Factors Associated with Outcomes from Human Immunodeficiency Virus Infection. Summary of the Doctoral Thesis

Abstract

Background. AIDS incidence and mortality among people living with HIV (PLHIV) has continued to decrease in Europe over the past decade. Developments in treatment and care of HIV infected persons have increased their life expectancy close to the level of general population’s indicator. As HIV-specific mortality decreases, also main causes of death among PLHIV become similar to those causing the deaths in general population. Scientific literature frequently shows unequivocal information regarding the factors increasing the risk of AIDS and exitus letalis. In Latvia statistical significance of time trends of HIV outcome measures and the related factors among PLHIV have not been studied so far. As Latvia shows the highest AIDS incidence rate and third highest HIV-related mortality rate among European Union (EU) countries, HIV (and its outcomes) has to be considered as important public health threat in the country. Investigation of HIV outcome measures and associated factors may contribute the secondary and tertiary prevention issues in Latvia. The aim of the study was to examine causal and statistical associations between HIV outcome measures and sociodemographic, health behaviour, health status and health care factors. Methods. Data from National Registers (HIV/AIDS Cases; Causes of Death) as well as information from PLHIV medical record documentation was used for the time period of 1987-2010 (n=4,888). The total time of follow-up was 31,193 person years (py). Underlying causes of death were classified according to the ICD-10. Calculations of standardized mortality ratio were carried out using indirect standardization. Linear regression was used for time-trend analysis. For investigation of associated factors Cox proportional hazard and Poisson regression models were used. Data analysis was carried out using softwares MS Excel, SPSS 19.0 and CIA. Results. During the follow-up time 981 AIDS cases and 738 death cases were identified (35.4 and 23.7 / 1,000 py accordingly). AIDS incidence during the last 10 years is static (changes over the time are not significant – p=0.91). Crude mortality among PLHIV continues to increase 10% per year (p=0.002). Standardized mortality ratio (SMR) over the last 10 years still remains 5-13 times higher than among the general population and has a tendency to increase on average 7% per year (p=0.008). 5 year survival till AIDS is 83%, till exitus letalis – 89% (10 year survival 73% and 79% accordingly). 680 potential years of life have been lost per 1000 py (mean number per death – 29 years). HIV as the underlying cause of death was indicated in 51.4% of cases (11.4 / 1,000 py), besides the cause specific mortality rate increased by 25% per year over the last decade (p<0.001). The second prevailing group was external causes of death (21.7%; 4.8 / 1,000 py) and the third – cardiovascular diseases (9.4%; 2.1 / 1,000 py). Factors increasing the risk of HIV outcomes in general were gender (male), older age at time of diagnosis, ethnicity other than Latvian, injecting drug use, same-gender sex between men, more recent year of HIV diagnosis, late diagnosis, high levels of viral load and interruptions in antiretroviral therapy process. Females having experience of incarceration (vs. those who have not) have less years of potential life lost. Conclusions. In Latvia (as opposite to the average situation in EU) AIDS incidence is not decreasing and mortality (including HIV-specific) increases. HIV outcomes are associated with sociodemographic, health behaviour, health status as well as health care factors.