Bayesian spatial-temporal analysis and determinants of cardiovascular diseases in Tanzania mainland.

BACKGROUND: Cardiovascular Diseases (CVDs) are health-threatening conditions that account for high mortality in the world. Approximately 23.6 million deaths due to CVD is expected in the year 2030 worldwide. The CVD burden is more severe in developing countries, including Tanzania. OBJECTIVES: This study analyzed the spatial-temporal trends and determinants of cardiovascular diseases in Tanzania from 2010 to 2019. METHODS: Individual data were extracted from Jakaya Kikwete Cardiac Institute (JKCI), Mbeya Zonal Referral Hospital (MZRH), Kilimanjaro Christian Medical Centre (KCMC) and Bugando hospitals and the geographical data from TMA. The model containing spatial and temporal components was analyzed using the Bayesian hierarchical method implemented using Integrated Nested Laplace Approximation (INLA). RESULTS: The results found that the incidence of CVD increased from 2010 to 2014 and decreased from 2015 to 2019. The southern highlands, lake, central and coastal zones were more likely to have CVD problems than others. It was also revealed that people aged 60-64 years OR = 1.49, females OR = 1.51, smokers OR = 1.76, alcohol drinkers OR = 1.48, and overweight OR = 1.89 were more likely to have CVD problems. Additionally, a 1oC increase in the average annual air maximum temperature was related to a 14% risk of developing CVD problems. The study revealed that the model, which included spatial and temporal random effects, was the best-predicting model. CONCLUSION: The study shows a decreased CVD incidence rate from 2015 to 2019. The CVD incidences occurred more in Tanzania's coastal and lake areas between 2010 and 2019. The demographic, lifestyle and geographical risk factors were significantly associated with the CVD.

The distribution of cardiovascular diseases in Tanzania: a spatio-temporal investigation.

Cardiovascular Disease (CVD) is currently the major challenge to people's health and the world's top cause of death. In Tanzania, deaths due to CVD account for about 13% of the total deaths caused by the non-communicable diseases. This study examined the spatio-temporal clustering of CVDs from 2010 to 2019 in Tanzania for retrospective spatio-temporal analysis using the Bernoulli probability model on data sampled from four selected hospitals. Spatial scan statistics was performed to identify CVD clusters and the effect of covariates on the CVD incidences was examined using multiple logistic regression. It was found that there was a comparatively high risk of CVD during 2011-2015 followed by a decline during 2015-2019. The spatio-temporal analysis detected two high-risk disease clusters in the coastal and lake zones from 2012 to 2016 (p<0.001), with similar results produced by purely spatial analysis. The multiple logistic model showed that sex, age, blood pressure, body mass index (BMI), alcohol intake and smoking were significant predictors of CVD incidence.

Provision of sexual health education in secondary schools: A multidisciplinary lens of stakeholders in southern highlands, Tanzania.

Introduction: School-based sexual health education reduces risky sexual outcomes for in-school adolescents such as unintended premarital pregnancies, unsafe abortions, increased risk of contracting sexually transmitted infections (STIs) including HIV and AIDS, early parenthood, a massive dropout from schools and untimely deaths. Despite the teaching of sexual health education in secondary schools, adolescents in Iringa Region are being exposed to increasing risks of sexual behaviours such as premarital sex, multiple sexual partners, and unprotected sex. This study examines stakeholders' attitudes and beliefs toward providing sexual health education in secondary schools in Iringa Region, Tanzania. Methods: A qualitative approach under cross-sectional design was used. A purposive sampling technique was applied in selecting the Districts and participants for the study while simple random was used in the selection of schools. The participants were purposively selected depending on their position and knowledge of the subject matter. This study had 50 participants in total, 36 of them were teachers (6 from each school) who participated in focus group discussions (FGDs). After that, in-depth interviews with 14 participants were also conducted including 6 headmasters/mistresses, 6 healthcare professionals and 2 District secondary education officers. All FGDs and in-depth interviews used standardized questions to elicit information. The collected data were audio-recorded through tape recorders, transcribed, and translated into English. An initial coding matrix was developed and refined throughout the coding process. Transcripts were coded and analyzed using the content analysis approach. Results: Findings from this study revealed all stakeholders having positive attitudes toward the provision of sexual health education in secondary schools. Results also revealed participants in favour of adolescents being taught several topics except for homosexuality. Findings on the appropriate age to start learning sexual health education revealed participants having trouble in fixing the right age, however, they said, at least 5 through 10 years before a child initiates sexual activity. Conclusion: The study concludes that stakeholders in the study areas have a positive attitude towards the provision of sexual health education in secondary schools and want students to be taught a wide range of topics before they initiate sexual activity. It is recommended that age-appropriate comprehensive sexuality education be given to teenagers to provide them with the knowledge they need to make informed decisions about their sexuality. This requires concerted efforts from the school, government and community involvement in the provision of sexual health education to in-school adolescents.

Socio-environmental predictors of diabetes incidence disparities in Tanzania mainland: a comparison of regression models for count data.

BACKGROUND: Diabetes is one of the top four non-communicable diseases that cause death and illness to many people around the world. This study aims to use an efficient count data model to estimate socio-environmental factors associated with diabetes incidences in Tanzania mainland, addressing lack of evidence on the efficient count data model for estimating factors associated with disease incidences disparities. METHODS: This study analyzed diabetes counts in 184 Tanzania mainland councils collected in 2020. The study applied generalized Poisson, negative binomial, and Poisson count data models and evaluated their adequacy using information criteria and Pearson chi-square values. RESULTS: The data were over-dispersed, as evidenced by the mean and variance values and the positively skewed histograms. The results revealed uneven distribution of diabetes incidence across geographical locations, with northern and urban councils having more cases. Factors like population, GDP, and hospital numbers were associated with diabetes counts. The GP model performed better than NB and Poisson models. CONCLUSION: The occurrence of diabetes can be attributed to geographical locations. To address this public health issue, environmental interventions can be implemented. Additionally, the generalized Poisson model is an effective tool for analyzing health information system count data across different population subgroups.

Assessing the effects of mosquito nets on malaria mortality using a space time model: a case study of Rufiji and Ifakara Health and Demographic Surveillance System sites in rural Tanzania.

BACKGROUND: Although malaria decline has been observed in most sub-Saharan African countries, the disease still represents a significant public health burden in Tanzania. There are contradictions on the effect of ownership of at least one mosquito net at household on malaria mortality. This study presents a Bayesian modelling framework for the analysis of the effect of ownership of at least one mosquito net at household on malaria mortality with environmental factors as confounder variables. METHODS: The analysis used longitudinal data collected in Rufiji and Ifakara Health Demographic Surveillance System (HDSS) sites for the period of 1999-2011 and 2002-2012, respectively. Bayesian framework modelling approach using integrated nested laplace approximation (INLA) package in R software was used. The space time models were established to assess the effect of ownership of mosquito net on malaria mortality in 58 villages in the study area. RESULTS: The results show that an increase of 10 % in ownership of mosquito nets at village level had an average of 5.2 % decrease inall age malaria deaths (IRR = 0.948, 95 % CI = 0.917, 0.977) in Rufiji HDSS and 12.1 % decrease in all age malaria deaths (IRR = 0.879, 95 % CI = 0.806, 0.959) in Ifakara HDSS. In children under 5 years, results show an average of 5.4 % decrease of malaria deaths (IRR = 0.946, 95 % CI = 0.909, 0.982) in Rufiji HDSS and 10 % decrease of malaria deaths (IRR = 0.899, 95 % CI = 0.816, 0.995) in Ifakara HDSS. Model comparison show that model with spatial and temporal random effects was the best fitting model compared to other models without spatial and temporal, and with spatial-temporal interaction effects. CONCLUSION: This modelling framework is appropriate and provides useful approaches to understanding the effect of mosquito nets for targeting malaria control intervention. Furthermore, ownership of mosquito nets at household showed a significant impact on malaria mortality.

Spatial and space-time clustering of mortality due to malaria in rural Tanzania: evidence from Ifakara and Rufiji Health and Demographic Surveillance System sites.

BACKGROUND: Although, malaria control interventions are widely implemented to eliminate malaria disease, malaria is still a public health problem in Tanzania. Understanding the risk factors, spatial and space-time clustering for malaria deaths is essential for targeting malaria interventions and effective control measures. In this study, spatial methods were used to identify local malaria mortality clustering using verbal autopsy data. METHODS: The analysis used longitudinal data collected in Rufiji and Ifakara Health Demographic Surveillance System (HDSS) sites for the period 1999-2011 and 2002-2012, respectively. Two models were used. The first was a non-spatial model where logistic regression was used to determine a household's characteristic or an individual's risk of malaria deaths. The second was a spatial Poisson model applied to estimate spatial clustering of malaria mortality using SaTScan™, with age as a covariate. ArcGIS Geographical Information System software was used to map the estimates obtained to show clustering and the variations related to malaria mortality. RESULTS: A total of 11,462 deaths in 33 villages and 9328 deaths in 25 villages in Rufiji and Ifakara HDSS, respectively were recorded. Overall, 2699 (24 %) of the malaria deaths in Rufiji and 1596 (17.1 %) in Ifakara were recorded during the study period. Children under five had higher odds of dying from malaria compared with their elderly counterparts aged five and above for Rufiji (AOR = 2.05, 95 % CI = 1.87-2.25), and Ifakara (AOR = 2.33, 95 % CI = 2.05-2.66), respectively. In addition, ownership of mosquito net had a protective effect against dying with malaria in both HDSS sites. Moreover, villages with consistently significant malaria mortality clusters were detected in both HDSS sites during the study period. CONCLUSIONS: Clustering of malaria mortality indicates heterogeneity in risk. Improving targeted malaria control and treatment interventions to high risk clusters may lead to the reduction of malaria deaths at the household and probably at country level. Furthermore, ownership of mosquito nets and age appeared to be important predictors for malaria deaths.

Determinants of extramarital sex by men in Tanzania: a case study of Mbeya region.

This paper attempts to identify some factors associated with extramarital sex by men in the Mbeya region of Tanzania using data from a survey conducted in 2003/2004. The choice of Mbeya region was prompted by the fact that it has been found by previous studies to be one of the regions with the highest HIV prevalence rate in Tanzania. Correlates of extramarital sex that were considered include current age, education, residence, age at first sexual intercourse, age at first marriage and sex before marriage. A bivariate analysis of the survey data, which comprised a sample size of 568 married men aged between 15 and 62 years revealed statistically significant association between extramarital sex with current age, education, age at first intercourse and sex before marriage. The effect of these variables was tested through a multivariate logistic regression analysis and all the four independent variables were found to be statistically significant predictors of extramarital sex in Mbeya region.

Determinants of Extramarital Sex by Men in Tanzania: A Case Study of Mbeya region

This paper attempts to identify some factors associated with extramarital sex by men in the Mbeya region of Tanzania using data from a survey conducted in 2003/2004. The choice of Mbeya region was prompted by the fact that it has been found by previous studies to be one of the regions with the highest HIV prevalence rate in Tanzania. Correlates of extramarital sex that were considered include current age; education; residence; age at first sexual intercourse; age at first marriage and sex before marriage. A bivariate analysis of the survey data; which comprised a sample size of 568 married men aged between 15 and 62 years revealed statistically significant association between extramarital sex with current age; education; age at first intercourse and sex before marriage. The effect of these variables was tested through a multivariate logistic regression analysis and all the four independent variables were found to be statistically significant predictors of extramarital sex in Mbeya region

Socio-demographic correlates of desire for HIV testing in Tanzania.

BACKGROUND: Over 60% of women and men interviewed in the Tanzania Demographic Health Survey (TDHS) of 1996 and the Tanzania Reproductive and Child Health Survey (TRCHS) of 1999 indicated that they would like to be tested for AIDS virus (HIV-antibody test). This is encouraging in view of the fact that voluntary HIV testing coupled with appropriate counselling is now believed to be quite effective for the prevention of HIV infection. This paper seeks to identify some socio-demographic factors that are associated with desire for HIV testing in Tanzania. METHODS: The study used data from the 1999 Tanzania Reproductive and Health Survey in which 4029 women and 3542 men were interviewed. A logistic regression analysis was used to identify correlates of desire for HIV testing for both men and women. RESULTS: For both men and women the logistic regression results show that significant correlates of desire for HIV testing are education, residence and knowledge of HIV prevention. In particular the odds of desire for AIDS test were found to be lower for respondents with secondary school education than those with primary school education. The odds were also significantly lower for urban respondents than for rural ones. The findings further show that the odds of desire for having an AIDS test were lowest for respondents with no knowledge of HIV prevention. CONCLUSIONS: Strategic campaigns to convince people to go for HIV testing should put more emphasis on radio programmes since these are effective means of communication in rural areas where desire for testing seems to be high. Such programmes should also focus on raising awareness on HIV prevention. HIV testing facilities should also be extended to the rural areas and be offered at affordable prices.

Correlates of knowledge of prevention of sexually transmitted diseases among primary school pupils in Tanzania.

In this paper we attempt to identify factors that determine knowledge on prevention of sexually transmitted diseases (STDs) among primary school pupils in Tanzania using data extracted from the Family Life Education KAP Survey conducted in 1999. The data used consist of a sample of 18,564 pupils (about 50% males and 50% females) from all the 20 regions of Tanzania mainland. There were significant differences between boys and girls as regards knowledge of family life education in general. Boys tended to be more knowledgeable than girls about many aspects of family life education. The findings show that only 40.1% of the respondents were able to identify all the three STDs given in the questionnaire namely gonorrhoea, syphilis and AIDS. As regards modes of HIV transmission only 37.5% had full knowledge of these, while 48.8% knew condom use and abstinence as methods of STD prevention. The bivariate analysis showed significant relationships between knowledge of condom use and abstinence as methods of STD prevention with knowledge of STDs, HIV transmission, education level of the respondents, residence and parents' education for both boys and girls. However, knowledge of STDs, HIV transmission and residence came out clearly in the logistic regression as predictors of knowledge of condom use as a method of STD prevention for both sexes. For males, mother's education was also a significant predictor of knowledge of condom use as a method of STD prevention. Furthermore, a significant predictor of knowledge of condom use for female respondents was found to be the respondent's educational level. On the other hand, predictors of knowledge of abstinence as a method of STD prevention were knowledge of STDs and HIV transmission.