Table 3.
Association between adherence to the Mediterranean diet and prevalence of hepatic steatosis, Fenland and CoLaus studies*
| Prevalence ratio (95% CI) across quintiles of pyramid-based Mediterranean diet score† | p trend | Prevalence ratio (95% CI) per SD difference† | |||||
|---|---|---|---|---|---|---|---|
| Q1 | Q2 | Q3 | Q4 | Q5 | |||
| Fenland Study | |||||||
| Range of scores | 3.30–7.84 | 7.85–8.73 | 8.74–9.46 | 9.47–10.28 | 10.29–14.03 | ||
| N total | 1929 | 1929 | 1929 | 1929 | 1929 | ||
| FLI, median (iqr)‡ | 47.6 (21.1, 76.4) | 39.6 (16.1, 69.7) | 30.6 (11.9, 61.3) | 25.3 (10.3, 55.4) | 16.9 (7.5, 42.2) | ||
| N cases (score ≥ 60) | 773 | 632 | 496 | 424 | 285 | ||
| Multivariable + SES + dietary factor§ | 1.00 (ref.) | 0.94 (0.84, 1.06) | 0.81 (0.71, 0.92) | 0.75 (0.65, 0.86) | 0.52 (0.44, 0.62) | < 0.001 | 0.82 (0.78, 0.86) |
| Multivariable + BMI‖ | 1.00 (ref.) | 1.00 (0.88, 1.12) | 0.98 (0.86, 1.12) | 0.94 (0.82, 1.08) | 0.76 (0.64, 0.89) | 0.001 | 0.94 (0.89, 0.98) |
| CoLaus Study | |||||||
| Range of scores | 1.83–7.45 | 7.46–8.18 | 8.19–8.82 | 8.83–9.47 | 9.48–12.18 | ||
| N total | 792 | 791 | 792 | 791 | 791 | ||
| FLI, median (iqr)‡ | 43.0 (19.0, 72.8) | 37.2 (14.9, 66.5) | 30.9 (13.2, 56.5) | 27.4 (11.7, 53.7) | 22.5 (9.4, 49.0) | ||
| N cases (score ≥ 60) | 297 | 240 | 170 | 160 | 135 | ||
| Multivariable + SES + dietary factor§ | 1.00 (ref.) | 0.93 (0.77, 1.12) | 0.74 (0.60, 0.90) | 0.73 (0.59, 0.90) | 0.61 (0.49, 0.77) | < 0.001 | 0.85 (0.80, 0.91) |
| Multivariable + BMI‖ | 1.00 (ref.) | 1.06 (0.87, 1.28) | 0.90 (0.74, 1.11) | 0.85 (0.69, 1.05) | 0.79 (0.63, 1.00) | 0.009 | 0.94 (0.88, 1.006) |
| NAFLD liver fat score, median (iqr)** | − 1.5 (− 2.3, − 0.2) | − 1.6 (− 2.3, − 0.4) | − 1.7 (− 2.4, − 0.7) | − 1.8 (− 2.4, − 0.8) | − 2.0 (− 2.5, − 0.8) | ||
| N cases (score ≥ − 0.640) | 257 | 240 | 181 | 168 | 172 | ||
| Multivariable + SES + dietary factor§ | 1.00 (ref.) | 1.03 (0.86, 1.25) | 0.84 (0.69, 1.03) | 0.82 (0.67, 1.01) | 0.85 (0.69, 1.05) | 0.022 | 0.93 (0.87, 0.99) |
| Multivariable + BMI‖ | 1.00 (ref.) | 1.08 (0.89, 1.30) | 0.92 (0.75, 1.12) | 0.88 (0.72, 1.09) | 1.02 (0.82, 1.26) | 0.50 | 0.98 (0.91, 1.04) |
FLI fatty liver index, iqr interquartile range, SES socio-economic status, BMI body mass index, NAFLD non-alcoholic fatty liver disease
*For this analysis, the outcome was assessed by fatty liver index and NAFLD liver fat score
**Calculated based on an algorithm including presence of the metabolic syndrome and type 2 diabetes and concentrations of fasting serum insulin, fasting serum aspartate-aminotransferase (AST), and AST/alanine-aminotransferase ratio
†In categorical analysis, the population was divided into five groups by quintiles (Q1-Q5) of the Mediterranean diet score, standard deviation is 1.43 and 1.24 for pyramid-based Mediterranean diet score in the Fenland and CoLaus studies, respectively
‡Calculated based on an algorithm including body mass index, waist circumference, triglycerides, and gamma-glutamyl transferase
§Adjusted for age (years), sex, marital status (single, married/cohabiting, and divorced/widowed), occupational status (routine and professional jobs in the Fenland Study and working and not working in the CoLaus Study), education level (compulsory, secondary, and university), smoking status (never, former, and current), energy intake (kcal/day), physical activity energy expenditure (kcal/day, in the Fenland Study), total energy expenditure (kcal/day—in the CoLaus Study), and date of dietary assessment (in the CoLaus Study)
‖Further adjusted for BMI. Results of further adjustment for waist circumference were broadly in line with of the further adjustment for BMI (data not shown)