Indicators of risk for breast cancer in Malta: a case-control study among Maltese female patients and age-matched hospital controls

Abstract

Breast cancer accounts for a significant amount of the total morbidity and mortality in Maltese women. It caused 31 % of all cancer deaths in Maltese females of all ages in 1995. The aim of this study was to evaluate the relevance of risk factors documented in the international medical literature to the Maltese female population and to estimate differences in these risk indicators between the breast cancer population and age-matched hospital controls. Selected factors included age, social class and educational attainment, locality of residence, menstrual and reproductive factors, family history, smoking and alcohol consumption, diabetes mellitus, past history of other breast disease, body weight, and measures of height, waist and hip circumference. The cases were identified from registrations for invasive breast cancer in the Malta National Cancer Registry for the period 1994-1995, who were residents in Malta. Half of these cases were approached and interviewed with a set questionnaire featuring all the above-mentioned indicators. The controls were interviewed using the same questionnaire and they were selected from women who were admitted to St Luke's Hospital, with no past or present history of a malignancy. Statistical significance was reached for age at menopause, age at first full-term pregnancy, family history, past history of other breast disease and body mass index. The study shows that several of the risk factors demonstrated elsewhere in the world are relevant for the Maltese population.