Table 4 Odds ratios (95% CI) of mixed/dense mammographic density by screening age, period, and birth cohort
From: Mammographic density in birth cohorts of Danish women: a longitudinal study
Copenhagen | N F/MD* | Crude odds ratio | Adjusted odds ratio | Funen | N F/MD* | Crude odds ratio | Adjusted odds ratio |
|---|---|---|---|---|---|---|---|
Age 2 | Age 2 | ||||||
50-51 | 2169|5649 | Ref. | Ref. | 50-51 | 5125|17997 | Ref | Ref |
52-53 | 5300|11508 | 0.87 (0.84-0.90) | 0.92 (0.89-0.95) | 52-53 | 6232|16045 | 0.82 (0.80-0.83) | 0.89 (0.86-0.91) |
54-55 | 5548|9414 | 0.78 (0.76-0.81) | 0.89 (0.85-0.92) | 54-55 | 6620|13886 | 0.74 (0.72-0.76) | 0.87 (0.85-0.90) |
56-57 | 5763|7783 | 0.71 (0.69-0.74) | 0.86 (0.82-0.90) | 56-57 | 6749|11790 | 0.68 (0.66-0.70) | 0.88 (0.85-0.91) |
58-59 | 5783|6672 | 0.67 (0.64-0.69) | 0.86 (0.82-0.90) | 58-59 | 6513|10263 | 0.64 (0.62-0.66) | 0.92 (0.89-0.95) |
60-61 | 6015|5992 | 0.62 (0.60-0.65) | 0.85 (0.81-0.90) | 60-61 | 6501|9163 | 0.60 (0.58-0.62) | 0.97 (0.93-1.02) |
62-63 | 6225|5533 | 0.59 (0.57-0.62) | 0.86 (0.82-0.90) | 62-63 | 6519|8215 | 0.58 (0.56-0.60) | 1.05 (1.00-1.10) |
64-65 | 6408|5219 | 0.55 (0.53-0.58) | 0.85 (0.80-0.89) | 64-65 | 6514|7306 | 0.56 (0.54-0.58) | 1.12 (1.07-1.17) |
66-67 | 6685|5201 | 0.54 (0.52-0.56) | 0.86 (0.81-0.91) | 66-67 | 6360|6705 | 0.56 (0.54-0.58) | 1.22 (1.16-1.29) |
68-69 | 6798|5211 | 0.53 (0.51-0.55) | 0.88 (0.83-0.93) | 68-69 | 6183|5979 | 0.54 (0.52-0.56) | 1.30 (1.23-1.37) |
70-71 | 3532|2662 | 0.50 (0.48-0.53) | 0.87 (0.81-0.92) | - | - | - | - |
Period 2 | Period 2 | ||||||
1991-1993 | 15814|14177 | Ref. | Ref. | 1994-1995 | 16100|22959 | Ref | Ref |
1993-1995 | 13092|12827 | 0.98 (0.96-1.00) | 0.95 (0.93-0.96) | 1996-1997 | 18031|24736 | 0.84 (0.83-0.86) | 0.81 (0.80-0.82) |
1995-1997 | 11668|13313 | 1.00 (0.98-1.02) | 0.94 (0.92-0.96) | 1998-1999 | 15733|27831 | 0.97 (0.96-0.99) | 0.91 (0.90-0.93) |
1997-1999 | 10669|14600 | 1.01 (0.99-1.04) | 0.92 (0.90-0.94) | 2000-2001 | 13452|31823 | 1.15 (1.13-1.18) | 1.05 (1.03-1.07) |
1999-2001 | 8983|15927 | 1.11 (1.08-1.13) | 0.97 (0.95-1.00) | - | - | - | - |
Birthcohort 1 | Birthcohort 1 | ||||||
1921-1922 | 1599|1117 | Ref. | Ref. | 1924-1925 | 1620|1401 | Ref. | Ref. |
1923-1924 | 3276|2334 | 1.02 (0.93-1.13) | 1.02 (0.93-1.13) | 1926-1927 | 3359|3008 | 1.01 (0.93-1.11) | 1.04 (0.96-1.14) |
1925-1926 | 4508|3258 | 1.04 (0.94-1.15) | 1.05 (0.95-1.16) | 1928-1929 | 4972|4721 | 1.10 (1.01-1.20) | 1.19 (1.09-1.30) |
1927-1928 | 5285|4026 | 1.11 (1.00-1.22) | 1.12 (1.01-1.24) | 1930-1931 | 6579|6518 | 1.21 (1.11-1.32) | 1.35 (1.24-1.48) |
1929-1930 | 6047|4746 | 1.13 (1.03-1.25) | 1.15 (1.04-1.28) | 1932-1933 | 6323|7672 | 1.42 (1.30-1.54) | 1.70 (1.55-1.86) |
1931-1932 | 6166|5315 | 1.26 (1.14-1.39) | 1.28 (1.15-1.42) | 1934-1935 | 6415|8665 | 1.54 (1.42-1.68) | 1.98 (1.81-2.17) |
1933-1934 | 5880|5270 | 1.32 (1.20-1.46) | 1.35 (1.21-1.50) | 1936-1937 | 6573|9729 | 1.77 (1.63-1.92) | 2.40 (2.19-2.63) |
1935-1936 | 5705|5888 | 1.51 (1.36-1.66) | 1.53 (1.37-1.70) | 1938-1939 | 6529|10507 | 1.99 (1.83-2.17) | 2.83 (2.58-3.11) |
1937-1938 | 5547|6556 | 1.71 (1.55-1.89) | 1.71 (1.53-1.90) | 1940-1941 | 6588|12407 | 2.20 (2.03-2.39) | 3.18 (2.90-3.50) |
1939-1940 | 5716|7490 | 1.91 (1.73-2.10) | 1.86 (1.67-2.07) | 1942-1943 | 6638|14842 | 2.76 (2.55-3.00) | 3.90 (3.54-4.28) |
1941-1942 | 4300|7531 | 2.56 (2.32-2.82) | 2.48 (2.22-2.76) | 1944-1945 | 4686|13950 | 3.27 (3.01-3.55) | 4.63 (4.21-5.10) |
1943-1944 | 3270|7371 | 3.27 (2.97-3.61) | 3.12 (2.80-3.48) | 1946-1947 | 2429|9351 | 4.23 (3.88-4.61) | 5.89 (5.32-6.51) |
1945-1946 | 2032|6151 | 4.40 (3.98-4.87) | 4.15 (3.71-4.64) | 1948-1949 | 875|4578 | 5.93 (5.37-6.55) | 7.68 (6.86-8.61) |
1947-1948 | 805|3400 | 6.21 (5.55-6.95) | 5.72 (5.05-6.47) | - | - | - | - |
1949-1950 | 90|391 | 6.22 (4.88-7.92) | 5.41 (4.22-6.94) | - | - | - | - |