Modeling the Trend Changes of Liver Cancer Mortality in the 6 WHO Regions.

BACKGROUND: There is little information about comparison of the mortality patterns in different regions. The current study aimed to assess the trend changes of liver cancer mortality in 6 WHO regions. METHODS: The mortality rates of liver cancer in the 6 WHO regions during 1990 to 2017 were extracted from the Global Burden of Disease database. Growth mixture model was used to identify the latent patterns using a set of tools to handle both the within and between trajectory variations. All the modeling procedures were implemented in Mplus 7.4 software. RESULTS: The mortality rate in Africa showed a slow decreasing trend throughout the observation period, but a slow increase was observed in the Eastern Mediterranean region, European region, region of the Americas, and South-East Asia region. The slope of the rise in liver cancer mortality rate for Western Pacific region was 3-4 times higher than the other regions. 2-pattern growth mixture model was estimated as the best model. The Western Pacific region with annual increase of 0.20 in the liver cancer mortality rate was in the first pattern and the other 5 regions including Africa region, Eastern Mediterranean region, European region, region of the Americas, and South-East Asia region with annual increase of 0.05 in liver cancer mortality rate belonged to the second pattern. CONCLUSION: Observed pattern in the Western Pacific region is not favorable. Taking into account a set of urgent prevention actions to control mortality rate of liver cancer in this region seems necessary.

Clustering time trends of breast cancer incidence in Africa: a 27-year longitudinal study in 53 countries.

BACKGROUND: Breast cancer is the most common, frequently diagnosed cancer with the highest incidence among female worldwide. Although the incidence is decreasing in developed countries, it is on increase in most of the African countries. OBJECTIVE: This study aimed to identify different time trends of breast cancer incidence among African countries using latent mixture approach. METHODS: The information includes newly diagnosed breast cancer patients per 100,000 women for 53 African countries in a period of 1990-2016. Latent mixture modeling was performed in Mplus 7.4 software. RESULTS: The overall trend of breast cancer in Africa was increasing. Latent mixture model with 5 clusters was estimated as the best using fit indices and linear growth trajectories were specified for each cluster. Nigeria was the only country which belongs to a cluster with negative slope indicating a slow decrease in the breast cancer incidence; also, Seychelles was the only country that showed a sharp increase over time. 31 countries belonged to a cluster with a slope of 0.08, indicating that the incidence of breast cancer is almost constant over time. Cluster 3 including Algeria, Angola, Botswana, Central African Republic, Cote d'lvoire, Equatorial Guinea, Lesotho, Libya, Namibia, Somalia, Sudan, Swaziland, Uganda and Zimbabwe and cluster 2 including Gabon, Mauritius, Morocco, South Africa, Tunisia and Congo showed a slow and moderate increase in the incidence of breast cancer, respectively. CONCLUSION: Providing health education programs is essential in African countries with rising trend of breast cancer during the last decades.

Clustering Trend Changes of Lung Cancer Incidence in Europe via the Growth Mixture Model during 1990-2016.

Background: Lung cancer accounts for half of all deaths from cancer in Europe and has the highest incidence in Southern Europe. The current study aimed to cluster trend changes of lung cancer incidence in Europe via the growth mixture model. Methods: The dataset included incidence rates of female and male lung cancer per 100,000 for 42 European countries during 1990-2016 compiled from the Gapminder database. The growth mixture model was implemented to recognize different longitudinal patterns and estimate the linear trend of each pattern in Mplus 7.4 software. Results: The observed overall trend of incidence for female and male lung cancer was raising and falling, respectively, and Iceland was the only country with higher incidence of female versus male lung cancer in 2016. The growth mixture model suggests 3 main patterns for the trend of lung cancer incidence both for males and females. In male lung cancer, a sharp decreasing pattern was detected for 6 countries including Belarus, Estonia, Russia, Slovenia, Ukraine, and the United Kingdom; also, a moderately decreasing pattern was observed among the other countries. In female lung cancer, a moderate increasing trend was observed for 8 countries including the United Kingdom, Denmark, Hungary, Iceland, Ireland, Montenegro, Netherlands, and Norway; the other patterns were categorized into two clusters with slow increasing trends. Conclusion: Given the raising patterns in the incidence of lung cancer among European females, especially in the United Kingdom, Denmark, Hungary, Iceland, Ireland, Montenegro, Netherlands, and Norway, urgent effective measures are recommended to be taken.

Trends and Risk Factors of Gastric Cancer in Iran (2005-2010).

BACKGROUND: Gastric cancer (GC) is the first and the third prevalent cancer among males and females in Iran, respectively. The aim of this study was mainly to identify high-risk areas of GC by assessing the spatial and temporal pattern of incidence, and second, to explore some risk factors of GC in ecological setting. METHODS: In this cross-sectional ecological study we used Bayesian hierarchical space-time model to measure the relative risk and temporal trends of GC in Iran from 2005 to 2010 based on available data. Data analysis was done by the use of integrated nested Laplace approximation Bayesian approach in R software. RESULTS: Overall trend of GC was significantly decreasing during the study period. Ardabil, Khorasan Razavi, West Azarbaijan, Zanjan, and Mazandaran provinces had the highest risk of incidence. Overweight and smoking were directly and significantly associated with GC risk. CONCLUSIONS: During the study period, GC has decreased in Iran. Nevertheless, GC risk was generally high in Northern and Northwestern provinces of Iran. Different health policies according to GC risk and trend are required for each province. Improvements in screening and education programs and conducting further epidemiological studies could help to reduce the incidence of GC in high risk provinces.

Burden of Oral Diseases in Iran, 1990-2010: Findings from the Global Burden of Disease Study 2010.

BACKGROUND: Oral diseases, as a group of chronic diseases, are among the major public health problems that lead to disability throughout the world. The major part of burden of oral diseases is caused by dental caries, periodontal diseases, edentulism, mouth cancer, cleft lip, and cleft palate. The aim of the present paper is to report the global results for the burden of oral disease in Iran from 1990 to 2010, derived from GBD study 2010 by sex and age. METHODS: The Global Burden of Disease Study 2010 (GBD 2010) was a systematic effort with a common framework to estimate disability adjusted life years (DALYs) for diseases in different parts of the world. Years of life lost due to premature mortality (YLLs) were assessed based on cause-of-death estimates and by means of a cause of death ensemble model (CODEm). Years of life lost due to disability (YLDs) were computed by multiplying the prevalence, the disability weight for a sequel, and the duration of symptoms. A systematic review of published and unpublished data was conducted to estimate disease distribution using a Bayesian meta-regression method (DisMod-MR). Disability weights were measured by collecting data from population-based surveys. In this paper, we describe the results of GBD 2010 regarding oral diseases in Iran, critique the results, and provide some recommendations. RESULTS: Between 1990 and 2010 in Iran, an increase occurred in DALYs at all ages, attributed to dental caries (from 37,230 to 56,521) as well as periodontal diseases (from 21,482 to 43,308), and a decrease was found for edentulism (from 53,134 to 47,960). DALYs at all ages attributed to mouth cancer increased (from 5,597 to 7,771), while a decline was noted for cleft lip and cleft palate (from 6,157 to 5,034). The age-standardized DALY rates per 100,000 population did not considerably change for dental caries and periodontal diseases, while edentulism showed a reduction. The corresponding DALY rate due to mouth cancer decreased, while it remained almost unchanged for cleft lip and cleft palate over this period. DALY rates per 100,000 population due to dental caries and edentulism were higher among Iranian women than for Iranian men at all ages, while Iranian men suffered from a higher burden of periodontal disease, mouth cancer, cleft lip, and cleft palate. The most significant burden due to dental caries and periodontal diseases was found in Iranians aged 15-49 and 50-69 years, respectively and edentulism and mouth cancer led to the highest burden in Iranians older than 70 years of age. The highest burden caused by cleft lip and cleft palate occurred in children younger than 5 years old. CONCLUSION: The findings address the challenging changes in oral diseases and difficulties in responding to the urgent oral health needs in Iran. The burden of oral diseases should be considered as a priority in Iran. A need also exists to pay more attention to the oral health policies and principles of preventive oral care. Global analyses of disease burdens provide a useful framework to guide a suitable policy in response to disease changes. In fact, strong national and sub-national analyses will be required to provide more effective public health strategies.