Bidirectional Association between Hypertension and NAFLD: A Systematic Review and Meta-Analysis of Observational Studies

Table 1

Characteristics of 11 observational studies included in the meta-analysis.

Author and year	Country	Study characteristics	Mean follow-up duration	Fatty liver diagnosis	Hypertension diagnosis	Outcomes	Adjustments	Quality score
Ryoo et al., 2014 [12]	South Korea	Population-based; n = 22,090 men; mean age 42.1 y; 6,554 mild NAFLD; 1,007 moderate to severe NAFLD; without baseline HTN; 3,820 incident HTN	Prospective cohort; 5 years	Liver ultrasound	SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg or current use of antihypertensive agents	Association with incident HTN	Age, BMI, TG, serum creatinine, AST, ALT, GGT, recent smoking status, regular exercise, diabetes mellitus	7
Sung et al., 2014 [13]	South Korea	Population-based; n = 11,448; mean age 41 y; 7,940 men; 2,958 baseline fatty liver; without baseline HTN; 911 incident HTN	Retrospective cohort; 5 years	Liver ultrasound	SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg or current use of antihypertensive agents	Association with incident HTN	Age, sex, alcohol consumption, smoking status, exercise, SBP, BMI, diabetes status, GGT, HOMA-IR, eGFR, change in BMI between baseline and follow-up	8
Huh et al., 2015 [14]	South Korea	Population-based; n = 1,521; age 40–70 y; 484 men; 124 baseline NAFLD; without baseline HTN; 153 incident HTN	Prospective cohort; 2.6 years	FLI ≥ 60	SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg or current use of antihypertensive agents	Association with incident HTN	Age, gender, baseline SBP, baseline DBP, smoking, regular exercise, alcohol intake, diabetes, log ALT, log HOMA-IR, hsCRP, serum creatinine, adiponectin	7
Ma et al., 2016 [8]	USA	Population-based; n = 1,051; mean age 45 y; 572 men; 187 baseline fatty liver; 82 baseline HTN	Prospective cohort; 6 years	CT	SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg or current use of antihypertensive agents	Association with incident HTN	Age, sex, baseline current smoking, physical activity, alcohol intake, SBP, DBP, VAT, delta VAT, delta LPR	7
						Association with incident fatty liver
Kim et al., 2017 [15]	South Korea	Population-based; n = 6,331; mean age 51y; 2,995 men; 1,517 baseline NAFLD; without baseline HTN; 891 incident HTN	Retrospective study; 8.7 years	FLI, hepatic steatosis index, and comprehensive NAFLD score; two or three indexes were satisfied	Blood pressure levels	Association with incident HTN	Age, gender, diabetes mellitus, family history of HTN and obesity	7
Liu et al., 2018 [9]	China	Population-based; 6,704 HTN-free subjects; 2,008 baseline NAFLD; 2,561 incident HTN; 9,328 NAFLD-free subjects; 4,436 baseline HTN; 2,289 incident NAFLD	Prospective cohort; 5 years	Liver ultrasound	SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg or current use of antihypertensive agents or prior diagnosis	Association with incident HTN	Age, sex, past history of CHD, family history of HTN, diabetes, BMI	9
						Association with incident NAFLD
Zhou and Cen, 2018 [16]	China	Population-based; n = 4,687; mean age 40 y; 3,177 men; 304 baseline NAFLD (FLI ≥ 60); without baseline HTN; 2,047 incident HTN	Prospective cohort; 9 years	FLI	SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg or current use of antihypertensive agents	Association with incident HTN	Age, gender, indicators of metabolic syndrome (waist circumference, SBP, DBP, FPG, HDL-C, TG)	8
Bonnet et al., 2017 [17]	France	Population-based; n = 2,565 (insulin resistance cohort); aged 30–65y; 1,138 men; 220 baseline NAFLD (FLI ≥60); without baseline HTN; 1,021 incident HTN	Prospective cohort; 9 years	FLI	SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg or current use of antihypertensive agents	Association with incident HTN	Age, sex, smoking, FPG, alcohol intake	7
Lau et al., 2010 [18]	Germany	Population-based; n = 3,191; 1,532 men; aged 20–79 years	Prospective cohort; 5.3 years	Liver ultrasound and AST	SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg or current use of antihypertensive agents	Association with incident HTN	Age, sex, waist circumference, BMI, diabetes mellitus, alcohol consumption, use of antihypertensive medication	8
Tsuneto et al., 2010 [10]	Japan	1,635 Nagasaki atomic bomb survivors; 606 men; without baseline fatty liver; 323 incident fatty liver	Retrospective cohort; 11.6 years	Liver ultrasound	SBP ≥ 130 mmHg and/or DBP ≥ 85 mmHg	Association with incident fatty liver	Age, sex, smoking and drinking habits, obesity, hypercholesterolemia, low HDL-C, hypertriglyceridemia, glucose intolerance, atomic radiation dose	7
Zhang et al., 2015 [11]	China	Population-based; n = 15,791; mean age 42.5 y; 7,922 men; 877 baseline HTN; without baseline NAFLD; 3,913 incident NAFLD	Prospective cohort; 3.3 years	Liver ultrasound	SBP ≥ 140 mmHg and/or DBP values ≥ 90 mmHg or prior diagnosis	Association with incident NAFLD	Age, gender, smoking status, diet, regular exercise	7

Abbreviations: HTN, hypertension; SBP, systolic blood pressure; DBP, diastolic blood pressure; NAFLD, non-alcoholic fatty liver disease; BMI, body mass index; FLI, fatty liver index; AST, aspartate aminotransferase; ALT, alanine aminotransferase; GGT, glutamyl transpeptidase; HDL-C, high-density lipoprotein cholesterol; hsCRP, high-sensitivity C-reactive protein; TG, triglyceride; FPG, fasting plasma glucose; HOMA-IR, homeostasis model assessment of insulin resistance; VAT, visceral adipose tissue; LPR, liver-phantom ratio; and CHD, coronary heart disease. The Newcastle–Ottawa Scale (NOS) was applied for the quality evaluation of cohort studies. The quality of each cohort study ranges from 1 to 9 points based on three domains: the cohort selection (maximum 4 points), the comparability of the cohort design and analysis (maximum 2 points), and the adequacy of the outcome measures (maximum 3 points). Studies achieving a score of at least seven points were considered high quality.