A Cluster Analysis of Substance Use, Anthropometric and Reproductive Health Profiles among Alcohol- and/or Tobacco-Using Women with Breast Cancer in Southeastern Nigeria: Implications for Risk Assessment

Abstract

Background: Breast cancer remains a major public health challenge in sub-Saharan Africa and Nigeria, where late presentation, limited diagnostic access and health-system constraints continue to worsen outcomes. Alcohol use, cigarette smoking, adiposity and reproductive history are recognised risk domains, but their combined profiles among Nigerian women with breast cancer are not well described. This study explored whether alcohol- and/or tobacco-using women with breast cancer in Southeastern Nigeria could be grouped into clinically meaningful phenotypic clusters. Methodology: This hospital-based cross-sectional analytical study included 139 women with histologically confirmed breast cancer who reported alcohol use and/or cigarette smoking. Data were collected using an interviewer-administered questionnaire and direct anthropometric measurements. Variables included substance-use pattern, body mass index, waist-to-hip ratio, menopausal status, parity and age at menarche. An exploratory hierarchical cluster analysis using Ward’s method was performed, followed by bivariate profiling of the derived clusters. Results: The mean age of participants was 37.3 ± 9.6 years, and 76.2% were younger than 50 years. Most participants were premenopausal (79.9%). Alcohol-only use was the commonest substance-use category (70.5%), followed by tobacco-only use (15.8%) and dual alcohol-tobacco use (13.7%). The analysis identified two clusters. Cluster 1 (n = 108; 77.7%) was characterised by younger age, premenopausal status and lower parity. Cluster 2 (n = 31; 22.3%) was characterised by older age, predominantly postmenopausal status and higher parity. Substance-use pattern, body mass index and waist-to-hip ratio did not significantly differentiate the clusters. Conclusion: Among alcohol- and/or tobacco-using women with breast cancer in this Southeastern Nigerian hospital sample, reproductive life stage, age and parity distinguished two phenotypic clusters more clearly than substance-use pattern or anthropometric measures. These findings should be interpreted cautiously because of the cross-sectional design, hospital-based sampling and limited tumour biology data. The results support further prospective studies that combine behavioural, reproductive, anthropometric and tumour molecular variables for more refined breast-cancer risk profiling in Nigeria.