Clustering 46 Asian Countries According to the Trend of Breast Cancer Incidence Rate from 1990-2016: An Application of Growth Mixture Model

Breast cancer is the second cause of death in Asian countries, and 39% of all new breast cancer cases are diagnosed in Asia. The current study was designed to identify different patterns of breast cancer incidence rates among Asian countries. In this secondary analysis study, information about the incidence rates of female breast cancer for 46 Asian countries was extracted from the Gapminder website from 1990 to 2016, and a growth mixture model was developed to describe the growth patterns and identify the main longitudinal trends in Mplus 7.4. Finally, the estimated trend in each cluster was characterized by intercept (the rate at 1990) and slope (the observed annual trend changes). Our findings suggested an overall increasing trend throughout the continent, but individual trajectories showed different behavior patterns amongst countries. Bayesian information creation showed that the 3-cluster model was the best choice. The annual growth of -0.13 (per 100,000 persons) suggests a slight negative trend for the incidence rate of breast cancer in cluster one countries, including Bangladesh, Israel, Kyrgyz Republic, Maldives, Nepal, North Korea, Tajikistan, and Timor- Leste. Seventeen countries, including Armenia, Bahrain, Brunei, Cyprus, Iraq, Japan, Jordan, Kazakhstan, Kuwait, Lebanon, Malaysia, Pakistan, Philippines, Qatar, Singapore, South Korea, and United Arab Emirates, which belonged to cluster 2 had not only a higher number of incidence rate in 1990, but also an annual growth of 0.96 (per 100,000 persons), indicating a sharp increase trajectory. Also, annual growth of 0.38 (per 100,000 persons) showed a slow increase in the incidence rate of breast cancer over time for the 21 remaining countries. The observed sharp increase of breast cancer incidence in Armenia, Bahrain, Brunei, Cyprus, Iraq, Japan, Jordan, Kazakhstan, Kuwait, Lebanon, Malaysia, Pakistan, Philippines, Qatar, Singapore, South Korea, and United Arab Emirates is remarkable; therefore, effective strategies to prevent it are urgently required.