Table 4.

Relative risk of prostate cancer-specific and all-cause mortality according to post-diagnostic intakes of high-fat and low-fat dairy among men diagnosed with non-metastatic prostate cancer in the Physicians’ Health Study (n=926)

Total mortality	HR (95%CI)a	P value	P for differenceb
High-fat dairy (per serving/day)	1.22 (1.08, 1.38)	0.002	0.56
Low-fat dairy (per serving/day)	1.17 (1.05, 1.29)	0.003

Prostate cancer-specific mortality	HR (95 %CI)a	P value	P for differenceb
High-fat dairy (per serving/day)	1.30 (0.97, 1.73)	0.08	0.57
Low-fat dairy (per serving/day)	1.16 (0.88, 1.53)	0.28

HR = hazard ratio; CI = confidence interval.

^aHazard ratios were per-serving increase of dairy intake. Cox proportional hazards regression model adjusted for age at diagnosis (years, continuous), total energy intake (kcal, continuous), body mass index (kg/m², <25, ≥25 to < 30, ≥30), smoking status (never, past, current), vigorous exercise (yes, no), Gleason score (<7, 7, >7), clinical stage (T1/T2, T3), prostate-specific antigen level (ng/ml, <4, 4-9.9, 10-19.9, ≥20), time interval between diagnosis and FFQ completion (years, continuous), initial treatment after diagnosis (radiation, prostatectomy, others, unspecified or missing), family history of prostate cancer (yes, no) and indicators for prudent dietary pattern and western dietary pattern after excluding dairy products (continuous). High-fat dairy and low-fat dairy intakes were mutually adjusted.

^bP for difference was calculated by including linear terms for both food groupings in the same Cox model and testing the null hypothesis that there was no difference between these terms.