Table 3.
Clinical variables according to tea consumption status (i.e., none vs. former vs. current consumers).
| Variable | Category | Non- consumers (N = 134) | Former tea consumers (N = 6) | Current tea consumers (N = 101) | Comparisons ( p -values) | |||
|---|---|---|---|---|---|---|---|---|
| Overall | Former consumers vs. non-consumers | Current consumers vs. non-consumers | Current consumers vs. former-consumers | |||||
| Country—N (%) | Italy | 128 (95.5) | 6 (100.0) | 72 (71.3) | <0.001 | 1.000 | <0.001 | 0.187 |
| Moldova/ Romania | 6 (4.5) | 0 (0.0) | 29 (28.7) | |||||
| Gender—N (%) | Males | 87 (64.9) | 2 (33.3) | 56 (55.4) | 0.154 | 0.190 | 0.177 | 0.409 |
| Females | 47 (35.1) | 4 (66.7) | 45 (44.6) | |||||
| BMI at interview—N (%) | <18.5 | 6 (4.5) | 1 (16.7) | 8 (7.9) | 0.123 | 0.423 | 0.097 | 0.333 |
| 18.5–24.9 | 62 (46.3) | 2 (33.3) | 57 (56.4) | |||||
| ≥25 | 66 (49.3) | 3 (50.0) | 36 (35.6) | |||||
| Age at interview (years) | Mean ± SD | 64.2 ± 10.5 | 55.7 ± 13.0 | 60.4 ± 11.1 | 0.009 | 0.058 | 0.007 | 0.300 |
| Age at onset (years) | Mean ± SD | 61.5 ± 11.1 | 51.9 ± 14.1 | 58.3 ± 12.2 | 0.028 | 0.048 | 0.038 | 0.188 |
| Diagnostic delay (years)# | Median (range) | 0.9 [0.1–15.8] | 0.8 [0.2–3.0] | 0.8 [0.1–9.3] | 0.588 | 0.657 | 0.326 | 0.895 |
| Education (years) | Mean ± SD | 10.2 ± 4.7 | 11.7 ± 4.7 | 10.7 ± 3.9 | 0.521 | 0.419 | 0.362 | 0.605 |
| Age at start tea (green or black) consuming (years) | Mean ± SD | — | 24.8 ± 13.6 | 23.8 ± 18.5 | 0.893 | — | — | 0.893 |
| Duration of black tea consumption (years)# | Median (range) | — | 12.0 [0.0–31.0] | 35.0 [0.0–70.0] | 0.143 | — | — | 0.143 |
| Duration of green tea consumption (years)# | Median (range) | — | 2.0 [0.0–45.0] | 2.0 [0.0–64.0] | 0.849 | — | — | 0.849 |
| Lifetime intensity of black tea consumption—N (%) | 0 cups/day* | — | 3 (50.0) | 24 (23.8) | 0.265 | — | — | 0.265 |
| 1–2 cups/day* | 3 (50.0) | 75 (74.3) | ||||||
| 3–4 cups/day* | 0 (0.0) | 2 (2.0) | ||||||
| Lifetime intensity of green tea consumption—N (%) | 0 cups/day* | — | 3 (50.0) | 48 (47.5) | 1.000 | — | — | 1.000 |
| 1–2 cups/day* | 3 (50.0) | 51 (50.5) | ||||||
| 3–4 cups/day* | 0 (0.0) | 2 (2.0) | ||||||
| Black tea load (cup-years)#, § | Median (range) | — | 14.0 [0.0–58.0] | 50.0 [0.0–187.9] | 0.152 | — | — | 0.152 |
| Green tea load (cup-years)#, § | Median (range) | — | 4.0 [0.0–89.9] | 4.0 [0.0–187.9] | 0.926 | — | — | 0.926 |
| Tea intensity (green or black) at interview (cups/day) | 1–2 cups/day | — | — | 93 (92.1) | — | — | — | — |
| 3–4 cups/day | 8 (7.9) | |||||||
| ΔFS# | Median (range) | 0.6 [0.0–5.3] | 0.5 [0.0–4.3] | 0.6 [0.0–4.2] | 0.639 | 0.356 | 0.931 | 0.345 |
Missing values were excluded from the analysis and percentages were computed out of the total number of observations. SD, standard deviation; p-values from ANOVA models or Fisher exact test for continuous and categorical variables, respectively.
log-transformed variable was used in the ANOVA model.
The cup-years is the unit for measuring the amount a person has consumed over a long period of time and it was computed by dividing the cumulative lifetime exposure load by 365.25 units.
Lifetime intensity of tea consumption was computed as the weighted mean of the number of cups consumed per day at different age periods, with weights equal to the duration of tea consumption within each age period. Tea intensity at the interview is the number of cups/day drunk at the time of the interview.