Smoking is associated with severity of liver fibrosis but not with histological severity in nonalcoholic fatty liver disease. Results from a cross-sectional study

Figures & data

Table 1. Patient characteristics.

	Never smokers (n = 34)	Ever smokers (n = 22)	p value
Clinical features
Male	24 (70.6%)	14 (63.6%)	.586
Age	45.7 (±14.4)	54.2 (±12.9)	.028
BMI^a	31.2 (±5.6)	29.9 (±6.3)	.258
Obese (BMI >30)^a	13 (54.2%)	5 (35.7%)	.272
Type-2 DM^a	7 (21.9%)	8 (40.0%)	.160
Alcohol use (units/week)^b	0 (IQR 0–7)	7 (IQR 0–14)	.111
Histology
Fibrosis score according to Brunt	1 (IQR 1–1.5)	2 (IQR 0–3)	.040
No fibrosis (stage 0)	14 (41.2%)	6 (27.3%)	.099
Early fibrosis (stage 1–2)	15 (44.1%)	8 (36.3%)	.099
Advanced fibrosis (stage 3–4)	5 (14.7%)	8 (36.3%)	.099
NAFLD activity score (NAS) (0–8)	2.8 ± 1.5	3.3 ± 1.4	.205

Legend: Expressed as number and percentage for categorical variables, median (IQR) for ordinal variables and mean (±SD) for continuous variables.

^a BMI, Obese n = 38, Type-2 DM n = 52.

^b Median (IQR) is shown for alcohol use because of non-normal distribution and tested with a Mann–Whitney U-test.

Bold values are significant p-values (<0.05).

Figure 1. Number of pack years compared between patients with no-early (stage 0–2) and advanced fibrosis (stage 3–4). Panel A shows the difference in number of pack years (represented with boxplots with median, IQR and min–max value) for the whole cohort. Panel B shows the difference in number of pack years (represented as mean + standard error of the mean) for ever smokers (active and past smokers).

Figure 2. Number of pack years in patients with a NAS lower than 5 compared to patients with a NAS of 5 or higher. Panel A shows the difference in number of pack years (represented with boxplots with median, IQR and min–max value) for the whole cohort. Panel B shows the difference in number of pack years (represented as mean + standard error of the mean) for ever smokers (active and past smokers).