Background and aims

Nonalcoholic fatty liver disease (NAFLD) subjects with fibrosis stage ≥2 are at high risk for mortality. We aimed to provide national estimates and temporal trends for NAFLD, based on different fibrosis severity.

Methods

Data from the National Health and Nutrition Examination Survey (NHANES) (1999–2016) and NHANES III (1988–1994) were utilized. NAFLD was determined by ultrasound showing moderate to severe steatosis. For those without ultrasound, NAFLD was determined by the U.S. Fatty Liver Index score of ≥30. Hepatic fibrosis was assessed using Fibrosis-4 (FIB-4) score (FIB-4 <1.3 = low risk; FIB-4 1.3–2.67 = moderate risk; and FIB-4 >2.67 = high risk). Annual percent change (APC) was calculated by using the joinpoint regression model.

Results

From NHANES III, 10,854 individuals were included (mean age 43.5 years; 47.5% male; 75.7% non-Hispanic White) and 37.7% had NAFLD. Among them, based on FIB-4, 80% had low-risk, 18.6% had moderate-risk, and 1.4% had high-risk NAFLD. NAFLD with moderate or high risk was more likely to have hypertension, hyperlipidemia, diabetes, cardiovascular disease, and metabolic syndrome than was low-risk NAFLD (all P < .02). NAFLD prevalence increased from 29.5% in 1999–2000 to 40.3% in 2015–2016 (APC, 2.78%; P < .02), moderate-risk NAFLD increased from 6.26% to 14.17% (APC, 5.34%; P < .02), and high-risk NAFLD increased from 0.49% to 1.15% (APC, 9.72%; P < .02). Independent predictors of advanced fibrosis were age (OR, 1.11; 95% CI, 1.06–1.17; P = .001) and diabetes (OR, 2.28; 95% CI, 1.03–5.05; P = .04). Compared with low-risk NAFLD, high-risk NAFLD was associated with significantly increased all-cause (HR, 1.53; 95% CI, 1.09–2.15; P = .01), cardiovascular disease–specific (HR, 1.99; 95% CI, 1.22–3.24, P < .01) and liver-specific (HR, 4.57; 95% CI, 1.03–28.79; P = .04) mortality.

Conclusions

The prevalence of moderate- or high-risk NAFLD is increasing and is associated with increased all-cause, liver-related, and cardiovascular mortality.

中文翻译：

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1999-2016 年美国成年人中高风险和中度风险非酒精性脂肪肝的患病率

背景和目标

纤维化分期≥2 的非酒精性脂肪性肝病 (NAFLD) 受试者死亡风险高。我们旨在根据不同的纤维化严重程度提供 NAFLD 的国家估计和时间趋势。

方法

使用了来自国家健康和营养检查调查 (NHANES)（1999-2016 年）和 NHANES III（1988-1994 年）的数据。NAFLD 由显示中度至重度脂肪变性的超声确定。对于未接受超声检查的患者，NAFLD 由美国脂肪肝指数评分≥30 确定。使用 Fibrosis-4 (FIB-4) 评分评估肝纤维化（FIB-4 <1.3 = 低风险；FIB-4 1.3–2.67 = 中度风险；FIB-4 >2.67 = 高风险）。使用连接点回归模型计算年度百分比变化 (APC)。

结果

NHANES III 纳入了 10,854 人（平均年龄 43.5 岁；47.5% 为男性；75.7% 为非西班牙裔白人），其中 37.7% 患有 NAFLD。其中，基于FIB-4，80%为低危，18.6%为中危，1.4%为高危NAFLD。与低风险 NAFLD 相比，具有中度或高风险的 NAFLD 更可能患有高血压、高脂血症、糖尿病、心血管疾病和代谢综合征（所有P < .02）。NAFLD 患病率从 1999-2000 年的 29.5% 增加到 2015-2016 年的 40.3% (APC, 2.78%; P < .02)，中度风险 NAFLD 患病率从 6.26% 增加到 14.17% (APC, 5.34%; P < .02 ) )，高风险 NAFLD 从 0.49% 增加到 1.15%（APC，9.72%；P < .02）。晚期纤维化的独立预测因子是年龄（OR，1.11；95% CI，1.06–1.17；P = .001) 和糖尿病 (OR, 2.28; 95% CI, 1.03–5.05; P = .04)。与低风险 NAFLD 相比，高风险 NAFLD 与全因（HR，1.53；95% CI，1.09–2.15；P = .01）、心血管疾病特异性（HR，1.99；95% CI）显着增加相关, 1.22–3.24, P < .01) 和肝脏特异性 (HR, 4.57; 95% CI, 1.03–28.79; P = .04) 死亡率。

结论

中度或高风险 NAFLD 的患病率正在增加，并且与全因、肝脏相关和心血管死亡率增加有关。