No excess risk of follicular lymphoma in kidney transplant and HIV-related immunodeficiency.

Subtype-specific incidence patterns in populations at high risk of lymphoma offer insight into lymphomagenesis. The incidence profiles for the 2 most common non-Hodgkin lymphoma subtypes were compared for 2 immunodeficient populations, adults receiving a kidney transplant 1982-2003 (n = 7,730) or diagnosed with human immunodeficiency virus (HIV) infection 1982-2004 (n = 17,175). National, population-based registries were linked and standardized incidence ratios (SIRs) were computed for each cohort and lymphoma subtype. Risk of diffuse large B-cell lymphoma was significantly increased after transplantation (SIR 17.83, 95% CI: 13.61-22.95) and after HIV infection (SIR 58.81, 95% CI: 52.59-65.56). Rates of follicular lymphoma (FL) were neither significantly increased nor decreased in transplant recipients (SIR 0.82, 95% CI: 0.10-2.96) and in people with HIV (SIR 1.25, 95% CI: 0.41-2.91). The findings argue against an infectious or other immunodeficiency-related etiology for FL and clearly differentiate it from diffuse large B-cell lymphoma.

Continuing declines in some but not all HIV-associated cancers in Australia after widespread use of antiretroviral therapy.

OBJECTIVE: To describe changes in cancer incidence in people with HIV in Australia since the introduction of highly active antiretroviral therapy (HAART). DESIGN: Population-based, retrospective cohort study of people with HIV (n = 20 232) using data linkage between national registers of HIV/AIDS and cancer in 1982-2004. METHODS: Age-adjusted and sex-adjusted incidence rate ratios with 95% confidence intervals were calculated to compare site-specific cancer incidence during the early (1996-1999) and late (2000-2004) HAART periods with that prior to HAART (1982-1995). Five-year age-specific, sex-specific, calendar year-specific, and state-specific standardized incidence ratios with 95% confidence interval were also calculated for each period. RESULTS: Incidence of Kaposi sarcoma and non-Hodgkin lymphoma declined significantly (Ptrend < 0.001). Incidence of Hodgkin lymphoma was significantly higher during the early-HAART period (incidence rate ratio 2.34, 95% confidence interval 1.19-4.63) but declined thereafter (Pdiff = 0.014). Incidence of anal cancer was unchanged (Ptrend = 0.451) and remained raised more than 30-fold. Incidence declined significantly for melanoma (Ptrend = 0.041) and prostate cancer (Ptrend = 0.026), and, during the late-HAART period, was lower than in the general population for both cancers. Incidence of colorectal cancer was consistently lower than in the general population. CONCLUSION: Incidence of Kaposi sarcoma and non-Hodgkin lymphoma has continued to decline among people with HIV in Australia, though it remains very substantially elevated. Incidence of Hodgkin lymphoma may now also be declining. Incidence of anal cancer has remained stable, and it is now the third most common cancer in HIV-infected Australians. Reasons for the reduced incidence of colorectal and prostate cancer, and more recently of melanoma, are unclear.

Perinatal exposure to HIV among children born in Australia, 1982-2006.

OBJECTIVE: To describe the pattern of perinatal HIV exposure and outcomes among children born in Australia, 1982-2006. DESIGN AND SETTING: National surveillance for perinatal HIV exposure. PARTICIPANTS: Women with HIV infection and their perinatally exposed children. MAIN OUTCOME MEASURES: Trends in the age-standardised rate of perinatal exposure, uptake of interventions by women with an antenatal HIV diagnosis, and rate of mother-to-child transmission. RESULTS: Between 1982 and 2006, there were 354 reported cases of perinatal HIV exposure among children born in Australia. The age-standardised rate of perinatal exposure per 100,000 live births increased from 2.3 (1982-1986) to 5.1 (1991-1998), 9.9 (1999-2002) and 8.3 (2003-2006). Among children whose mother was diagnosed antenatally, the mother-to-child transmission rate declined significantly, from 25% (4/16; 95% CI, 7%-52%) in 1987-1990 to 5% (4/82; 95% CI, 1%-12%) in 2003-2006 (P < 0.001). The rate declined from 8% (4/51; 95% CI, 2%-19%) in 1987-1998 to 1% (2/151; 95% CI, 0.2%-5%) in 1999-2006 among children whose mother used at least two interventions. Mother-to-child transmission remained high among children born to women diagnosed postnatally (39/87, 45%; 95% CI, 34%-56%) and to women diagnosed antenatally who used no interventions (7/15, 47%; 95% CI, 21%-73%). CONCLUSION: The increasing rate of perinatal exposure and the decreasing rate of mother-to-child transmission among children whose mothers' HIV infection was diagnosed antenatally were temporally associated with use of interventions for minimising mother-to-child transmission. Mother-to-child transmission remained high when the mother's HIV infection was not known during pregnancy.

Rapidly ageing HIV epidemic among men who have sex with men in Australia.

BACKGROUND: Antiretroviral therapy has increased survival for individuals living with HIV and has led to an ageing of this population in developed countries. To date the rate of ageing has been unquantified, giving rise to uncertainty in the treatment emphasis and burden in this population. METHODS: A mathematical model was used in conjunction with HIV/AIDS data from the Australian National HIV/AIDS Registry to estimate numbers and ages of Australian men who have sex with men (MSM) living with HIV infection from 1980 to 2005. RESULTS: The average age of HIV-infected Australian MSM is estimated to exceed 44 years of age by the year 2010 and has increased by 1 year of age for each two calendar years since the mid-1980s. HIV-infected MSM over 60 years of age have been increasing in number by 12% per year since 1995. A consequence of successful therapy with subsequent ageing of those infected has meant that from 2001 estimated deaths from other causes exceed AIDS deaths in Australia. CONCLUSIONS: In summary, our analyses indicate an increasing and rapidly ageing population living with HIV in Australia. This will inevitably lead to more serious non-AIDS conditions in ageing patients living with HIV, and to increased treatment complexity.

Variable uptake of recommended interventions to reduce mother-to-child transmission of HIV in Australia, 1982-2005.

OBJECTIVE: To analyse the uptake of interventions known to reduce the risk of perinatal HIV transmission among Australian women with HIV infection (who knew their HIV status before delivery), and identify predictors of uptake. DESIGN: Retrospective analysis of perinatal HIV surveillance data in Australia. PATIENTS: Women reported as having HIV infection and having given birth to a child (1982-2005) were identified through three mechanisms: an informal network of clinicians (1982-1993); an active surveillance program through paediatricians (since 1993); and state health department reports of children born to women newly diagnosed with HIV (since 1995). MAIN OUTCOME MEASURES: Uptake of interventions - avoidance of breastfeeding (after 1985), use of zidovudine during pregnancy (after 1994), and elective caesarean section (after 1999). Factors associated with uptake of these interventions were identified by univariate and multivariate analyses. RESULTS: 367 live births were reported in 291 women with HIV infection. Among the subgroup diagnosed with HIV infection before delivery, 4/255 (1.6%) elected to breastfeed (post 1985), 44/185 (24%) did not receive zidovudine (after 1994), and 41/118 (35%) did not have an elective caesarean section (after 1999). In multivariate analysis, there were significant differences in uptake of zidovudine and elective caesarean section according to year of birth and state in which the birth took place. CONCLUSION: In Australia between 1982 and 2005, uptake of interventions to reduce mother-to-child transmission of HIV was high. There were significant differences associated with use of zidovudine and mode of delivery according to location of delivery and year of birth.

Characteristics of HIV diagnoses in Australia, 1993-2006.

OBJECTIVE: To describe recent trends in the diagnosis of HIV infection in Australia. METHODS: National HIV surveillance data from 1993 to 2006 were analysed with a focus on geographic differences by HIV exposure route and late presentation (HIV within 3 months of a first AIDS-defining illness or a CD4 count of less than 200 cells muL(-1)). RESULTS: In 1993-99, the number of HIV diagnoses declined by 32%, and then increased by 39% from 1999 to 2006. From 2000 onwards, rates increased significantly in Victoria, Queensland, South Australia and Western Australia. The most frequently reported routes of HIV exposure were male to male sex (71%) and heterosexual contact (18%), and the population rate of diagnoses have increased in both categories. Among the cases reported as heterosexually acquired (n = 2199), 33% were in people born in a high-prevalence country and 19% in those with partners from a high-prevalence country. Late presentation was most frequent in heterosexually acquired infections in persons who had a partner from a high-prevalence country: 32% compared with 20% overall. CONCLUSIONS: Recent increases in annual numbers of HIV diagnoses in Australia underline the continuing need for HIV-prevention programs, particularly among men having male to male sex. Early diagnosis and access to care and treatment should also be emphasised, as a substantial proportion of people with HIV infection are unaware of their status until late in the course of disease.

Could sexually transmissible infections be contributing to the increase in HIV infections among men who have sex with men in Australia?

BACKGROUND: To review existing data on sexually transmissible infections (STI) in men who have sex with men in Australia in order to determine the possible contribution of STI to diverging trends in HIV notifications in different states. METHODS: We reviewed data from multiple sources, including routine national surveillance data, laboratory surveillance data, self-reported information on STI testing in men who have sex with men and ad hoc reports of STI prevalence. RESULTS: We found increasing rates of gonorrhoea and infectious syphilis notifications in urban men in Australia between 1997 and 2006, and increasing rates of chlamydia notifications in men aged 30-49 years. There was little difference in these trends by state. Differences in the population groups sampled meant we were unable to gain further information on trends in men who have sex with men from these studies. Data on STI testing showed an increase in anal STI testing between 2003 and 2006, which may have increased the number of diagnoses of chlamydia and gonorrhoea for men who have sex with men during this period. CONCLUSIONS: Over the past 10 years, there has been a substantial increase in diagnoses of gonorrhoea and infectious syphilis, and probably chlamydia, in men who have sex with men in Australia. However, it is unlikely that changes in the pattern of STI transmission are responsible for the recent divergence in HIV rates between Australian states because there is little evidence that trends in STI also differ by state.

HIV diagnoses in Australia: diverging epidemics within a low-prevalence country.

OBJECTIVE: To describe recent trends in the diagnosis of HIV infection in Australia. DESIGN AND SETTING: Analysis of national surveillance system data for 1993-2006. MAIN OUTCOME MEASURES: Number and population rate of new HIV diagnoses by year, exposure route and demographic characteristics. RESULTS: Between 1993 and 2006, 12 313 new diagnoses of HIV infection were reported in Australia. From 1993 to 1999, the annual number of diagnoses declined by 32% from 1056 to 718, and then increased by 31% from 763 in 2000 to 998 in 2006. Between 2000 and 2006, diagnosis rates significantly increased in Victoria, Queensland, South Australia and Western Australia. The most frequent route of HIV exposure was male-to-male sex, accounting for 70% of diagnoses. Heterosexual contact accounted for 18% of cases, with just over half of these people born in or having a sexual partner from a high-prevalence country. Exposure by injecting drug use remained infrequent. CONCLUSIONS: The number of HIV diagnoses has risen in the past 7 years, but not in New South Wales, which has long had the highest rates. The differences in rates between states/territories are likely to be due to divergent trends in sexual risk behaviour in men having male-to-male sex, which remains the predominant route of HIV transmission in Australia. There is a need for effective, innovative and evidence-based programs for HIV prevention, particularly among men having male-to-male sex.

Would universal antenatal screening for HIV infection be cost-effective in a setting of very low prevalence? Modelling the data for Australia.

BACKGROUND: The economics of universal antenatal human immunodeficiency virus (HIV) screening should be explored if mother-to-child transmission of HIV occurs, the health-service infrastructure for universal screening exists, and optimal risk-reducing treatments can be supplied. METHODS: We evaluated a hypothetical cohort of the antenatal population of Australia during 2001-2002, to examine whether universal antenatal HIV screening is cost-effective in this setting. A quasi-societal perspective was adopted, secondary data sources were used, and sensitivity analyses were undertaken. Costs and benefits incurred in the future were discounted to their present value. RESULTS: The intervention would be cost-effective if the prevalence of undiagnosed HIV in the currently unscreened Australian antenatal population was >or=0.004372%. We predict 6.95 new diagnoses of HIV, 1.73 infections avoided, and 46.97 discounted-life-years gained. Applying favorable and unfavorable values for key variables suggests that the prevalence at which the intervention would be cost-effective is 0.0016%-0.0106%. CONCLUSIONS: Universal antenatal HIV screening would be cost-effective at a very low prevalence and would generate net benefits under many scenarios; accurate statistics on the true prevalence of HIV in the currently unscreened antenatal population are required.

Late HIV presentation among AIDS cases in Australia, 1992-2001.

OBJECTIVE: To describe time trends and demographic, exposure and clinical factors associated with late HIV presentation among notified AIDS cases diagnosed in Australia in 1992-2001. METHODS: AIDS cases, diagnosed in Australia and notified to the National AIDS Registry, were included in the analysis. AIDS cases newly diagnosed with HIV infection within three months of AIDS diagnosis were defined as cases of late HIV presentation. RESULTS: The percentage of AIDS cases with late HIV presentation increased significantly from 18% in 1992-96 to 33.1% in 1997 (adjusted odds ratio (AOR)=1.79, p<0.005) and to 49.6% in 2001 (AOR=3.01, p<0.005). Older age, having been born in Asia, a HIV exposure history of heterosexual contact or an 'other/undetermined' exposure and a diagnosis of PCP only or of multiple AIDS illnesses, were associated with late HIV presentation among AIDS cases diagnosed in 1992-96 and in 1997-2001, and among overseas-born cases diagnosed in 1992-2001. In 1997-2001, a low CD4+ cell count was also associated with late HIV presentation. Among homosexually active men diagnosed with AIDS in 1997-2001, older age, a diagnosis of PCP or multiple AIDS illnesses and a low CD4+ cell count were associated with late HIV presentation. CONCLUSION: Predictors of late HIV presentation have remained substantially unchanged over time and among population subgroups, suggesting a need for innovation in HIV/AIDS testing and counselling strategies.