Background
Methods
Study design and data collection
Data collection
Inclusion criteria and exclusion criteria
Determinants of ASP
Statistical analysis
Results
Study population
Namibia Non-Black (N = 97) | Namibia Black (N = 380) | Uganda (N = 418) | Nigeria (N = 383) | Zambia (N = 198) | Overall (N = 1476) | |
---|---|---|---|---|---|---|
N (%) | N (%) | N (%) | N (%) | N (%) | N (%) | |
Mean age at diagnosis, years (SD) | 56.7 (12.5) | 52.6 (15.0) | 48.4 (12.7) | 48.7 (12.3) | 50.0 (14.8) | 50.3 (13.7) |
BMI, kg/m2 | ||||||
< 25 | 31 (32.0) | 162 (42.6) | 201 (48.1) | 162 (42.3) | 81 (40.9) | 637 (43.2) |
[25–30[ | 20 (20.6) | 98 (25.8) | 148 (35.4) | 107 (27.9) | 53 (26.8) | 426 (28.9) |
30 + | 41 (42.3) | 102 (26.8) | 60 (14.4) | 94 (24.5) | 45 (22.7) | 342 (23.2) |
Unknown | 5 (5.2) | 18 (4.7) | 9 (2.2) | 20 (5.2) | 19 (9.6) | 71 (4.8) |
Education | ||||||
None/primary | 13 (13.4) | 197 (51.8) | 242 (57.9) | 102 (26.6) | 103 (52.0) | 657 (44.5) |
Secondary/high school | 46 (47.4) | 132 (34.7) | 126 (30.1) | 144 (37.6) | 54 (27.3) | 502 (34.0) |
Technical/university | 38 (39.2) | 51 (13.4) | 50 (12.0) | 137 (35.8) | 41 (20.7) | 317 (21.5) |
HIV status | ||||||
Positive | 3 (3.1) | 53 (13.9) | 48 (11.5) | 9 (2.3) | 31 (15.7) | 144 (9.8) |
Hypertension | ||||||
Yes | 49 (50.5) | 155 (40.8) | 65 (15.6) | 100 (26.1) | 57 (28.8) | 426 (28.9) |
Tumour stage at diagnosis | ||||||
Localized (stage TNM I/II) | 48 (49.5) | 73 (19.2) | 96 (23.0) | 39 (10.2) | 19 (9.6) | 275 (18.6) |
Locally advanced (stage TNM III) | 43 (44.3) | 247 (65.0) | 226 (54.1) | 256 (66.8) | 131 (66.2) | 903 (61.2) |
Metastatic (stage TNM IV) | 6 (6.2) | 60 (15.8) | 64 (15.3) | 60 (15.7) | 13 (6.6) | 203 (13.8) |
Unknown | 0 (0.0) | 0 (0.0) | 32 (7.7) | 28 (7.3) | 35 (17.7) | 95 (6.4) |
Treated | ||||||
No | 0 (0.0) | 1 (0.3) | 36 (8.6) | 95 (24.8) | 39 (19.7) | 171 (11.6) |
Yes | 97 (100.0) | 376 (98.9) | 359 (85.9) | 262 (68.4) | 140 (70.7) | 1234 (83.6) |
Unknown | 0 (0.0) | 3 (0.8) | 23 (5.5) | 26 (6.8) | 19 (9.6) | 71 (4.8) |
Surgerya | ||||||
No | 9 (9.3) | 88 (23.2) | 125 (29.9) | 150 (39.2) | 85 (42.9) | 457 (31.0) |
Yes | 84 (86.6) | 244 (64.2) | 240 (57.4) | 183 (47.8) | 90 (45.5) | 841 (57.0) |
Unknown | 4 (4.1) | 48 (12.6) | 53 (12.7) | 50 (13.1) | 23 (11.6) | 178 (12.1) |
Radiotherapy | ||||||
No | 24 (24.7) | 72 (18.9) | 276 (66.0) | 308 (80.4) | 130 (65.7) | 810 (54.9) |
Yes | 71 (73.2) | 287 (75.5) | 56 (13.4) | 11 (2.9) | 40 (20.2) | 465 (31.5) |
Unknown | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
Endocrine therapy | ||||||
No | 18 (18.6) | 76 (20.0) | 194 (46.4) | 210 (54.8) | 109 (55.1) | 607 (41.1) |
Yes | 76 (78.4) | 276 (72.6) | 151 (36.1) | 127 (33.2) | 64 (32.3) | 694 (47.0) |
Unknown | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
Chemotherapy | ||||||
No | 26 (26.8) | 64 (16.8) | 74 (17.7) | 164 (42.8) | 55 (27.8) | 383 (25.9) |
Yes | 70 (72.2) | 290 (76.3) | 283 (67.7) | 170 (44.4) | 115 (58.1) | 928 (62.9) |
Unknown | 1 (1.0) | 26 (6.8) | 61 (14.6) | 49 (12.8) | 28 (14.1) | 165 (11.2) |
Distribution of self-reported ASP
Cumulative incidence of self-reported ASP
No. women with outcome/total (competing deaths) | Time at risk (person-years) | ASP type-specific cumulative incidence at 4 years since diagnosis (95% CI) | |
---|---|---|---|
Shoulder/arm pain | |||
All sites/ethnicities | 618/1476 (449) | 680 | 43.0 (40.4–45.6) |
Namibia non-black | 25/97 (12) | 42 | 26.0 (17.7–35.1) |
Namibia black | 151/380 (100) | 218 | 40.3 (35.3–45.2) |
Uganda | 214/418 (119) | 174 | 51.8 (46.9–56.5) |
Nigeria | 162/383 (141) | 168 | 44.0 (38.7–49.3) |
Zambia | 66/198 (77) | 77 | 35.1 (28.3–42.0) |
Arm stiffness | |||
All sites/ethnicities | 516/1476 (505) | 628 | 35.8 (33.4–38.3) |
Namibia non-black | 26/97 (13) | 34 | 26.9 (18.5–36.0) |
Namibia black | 148/380 (106) | 209 | 39.3 (34.3–44.2) |
Uganda | 184/418 (133) | 201 | 44.7 (39.8–49.5) |
Nigeria | 106/383 (176) | 124 | 28.8 (24.2–33.6) |
Zambia | 52/198 (77) | 60 | 27.9 (21.6–34.5) |
Arm/hand swelling | |||
All sites/ethnicities | 319/1476 (602) | 464 | 22.5 (20.4–24.8) |
Namibia non-black | 13/97 (16) | 29 | 13.7 (7.7–21.4) |
Namibia black | 81/380 (130) | 144 | 21.9 (17.8–26.3) |
Uganda | 103/418 (180) | 122 | 25.1 (21.0–29.4) |
Nigeria | 84/383 (191) | 120 | 23.3 (19.0–28.0) |
Zambia | 38/198 (85) | 50 | 20.4 (15.0–26.5) |
Determinants of first self-reported ASP
No. women with outcome/total | Fully adjusted CHR (95%CI)a,b | ||||||||
---|---|---|---|---|---|---|---|---|---|
Shoulder/arm pain | Arm stiffness | Arm/hand swelling | Shoulder/arm pain | Arm stiffness | Arm/hand swelling | ||||
Study site, ethnicity | |||||||||
Namibia Black | 151/380 | 148/380 | 81/380 | 1 | 1 | 1 | 0.001 | ||
Namibia Non-Black | 25/97 | 26/97 | 13/97 | 0.71 (0.46–1.10) | < 0.0001 | 0.78 (0.50–1.20) | 0.0002 | 0.68 (0.37–1.24) | |
Uganda | 214/418 | 184/418 | 103/418 | 2.00 (1.61–2.48) | 1.52 (1.21–1.90) | 1.59 (1.18–2.15) | |||
Nigeria | 162/383 | 106/383 | 84/383 | 1.88 (1.48–2.39) | 1.06 (0.81–1.39) | 1.69 (1.21–2.34) | |||
Zambia | 66/198 | 52/198 | 38/198 | 1.19 (0.88–1.61) | 0.91 (0.66–1.27) | 1.35 (0.90–2.03) | |||
Age at diagnosis (years) | |||||||||
< 50 | 307/780 | 255/780 | 157/780 | 1 | 0.06 | 1 | 0.23 | 1 | 0.10 |
≥ 50 | 311/696 | 261/696 | 162/696 | 1.18 (0.99–1.39) | 1.12 (0.93–1.35) | 1.22 (0.96–1.53) | |||
per 10 years increase | 618/1476 | 516/1476 | 319/1476 | 1.04 (0.98–1.11) | 0.21 | 1.04 (0.97–1.11) | 0.31 | 1.04 (0.95–1.13) | 0.43 |
BMI (Kg/m2) | |||||||||
< 25 | 273/637 | 229/637 | 129/637 | 1 | 0.37 | 1 | 0.30 | 1 | 0.41 |
[25–30[ | 176/426 | 144/426 | 95/426 | 0.88 (0.72–1.06) | 0.89 (0.72–1.09) | 1.04 (0.79–1.35) | |||
30 + | 140/342 | 120/342 | 80/342 | 0.99 (0.80–1.21) | 1.07 (0.85–1.34) | 1.21 (0.91–1.60) | |||
per 5 kg/m2 increase | 618/1476 | 516/1476 | 319/1476 | 1.00 (0.93–1.07) | 0.94 | 1.03 (0.96–1.12) | 0.40 | 1.11 (1.01–1.22) | 0.03 |
Education | |||||||||
University/technical | 106/317 | 84/317 | 66/317 | 1 | 1 | 1 | 0.07 | ||
Secondary/high school | 196/502 | 161/502 | 95/502 | 1.48 (1.16–1.88) | 1.41 (1.08–1.84) | 1.08 (0.78–1.49) | |||
None/Primary school | 316/657 | 271/657 | 158/657 | 1.94 (1.51–2.49) | 1.77 (1.34–2.33) | 1.41 (1.02–1.96) | |||
Per decrease in educational level | 618/1476 | 516/1476 | 319/1476 | 1.38 (1.22–1.56) | < 0.0001 | 1.32 (1.16–1.51) | < 0.0001 | 1.20 (1.02–1.41) | 0.03 |
HIV status at breast cancer diagnosis | |||||||||
Negative/Unknown | 562/1332 | 460/1332 | 291/1332 | 1 | 0.85 | 1 | 0.14 | 1 | > 0.99 |
Positive | 56/144 | 56/144 | 28/144 | 0.97 (0.73–1.29) | 1.24 (0.93–1.65) | 1.00 (0.67–1.49) | |||
Ever diagnosed with hypertension | |||||||||
No | 432/1050 | 363/1050 | 215/1050 | 1 | 0.11 | 1 | 0.99 | 1 | 0.15 |
Yes | 186/426 | 153/426 | 104/426 | 1.17 (0.96–1.42) | 1.00 (0.81–1.23) | 1.22 (0.93–1.58) | |||
Tumour stage at diagnosis | |||||||||
Localized | 91/275 | 79/275 | 40/275 | 1 | < 0.0001 | 1 | < 0.0001 | 1 | < 0.0001 |
Locally advanced | 413/903 | 343/903 | 207/903 | 1.70 (1.35–2.14) | 1.66 (1.29–2.13) | 1.98 (1.40–2.79) | |||
Metastatic | 79/203 | 68/203 | 48/203 | 2.44 (1.78–3.33) | 2.69 (1.92–3.77) | 4.02 (2.59–6.23) | |||
Prior treatment | |||||||||
No | 105/237 | 75/221 | 41/197 | 1 | 0.01 | 1 | 0.08 | 1 | 0.01 |
Yes | 496/1168 | 429/1184 | 270/1208 | 1.37 (1.08–1.72) | 1.27 (0.97–1.67) | 1.67 (1.16–2.41) | |||
Prior surgeryc | |||||||||
No | 248/512 | 185/497 | 116/482 | 1 | 0.01 | 1 | 0.21 | 1 | 0.19 |
Yes | 309/786 | 280/801 | 173/816 | 0.76 (0.63–0.92) | 0.87 (0.70–1.08) | 0.83 (0.63–1.09) | |||
Prior radiotherapy | |||||||||
No | 397/854 | 316/850 | 186/825 | 1 | 0.60 | 1 | 0.22 | 1 | 0.59 |
Yes | 147/421 | 135/425 | 86/450 | 1.07 (0.83–1.38) | 0.85 (0.65–1.10) | 1.10 (0.77–1.59) | |||
Prior chemotherapy | |||||||||
No | 184/438 | 133/418 | 79/400 | 1 | 0.0002 | 1 | 0.001 | 1 | 0.001 |
Yes | 370/873 | 327/893 | 206/911 | 1.48 (1.21–1.82) | 1.48 (1.17–1.87) | 1.65 (1.22–2.23) | |||
Prior endocrine therapy | |||||||||
No | 328/703 | 247/672 | 151/649 | 1 | 0.59 | 1 | 0.87 | 1 | 0.45 |
Yes | 234/598 | 218/629 | 132/652 | 1.06 (0.86–1.29) | 0.98 (0.79–1.22) | 0.90 (0.68–1.18) | |||
Sensitivity analysis conditioned on 6 months survival and excluding metastatic women | |||||||||
Prior treatment | |||||||||
Yes vs. No | 419/1037 | 366/1039 | 214/1045 | 1.58 (1.14–2.18) | 0.01 | 1.37 (0.95–1.98) | 0.10 | 1.39 (0.86–2.24) | 0.18 |
Prior surgery | |||||||||
Yes vs. No | 280/769 | 254/771 | 149/776 | 0.77 (0.62–0.95) | 0.02 | 0.92 (0.73–1.17) | 0.50 | 0.84 (0.62–1.14) | 0.26 |
Prior radiotherapy | |||||||||
Yes vs. No | 125/382 | 116/380 | 76/401 | 0.83 (0.64–1.09) | 0.18 | 0.70 (0.53–0.92) | 0.01 | 0.91 (0.62–1.32) | 0.61 |
Prior chemotherapy | |||||||||
Yes vs. No | 339/813 | 300/813 | 178/821 | 1.67 (1.31–2.12) | < 0.0001 | 1.52 (1.17–1.97) | 0.002 | 1.59 (1.12–2.25) | 0.01 |
Prior endocrine therapy | |||||||||
Yes vs. No | 218/576 | 200/582 | 118/597 | 0.97 (0.79–1.19) | 0.74 | 0.99 (0.80–1.23) | 0.93 | 0.87 (0.65–1.15) | 0.32 |