Article: Risk factors for cervical cancer in Mozambican women
Cervical cancer is the most prevalent cancer and the leading cause of death from cancers among women in sub-Saharan Africa [1].
Berit Rostad, Berit Schei, F. da Costa (28.04.2004)
The etiology of cancer of the cervix has been described in many populations of the world, but very few researchers have targeted sub-Saharan African populations [2].
The principal objective of the present study was to identify risk factors for the development of cervical cancer in women in Mozambique. The hospital-based case-control study of 113 women with invasive cervical cancer and 120 control women free of any cervical malignancy, enabled evaluation of risk factors. Data were collected by structured interviews with the patients. The sociodemographic characteristics of cases and controls are presented in Table 1.
Between-group comparisons showed marked differences in sexual behavior and reproductive history. The control for age did not modify the differences (Table 2).
The significant differences are analyzed in more detail in Table 3. Sexually transmitted diseases were considered to be linked to cervical cancer risk through the correlation with sexual partners. The cases were more likely to have a high risk profile than the controls, as to early sexual debut, more sexual partners, more deliveries and lower educational attainment, indicating socioeconomic status.
The results presented in Table 3 add evidence to the hypothesis that cancer of the cervix is more prevalent in lower socioeconomic groups [3]. The association persisted when controlled for number of sexual partners and age of sexual debut. The results of the present study emphasized the importance of sexual activity. The association with multiple sexual partners is most likely explained by the elevated risk of contracting an infectious agent, playing a causal role for the development of cervical neoplasia. Early age at first coitus may strengthen this association as the immature cervical epithelium represents an increased susceptibility and vulnerability to oncogenic agents and to sexually transmitted diseases. The risk associated with multiple sexual partners might also depend on the male partners' sexual health, but we were not in a position to evaluate the sexual behavior of the women's partners.
Sociodemographic characteristics of cases and controls
Table 1
|
Characteristics
|
Cases (n=113)
No. (%)
|
Controls (n= 120)
No. (%)
|
|
Age
|
|
|
|
25-34
|
28 (25%)
|
81 (67%)
|
|
35-44
|
41 (36%)
|
37 (31%)
|
|
45-59
|
44 (39%)
|
2 (2%)
|
|
Civil status
|
|
|
|
Married/living with family
|
92 (81%)
|
94 (78%)
|
|
Single
|
21 (19%)
|
26 (22%)
|
|
Education
|
|
|
|
≥10 years
|
5 (4%)
|
21 (17%)
|
|
1-9 years
|
74 (66%)
|
91 (76%)
|
|
Illiterate
|
34 (30%)
|
8 (7%)
|
|
Attended health education
|
35 (31%)
|
64 (53%)
|
|
Family planning classes
|
4 (4%)
|
27 (23%)
|
|
Pregnancy/child care
|
14 (12%)
|
34 (28%)
|
|
Hygiene/nutrition
|
22 (19%)
|
28 (23%)
|
|
Employment
|
|
|
|
Housewife
|
76 (67%)
|
84 (70%)
|
|
Paid employment
|
37 (33%)
|
36 (30%)
|
Several studies have documented a pronounced association between number of births and cervical neoplasia [4]. Analyses in Table 3 supported this assumption, multiparity remained a significant predictor of risk as the risk increased with increasing number of births. The apparent inverse correlation between low socioeconomic status and cervical cancer may be partially determined by multiparity as the illiterate women had on average more deliveries.
Reproductive health, sexual and contraceptive behavior in cases and controls
Table 2
|
Characteristics
|
Cases (n=113)
No. (%)
|
Controls (n=120)
No. (%)
|
P
|
|
Parity
|
|
|
0.00
|
|
Nullipara
|
10 (9%)
|
11 (9%)
|
|
|
1-5
|
51 (45%)
|
86 (72%)
|
|
|
6-10
|
47 (42%)
|
22 (18%)
|
|
|
≥11
|
5 (4%)
|
1 (1%)
|
|
|
Age at first deliveryª
|
|
|
0.00
|
|
≤15
|
16 (14%)
|
14 (12%)
|
|
|
16-19
|
54 (48%)
|
34 (28%)
|
|
|
≥20
|
33 (29%)
|
56 (47%)
|
|
|
Infertility diagnosed/suspected
|
31 (27%)
|
22 (18%)
|
0.08
|
|
Sexually transmitted diseases
|
58 (51%)
|
13 (11%)
|
0.00
|
|
Contraceptive practices
|
35 (31%)
|
66 (55%)
|
0.00
|
|
Age sexual debutª
|
|
|
0.00
|
|
≤15
|
53 (47%)
|
23 (19%)
|
|
|
16-19
|
49 (43%)
|
58 (48%)
|
|
|
≥20
|
11 (10%)
|
23 (19%)
|
|
|
Number of sexual partnersª
|
|
|
0.00
|
|
1-5
|
89 (79%)
|
115 (96%)
|
|
|
≥6
|
22 (19%)
|
5 (4%)
|
ªUnknowns are eliminated from analyses.
Risk of cervical cancer in relation to selected sociodemographic, reproductive and sexual behavior characteristics
Table 3
| |
Cases (n=113) No.
|
Controls (n=120) No.
|
Odds ratio
|
95% confidence interval
|
|
Woman's years of education
|
|
|
|
|
|
≥10
|
5
|
21
|
1.0
|
|
|
1-9
|
74
|
91
|
3.4
|
1.23-9.40
|
|
Illiterate
|
34
|
8
|
17.8
|
5.15-61.43
|
|
Age sexual debutª
|
|
|
|
|
|
≥20
|
11
|
23
|
1.0
|
|
|
16-19
|
49
|
58
|
1.8
|
0.80-4.03
|
|
15
|
53
|
23
|
4.8
|
2.03-11.35
|
|
Number of births
|
|
|
|
|
|
0-l
|
14
|
29
|
1.0
|
|
|
2-4
|
35
|
58
|
1.3
|
0.61-2.77
|
|
≥5
|
64
|
33
|
4.0
|
2.03-5.44
|
|
Number of sexual partnersª
|
|
|
|
|
|
1-5
|
89
|
115
|
1.0
|
|
|
>6
|
22
|
5
|
5.7
|
2.08-15.56
|
ªUnknowns are eliminated from analyses.
Differentials in reproductive history, sexual behavior and low socioeconomic status can explain the variations in cervical cancer prevalence.
Originally published in International Journal of Gynecology and Obstetrics 80 (2003) 63-65
Ó 2002 International Federation of Gynecology and Obstetrics. Published by Elsevier Science Ireland Ltd. All rights reserved.
References
[1] The World Bank Investing in health. World Development Report, 1993. Washington, DC: World Bank, 1994.
[2] Williams MA, Kenya PR, Mati JKG, Thomas DB. Risk factors for invasive cervical cancer in Kenyan women. Int J Epidemiol 1994;23:906-912.
[3] dos-Santos IS, Beral V. Socio-economic differences in reproductive behaviour. IARC Sei Publ 1997;138:285-308.
[4] Kjaer SK, Dahl C, Engholm G, Bock JE, Lynge E, Jensen OM. Case-control study of risk factors for cervical neoplasia in Denmark. Cancer Causes and Control 1992;3:339-348.
© 2004 North South. Gendered Views from Norway. Special edition of Kvinneforskning (Journal of Gender Research in Norway). Article published April 28, 2004