD in T2D in Africa, particularly Nigeria. We studied the prevalence of NAFLD and its relationship to adiposity in a cohort of persons living with T2D.

Methodology: A cross-sectional study of 147 consecutive T2D patients, attending the Diabetes Clinic, at the University College Hospital, Ibadan, was conducted over a period of two months. Clinical history and anthropometric indices were obtained; in addition, blood samples were taken and analyzed for FBS, HbA1c, Fasting Lipids Profile, HBsAg, Anti HCV, ALT, AST, ALP, GGT and albumin. Hepatic ultrasound was conducted by an experienced sonologist. Data were collected with the aid of a pre-tested semi-quantitative questionnaire and were analysed using the SPSS software 15.0 version.

Results: Prevalence of NAFLD in persons living with T2D in 139 participants with complete data was 46% with a mean (SD) BMI of 27.4 (5.6). The participants with NAFLD had significantly excess adiposity, particularly the obese subgroup compared to those without [32 (50.0%) and 5 (6.7%), p = 0.001], respectively. Factors associated with NAFLD include female sex, older age, increased BMI, increased waist circumference, raised serum triglycerides, higher HbA1c levels, and raised alkaline phosphate levels. Sex, BMI, waist circumference and serum ALP were independently associated with NAFLD. Of notable interest is the raised serum ALP levels in subjects with NAFLD compared to those without NAFLD: mean (SD) = 30.6 (16.5) and 23.7 (15.3), respectively (p = 0.020).

Conclusion: NAFLD is relatively common in patients living with type 2 diabetes and is associated with excess adiposity and increased alkaline phosphatase. Dietary and lifestyle changes can play a pivotal role in reducing prevalence of these diseases. Further, ALP could be a useful marker to assess the progression of NAFLD.

Introduction

The world is witnessing increasing burden of NonAlcoholic Liver Disease (NAFLD) just as diabetes mellitus. The global prevalence of NAFLD or MAFLD (Metabolic-Associated Fatty Liver Disease) as described by some is 32.4%¹, while that of diabetes is 10.5%.² Notably, both conditions are associated, and the linkage is bidirectional.³ The progression of NAFLD through NASH (Non-Alcoholic Steatohepatitis) and liver cirrhosis eventually results in hepatocellular cancer, the second commonest cause of short lifespan in cancer patients.⁴ Similarly, diabetes is a leading cause of cardiovascular death, end-stage kidney failure, blindness and non-traumatic amputation.⁵ The co-existence of both conditions expectedly leads to increased mortality.⁶ A common risk factor for both NAFLD and type 2 diabetes (T2D) is obesity and its associated insulin resistance. However, NAFLD is sometimes found in lean individuals.⁷

Globally, the burden of NAFLD in diabetic patients varies between 30-80%, depending on factors including means of diagnosis of NAFLD, age, gender, BMI and diabetes duration.⁸ Similarly, in sub-Saharan Africa, the prevalence rates of NAFLD in diabetic patients range widely between 50.3-73.0%

Although there are fewer studies in Nigerian T2D, the available studies from the South-western region showed similar wide variation. However, interestingly, out of the three prevalence rates from the same region in Nigeria, two support very low rates – 8.7% and 16.7%,^9,10 while the remaining one reported a high prevalence rate of 68.8%.¹¹ Nevertheless, questions have been raised whether the low prevalence rates are true reflection of NAFLD burden in African diabetic patients.¹² Therefore, the true prevalence of NAFLD in Nigerian T2D patients, particularly from the South-western region remain unresolved. It is important to know the true burden of NAFLD in diabetic patients, so healthcare practitioners could appreciate the enormity and the requisite approach to care and interventions could be instituted.

In this work, we aimed to determine the prevalence of NAFLD and its relationship with excess adiposity among T2D patients attending the Nigerian premiere teaching hospital, the University College Hospital, Ibadan.