Table 3.
Relative Risks (RR) for invasive malignant melanoma (IMM) Among whites and non-whites/multiracials recruited to the Multiethnic Cohort Study, 1993–1996
| Characteristics | whites | non-whites/multiracials | p-heterogeneityc | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| ca | RR | 95% CIa | RR | 95% CIb | ca | RR | 95% CIa | RR | 95% CIb | ||
| Study Site | |||||||||||
| California | 70 | 1.00 | 1.00 | 45 | 1.00 | 1.00 | |||||
| Hawaii | 402 | 2.42 | (1.97, 2.98) | 2.01 | (1.55, 2.60) | 52 | 1.75 | (0.89, 3.43) | 1.82 | (0.93, 3.60) | |
| P-value | <0.001 | <0.001 | 0.107 | 0.083 | 0.600 | ||||||
| Sex | |||||||||||
| Male | 286 | 1.00 | 1.00 | 62 | 1.00 | 1.00 | |||||
| Female | 186 | 0.62 | (0.53, 0.74) | 0.59 | (0.49, 0.71) | 35 | 0.52 | (0.34, 0.78) | 0.47 | (0.31, 0.72) | |
| P-value | <0.001 | <0.001 | 0.002 | 0.001 | 0.582 | ||||||
| Education | |||||||||||
| ≤ High school | 61 | 1.00 | 1.00 | 42 | 1.00 | 1.00 | |||||
| Some college | 137 | 2.70 | (2.10, 3.46) | 1.63 | (1.20, 2.21) | 34 | 1.85 | (1.16, 2.96) | 1.79 | (1.12, 2.87) | |
| ≥ College | 274 | 4.40 | (3.49, 5.56) | 2.08 | (1.57, 2.77) | 21 | 1.74 | (1.00, 3.02) | 1.60 | (0.91, 2.80) | 0.472 |
| P-trend | <0.001 | <0.001 | 0.019 | 0.046 | |||||||
| Age | |||||||||||
| 1 year increase | 1.04 | (1.03, 1.05) | 1.03 | (1.02, 1.05) | 1.06 | (1.03, 1.09) | 1.06 | (1.03, 1.08) | |||
| P-value | <0.001 | <0.001 | <0.001 | <0.001 | 0.062 | ||||||
| Hair color | |||||||||||
| Black/Medium dark brown | 208 | 1.00 | 1.00 | 77 | 1.00 | 1.00 | |||||
| Light brown | 161 | 1.68 | (1.37, 2.06) | 1.57 | (1.28–1.93) | 16 | 2.56 | (1.46, 4.50) | 2.33 | (1.32, 4.11) | |
| Blonde | 79 | 1.58 | (1.22, 2.05) | 1.40 | (1.08, 1.82) | 2 | 3.17 | (0.77, 13.1) | 2.61 | (0.63, 10.8) | |
| Red | 24 | 2.23 | (1.46, 3.40) | 1.73 | (1.13, 2.65) | 2 | 6.39 | (1.55, 26.4) | 5.12 | (1.23, 21.4) | |
| P-trend | <0.001 | <0.001 | <0.001 | <0.001 | 0.016 | ||||||
| Eye color | |||||||||||
| Dark (black/dark brown) | 138 | 1.00 | 1.00 | 76 | 1.00 | 1.00 | |||||
| Light (blue, grey, and green) | 334 | 1.51 | (1.24, 1.85) | 1.34 | (1.09, 1.64) | 21 | 3.39 | (2.03, 5.66) | 2.99 | (1.76, 5.06) | |
| P-value | <0.001 | 0.005 | <0.001 | <0.001 | 0.005 | ||||||
| Tanning ability | |||||||||||
| Deeply | 79 | 1.00 | 1.00 | 20 | 1.00 | 1.00 | |||||
| Moderately | 271 | 1.44 | (1.12, 1.84) | 1.33 | (1.03, 1.71) | 56 | 1.59 | (0.95, 2.66) | 1.59 | (0.95, 2.66) | |
| Lightly | 106 | 2.05 | (1.53, 2.75) | 1.69 | (1.26, 2.27) | 21 | 2.36 | (1.26, 4.40) | 2.37 | (1.27, 4.42) | |
| Not at all | 16 | 2.68 | (1.56, 4.60) | 2.07 | (1.20, 3.57) | 0 | -- | 0.803 | |||
| P-trend | <0.001 | <0.001 | 0.071 | 0.066 | |||||||
| Skin reaction to sunlight | |||||||||||
| No effect, or tans | 51 | 1.00 | 1.00 | 36 | 1.00 | 1.00 | |||||
| Mild burn, then tans | 233 | 1.79 | (1.32, 2.43) | 1.55 | (1.14, 2.11) | 47 | 1.52 | (0.98, 2.36) | 1.43 | (0.92, 2.23) | |
| Severe burns without blistering | 129 | 2.61 | (1.89, 3.62) | 2.03 | (1.45, 2.83) | 10 | 1.44 | (0.71, 2.92) | 1.21 | (0.59, 2.49) | |
| Severe burning with blistering | 59 | 2.42 | (1.66, 3.53) | 1.73 | (1.17, 2.55) | 4 | 1.38 | (0.49, 3.90) | 1.00 | (0.34, 2.93) | |
| P-trend | <0.001 | 0.001 | 0.152 | 0.51 | 0.362 | ||||||
| Sunburn susceptibility phenotype index | |||||||||||
| 0–1 | 40 | 1.00 | 1.00 | 26 | 1.00 | 1.00 | |||||
| 2–3 | 163 | 1.59 | (1.12, 2.24) | 1.44 | (1.02, 2.04) | 56 | 2.13 | (1.33, 3.40) | 2.06 | (1.29, 3.30) | |
| 4–5 | 161 | 2.20 | (1.56, 3.12) | 1.81 | (1.27, 2.57) | 10 | 2.68 | (1.28, 5.64) | 2.3 | (1.07, 4.92) | |
| 6–7 | 77 | 2.86 | (1.95, 4.20) | 2.13 | (1.44, 3.16) | 4 | 7.75 | (2.66, 22.6) | 5.82 | (1.92, 17.6) | |
| >7 | 31 | 4.35 | (2.71, 6.98) | 2.97 | (1.84, 4.82) | 1 | 15.8 | (2.10, 118) | 10.3 | (1.32, 80.4) | |
| P-trend | <0.001 | <0.001 | <0.001 | <0.001 | 0.048 | ||||||
| Ever-sunburned d | |||||||||||
| No | 113 | 1.00 | 1.00 | 63 | 1.00 | 1.00 | |||||
| Yes | 359 | 1.87 | (1.51, 2.31) | 1.52 | (1.22, 1.89) | 34 | 1.56 | (1.02, 2.38) | 1.26 | (0.81, 1.98) | |
| P-value | <0.001 | <0.001 | 0.04 | 0.305 | 0.655 | ||||||
| Lifetime number of sunburns d,e | |||||||||||
| No sunburn | 119 | 1.00 | 1.00 | 63 | 1.00 | 1.00 | |||||
| ≤ 3 sunburns | 216 | 1.70 | (1.36, 2.13) | 1.45 | (1.15, 1.82) | 21 | 1.42 | (0.86, 2.34) | 1.18 | (0.71, 1.98) | |
| >3 sunburns | 137 | 1.95 | (1.52, 2.50) | 1.45 | (1.12, 1.88) | 13 | 2.04 | (1.11, 3.76) | 1.6 | (0.85, 3.01) | |
| P-trend | <0.001 | 0.004 | 0.014 | 0.148 | 0.711 | ||||||
| First age of sunburn d,e | |||||||||||
| Never sunburned | 120 | 1.00 | 1.00 | 63 | 1.00 | 1.00 | |||||
| <13 years | 110 | 2.31 | (1.78, 3.00) | 1.69 | (1.28, 2.22) | 5 | 1.67 | (0.67, 4.21) | 1.18 | (0.45, 3.08) | |
| 13 to 17 years | 96 | 1.71 | (1.31, 2.24) | 1.39 | (1.05, 1.83) | 8 | 1.68 | (0.79, 3.53) | 1.35 | (0.63, 2.87) | |
| ≥ 18 years | 146 | 1.54 | (1.21, 1.97) | 1.35 | (1.06, 1.72) | 21 | 1.56 | (0.95, 2.57) | 1.31 | (0.79, 2.19) | |
| P-trend | 0.003 | 0.068 | 0.046 | 0.25 | 0.720 | ||||||
| Family history of melanoma d | |||||||||||
| No | 458 | 1.00 | 1.00 | 96 | 1.00 | 1.00 | |||||
| Yes | 14 | 2.47 | (1.45, 4.21) | 2.04 | (1.19, 3.48) | 1 | 3.27 | (0.45, 23.64) | 2.55 | (0.35, 18.7) | |
| P-value | 0.001 | 0.009 | 0.241 | 0.357 | 0.808 | ||||||
| History of non-melanoma skin cancer d | |||||||||||
| No | 337 | 1.00 | 1.00 | 91 | 1.00 | 1.00 | |||||
| Yes | 135 | 2.51 | (2.04, 3.08) | 2.19 | (1.78–2.70) | 6 | 3.97 | (1.71–9.21) | 2.98 | (1.25–7.10) | |
| P-value | <0.001 | <0.001 | 0.001 | 0.014 | 0.336 | ||||||
Abbreviations: ca, cases; RR, relative risks; CI, confidence intervals.
a
Model adjusted for age, study site, race/ethnic groups, part-white status, sex, and education.
b
Additionally adjusted for ever-sunburned status, family history of melanoma, personal history of non-melanoma skin cancer.
c
Tests heterogeneity between whites and non-whites/multiracials.
d
Also adjusted for sunburn susceptibility phenotype index.
e
One melanoma in situ case with missing information regarding lifetime number of sunburns and age of first sunburn.