Table 3.
Mean Differences (and 95% Confidence Intervals) in HDL‐C Change Rate From 2006 to 2012 by Tea Type and Consumption in 2006a
| Tea Consumption | P for Trend | ||||
|---|---|---|---|---|---|
| Never or Less Than Once/Month | 1 to 3 Times/Month | 1 to 3 Times/Week | ≥4 Times/Week | ||
| Black tea | |||||
| N | 79 450 | 282 | 194 | 256 | |
| Change in HDL‐C | 0 (ref) | 0.006 (−0.002, 0.015) | 0.008 (−0.004, 0.019) | 0.013 (0.003, 0.023) | 0.002 |
| Change in TG/HDL‐C ratio | 0 (ref) | −0.028 (−0.055, −0.001) | −0.009 (−0.043, 0.025) | −0.049 (−0.073, −0.025) | <0.0001 |
| Change in TC/HDL‐C ratio | 0 (ref) | −0.016 (−0.040, 0.009) | −0.004 (−0.044, 0.035) | −0.025 (−0.053, 0.003) | 0.07 |
| Green tea | |||||
| N | 75 885 | 1344 | 1143 | 1810 | |
| Change in HDL‐C | 0 (ref) | 0.014 (0.010, 0.019) | 0.014 (0.009, 0.019) | 0.013 (0.009, 0.017) | <0.0001 |
| Change in TG/HDL‐C ratio | 0 (ref) | −0.002 (−0.021, 0.016) | 0.008 (−0.027, 0.042) | −0.025 (−0.043, −0.007) | 0.07 |
| Change in TC/HDL‐C ratio | 0 (ref) | −0.017 (−0.030, −0.005) | −0.014 (−0.033, 0.005) | −0.025 (−0.036, −0.013) | <0.0001 |
| Other tea | |||||
| N | 69 669 | 3096 | 2475 | 4942 | |
| Change in HDL‐C | 0 (ref) | 0.008 (0.004, 0.012) | 0.003 (−0.0004, 0.006) | 0.007 (0.004, 0.011) | <0.0001 |
| Change in TG/HDL‐C ratio | 0 (ref) | 0.009 (−0.008, 0.025) | 0.023 (−0.012, 0.059) | −0.011 (−0.030, 0.007) | 0.81 |
| Change in TC/HDL‐C ratio | 0 (ref) | 0.015 (−0.036, 0.066) | −0.0003 (−0.018, 0.017) | −0.009 (−0.020, 0.001) | 0.38 |
HDL‐C indicates high‐density lipoprotein cholesterol; LDL‐C, low‐density lipoprotein cholesterol; TC, total cholesterol; and TG, triglyceride.
All models adjusted age, sex (men or women), education (illiterate, middle, or college), income (<600, 600–1000, or >1000 RMB/month), occupation (white collar, coal miner, or other blue collar), physical activity (inactive, moderate, or active), smoking status (never, past, or current), alcohol drinking status (never, past, or current), blood glucose status (normoglycemia, impaired fasting blood glucose, or hyperglycemia), blood pressure status (normotensive, prehypertension, or hypertension), body mass index (in kg/m2; <24, 24–27.9, 28–29.9, or ≥30), waist circumference (<85 or ≥85 cm for women, and <90 or ≥90 cm for men), C‐reactive protein (<1, 1–2.9, or ≥3 mg/L), fatty liver (none, mild, or severe). Models were further adjusted for TG and LDL‐C for change in HDL‐C, for TG for change in TC/HDL‐C ratio, for LDL‐C for change in TG/HDL ratio. Generalized estimating equation models were used to model change rates and to test differences in change rates compared with the never or less than once/month group.