Nonalcoholic fatty liver disease and its prognosis associates with shorter leucocyte telomeres in a 21-year follow-up study

Figures & data

Figure 1. Proportion of NAFLD in each telomere tertile. Tertile one represents the shortest telomeres and tertile three the longest telomeres. The unadjusted univariate analysis of proportion of NAFLD in each tertile showed statistically significant difference when comparing the shortest telomere tertile against other tertiles. Reference category was selected to be the tertile with longer telomeres. Multivariate model adjusting for age, sex, BMI, CHD, LDL, HOMA-IR and TM6SF2 as follows: Tertile 1 vs. 3: p = .007 HR 2.03 (95% CI 1.22–3.38); Tertile 1 vs. 2: p = .006 HR 1.98 (95% CI 1.22–3.23); Tertile 2 vs. 3: p = .636 HR 1.13 (95% CI 0.68–1.87). CI: confidence interval; BMI: body mass index; CHD: coronary heart disease; LDL: low-density lipoproteins; HOMA-IR: homeostatic model of assessment of insulin resistance; TM6SF2: transmembrane 6 superfamily member 2.

Table 1. Characteristics of the study population according to telomere length.

	Tertile 1 (n = 282) mean ± standard error	Tertile 2 (n = 283) mean ± standard error	Tertile 3 (n = 282) mean ± standard error	p For trend
Demographics and traits
Male (%)	37.0	41.3	61.0	<.001
Age (years)	53.6 ± 0.3	51.9 ± 0.4	48.9 ± 0.3	<.001
BMI (kg/m^2)	28.2 ± 0.3	27.7 ± 0.3	27.2 ± 0.3	.017
Waist (cm)	89.7 ± 0.8	89.4 ± 0.8	90.8 ± 0.8	.322
Smoking (pack-years)	9.0 ± 0.9	8.4 ± 0.8	10.2 ± 0.8	.295
Diseases
Hypertension (%)	55.7	47.0	50.0	.178
CHD (%)	13.5	9.5	3.9	<.001
Diabetes (%)	11.7	10.2	8.2	.161
NAFLD (%)	34.4	24.0	20.9	<.001
Liver tests, lipids, insulin resistance and NAFLD genetics
ALT (U/l)	31.1 ± 1.1	30.0 ± 2.4	31.9 ± 1.4	.617
GGT (U/l)	45.2 ± 1.4	40.4 ± 1.4	40.6 ± 1.4	.300
LDL (mmol/l)	3.6 ± 0.1	3.5 ± 0.1	3.4 ± 0.1	.038
Triglycerides (mmol/l)	1.6 ± 0.6	1.5 ± 0.6	1.5 ± 0.5	.407
HDL (mmol/l)	1.4 ± 0.2	1.4 ± 0.2	1.3 ± 0.2	.070
Total cholesterol (mmol/l)	5.8 ± 0.1	5.7 ± 0.1	5.5 ± 0.1	.012
HOMA-IR	3.4 ± 0.2	3.0 ± 0.2	2.7 ± 0.1	.032
NAFLD risk allele carriers
PNPLA3 rs738409 (%)	34.9	31.0	34.0	.848
MBOAT7 rs58542926 (%)	33.7	33.6	32.7	.161
TM6SF2 rs641738 (%)	22.3	40.8	36.9	.038

BMI: body mass index; CHD: coronary heart disease; NAFLD: non-alcoholic fatty liver disease; LDL: low-density lipoprotein; HDL: high-density lipoprotein; HOMA-IR: homeostatic model assessment of insulin resistance; ALT: alanine aminotransferase; GGT: gamma-glutamyltransferase; PNPLA3: patatin-like phospholipase domain-containing protein 3; MBOAT07: membrane-bound O-acyltransferase domain-containing protein 7; TM6SF2: transmembrane 6 superfamily member 2

Telomere tertile 1 has the shortest telomeres as opposite to tertile 3 with the longest telomeres.

Table 2. Cox regression analysis for the hazard of death for the whole study group.

	Univariate HR (95% CI)	p Value	Multivariate HR (95% CI)	p Value
Demographics, obesity and tobacco
Age	1.07 (1.04–1.10)	<.001	1.05 (1.02–1.08)	<.001
Sex	1.85 (1.38–2.50)	<.001	1.09 (0.66–1.79)	.732
MBO	2.11 (1.58–2.82)	<.001	1.33 (0.89–1.99)	.158
BMI	1.04 (1.01–1.07)	.006	0.96 (0.89–1.03)	.230
Waist	1.03 (1.02–1.04)	<.001	1.03 (1.02–1.05)	.290
Tobacco (pack years)	1.03 (1.02–1.04)	<.001	1.03 (1.02–1.04)	<.001
Diseases
Hypertension	1.22 (0.92–1.64)	.171	–	–
NAFLD	1.67 (1.24–2.26)	.001	0.93 (0.64–1.34)	.696
CHD	2.32 (1.57–3.43)	<.001	1.56 (1.02–2.38)	.040
Diabetes	2.88 (2.02–4.10)	<.001	2.27 (1.50–3.45)	<.001
History of stroke	5.63 (2.97–10.66)	<.001	3.76 (1.92–7.37)	<.001
Laboratory parameters
LTL	0.41 (0.20–0.84)	.014	0.67 (0.30–1.49)	.327
GGT	1.003 (1.002–1.005)	<.001	1.002 (1.000–1.004)	.022
ALT	1.009 (1.005–1.013)	<.001	1.001 (0.995–1.007)	.818
LDL	1.09 (0.93–1.26)	.286	–	–

HR: hazard ratio; CI: confidence interval; NAFLD: non-alcoholic fatty liver disease; CHD: coronary heart disease; BMI: body mass index; MBO: metabolic syndrome; LTL: leucocyte telomere length; GGT: gamma-glutamyltransferase; ALT: alanine aminotransferase; LDL: low-density lipoprotein.

Reference category for sex was female. For MBO international diabetes federation diagnostic criteria (year 2005) were used.

Table 3. Cox regression analysis for hazard of death in non-NAFLD and NAFLD subjects.

Non-NAFLD subjects	Univariate HR (95% CI)	p Value	Multivariate HR (95% CI)	p Value
Demographics, obesity and tobacco
Age	1.07 (1.04–1.10)	<.001	1.05 (1.01–1.09)	.007
Sex	1.98 (1.37–2.86)	<.001	1.32 (0.81–2.16)	.272
MBO	1.85 (1.27–2.71)	.001	1.36 (0.83–2.23)	.227
BMI	1.04 (0.99–1.08)	.108	–	–
Waist	1.03 (1.01–1.04)	<.001	1.00 (0.97–1.02)	.720
Tobacco (pack years)	1.04 (1.03–1.05)	<.001	1.03 (1.02–1.04)	<.001
Diseases
Hypertension	0.91 (0.63–1.31)	.607	–	–
CHD	2.66 (1.61–4.40)	<.001	1.67 (0.96–2.89)	.069
Diabetes	2.98 (1.56–5.71)	.001	1.95 (0.93–4.09)	.080
History of stroke	5.06 (2.22–11.53)	<.001	3.21 (1.30–7.89)	.011
Laboratory parameters				–
LTL	0.73 (0.32–1.70)	.471	–
GGT	1.006 (1.002–1.011)	.003	1.004 (0.999–1.009)	.148
ALT	1.005 (0.997–1.013)	.217	–	–
LDL	1.175 (0.971–1.422)	.097	–	–
NAFLD subjects	Univariate HR (95% CI)	p Value	Multivariate HR (95% CI)	p Value
Demographics, obesity and tobacco
Age	1.07 (1.02–1.12)	.002	1.06 (1.00–1.12)	.042
Sex	1.38 (0.83–2.30)	.214	–	–
MBO	2.28 (1.16–4.46)	.016	1.29 (0.60–2.74)	.514
BMI	1.01 (0.96–1.06)	.786	–	–
Waist	1.02 (1.00–1.04)	.034	1.01 (0.99–1.04)	.366
Tobacco (pack years)	1.02 (1.01–1.04)	.003	1.02 (1.01–1.04)	.008
Diseases
Hypertension	0.96 (0.56–1.64)	.869	–	–
CHD	1.64 (0.88–3.06)	.123	–	–
Diabetes	2.34 (1.44–3.80)	.001	2.20 (1.25–3.87)	.006
History of stroke	7.36 (2.66–20.37)	<.001	6.31 (2.06–19.32)	.001
Laboratory parameters
LTL	0.16 (0.04–0.61)	.007	0.20 (0.04–0.98)	.045
GGT	1.002 (1.000–1.004)	.014	1.002 (0.999–1.004)	.163
ALT	1.009 (1.002–1.017)	.009	1.006 (0.996–1.015)	.236
LDL	0.91 (0.72 − 1.16)	.461	–	–

HR: hazard ratio; CI: confidence interval; NAFLD: non-alcoholic fatty liver disease; CHD: coronary heart disease; BMI: body mass index; MBO: metabolic syndrome; LTL: leucocyte telomere length.

Reference category for sex was female; GGT: gamma-glutamyltransferase; ALT: alanine aminotransferase; LDL: low-density lipoprotein.

For MBO international diabetes federation diagnostic criteria (year 2005) were used. For multivariate analysis, we accepted covariates that were statistically significant factors for hazard of death in univariate analysis in each subgroup.

Figure 2. Kaplan–Meier plot for hazard of death according to telomere tertiles in both NAFLD and non-NAFLD populations. For NAFLD the risk of death was statistically lower in the longest segment whereas of non-NAFLD the middle segment was of lowest risk. NAFLD: nonalcoholic fatty liver disease.