Table 2

Long-term diet quality and risk of type 2 diabetes in the SWHS and SMHS (1996–2015)

Quintile of the HDS*Pcontinuous
Q1 (low)Q2Q3Q4Q5 (high)
Women
 HDS, median18.021.824.027.031.0
 No. of cases/person-years841/170,119769/178,845673/179,417645/184,155552/171,427
 Age- and energy-adjusted1.00 (ref.)0.90 (0.82–0.99)0.83 (0.75–0.92)0.80 (0.72–0.89)0.72 (0.65–0.81)<0.0001
 Multivariable-adjusted1.00 (ref.)0.93 (0.84–1.03)0.88 (0.79–0.97)0.86 (0.77–0.95)0.80 (0.71–0.89)<0.0001
 Multivariable- and BMI-adjusted1.00 (ref.)0.97 (0.88–1.07)0.92 (0.83–1.02)0.90 (0.81–1.00)0.85 (0.76–0.95)<0.0001
Men
 HDS, median18.021.524.027.031.0
 No. of cases/person-years542/88,724580/97,378527/93,180528/96,757454/95,156
 Age- and energy-adjusted1.00 (ref.)0.98 (0.87–1.10)0.93 (0.82–1.04)0.89 (0.79–1.01)0.78 (0.68–0.88)<0.0001
 Multivariable-adjusted1.00 (ref.)1.01 (0.90–1.14)0.98 (0.87–1.11)0.98 (0.86–1.11)0.86 (0.76–0.99)0.003
 Multivariable- and BMI-adjusted1.00 (ref.)1.02 (0.91–1.15)0.99 (0.88–1.12)0.98 (0.86–1.10)0.85 (0.74–0.97)0.002
Pooled
 HDS, median18.021.524.027.031.0
 No. of cases/person-years1,383/258,8431,349/276,2231,200/272,5971,173/280,9121,006/266,583
 Age- and energy-adjusted1.00 (ref.)0.93 (0.86–1.00)0.87 (0.80–0.94)0.84 (0.78–0.91)0.74 (0.69–0.81)<0.0001
 Multivariable-adjusted1.00 (ref.)0.96 (0.89–1.04)0.92 (0.85–1.00)0.91 (0.84–0.98)0.83 (0.76–0.90)<0.0001
 Multivariable- and BMI-adjusted1.00 (ref.)0.99 (0.92–1.07)0.95 (0.88–1.02)0.93 (0.86–1.01)0.85 (0.78–0.92)<0.0001
  • Data are HR (95% CI) unless otherwise stated. ref., reference.

  • *Cumulative average of the HDS based on data from repeated FFQs.

  • †The Cox model was stratified by follow-up periods and adjusted for total energy intake, education, income, smoking, alcohol drinking, leisure-time exercise, family history of diabetes, history of hypertension, history of dyslipidemia, and, in women, menopausal status. Information on smoking, alcohol drinking, physical activity, hypertension, dyslipidemia, BMI, and menopausal status was updated during follow-up and modeled as time-varying variables.

  • ‡Results among women and men were combined using fixed-effect meta-analysis, given that there was no significant heterogeneity by sex.