Table 3.

HRs of type 2 diabetes according to 4-year changes in dietary quality (categories in AHEI scores) stratified by categories of AHEI scores at the beginning of the 4-year period, pooled results of NHS (1986–2010), NHS II (1991–2011), and HPFS (1986–2010)^*

Initial diet quality scores	Diet quality change category 4 years later					P for trend	HR per 10% score increase
	Decrease		No change or stable (±<3%)	Increase
	Moderate to large (>10%)	Small to moderate (3–10%)		Small to moderate(3–10%)	Moderate to large (>10%)
Low (<45)	1.56 (1.18–2.06)	1.05 (0.92–1.20)	1.00	0.95 (0.86–1.04)	0.83 (0.75–0.93)	<0.0001	0.88 (0.84–0.93)
Medium (45–59)	1.13 (1.00–1.27)	0.99 (0.91–1.07)	1.00	0.93 (0.85–1.00)	0.90 (0.82–1.00)	0.001	0.93 (0.89–0.96)
High (≥60)	1.31 (1.14–1.50)	1.07 (0.94–1.21)	1.00	0.88 (0.76–1.02)	0.96 (0.78–1.18)	<0.0001	0.87 (0.82–0.92)

Values are reported as HR (95% CI), unless otherwise indicated.

*Adjusted for age; ethnicity (white/nonwhite); family history of diabetes (yes/no); baseline physical activity and total energy intake at the beginning of each 4-year period (all in quintiles); 4-year changes in smoking status (never to never, never to current, past to past, past to current, current to past, current to current, or missing indicator), physical activity, and total energy intake (all in quintiles); a medical history of hypertension (yes/no) and hypercholesterolemia (yes/no); and baseline BMI values at the beginning of each 4-year period. In the NHS and NHS II, postmenopausal status and postmenopausal hormone use (never use, current use, past use, or missing) were also included.