The evolving burden of HIV infection compared with other chronic diseases in northern Italy

Objectives: The aim of the study was to estimate the burden and direct costs of diseases in HIV-infected patients (either opportunistic illnesses or other chronic diseases) with respect to the HIV-uninfected population. These estimates will be useful for the projection of future direct costs of HIV care.

Patients and methods: A population-based study was conducted in the Brescia Local Health Agency in northern Italy. An administrative database recorded diagnoses, deaths, drug prescriptions and health resource utilization for all medical and surgical patients in the region from 2003 to 2007. The study estimated the prevalence of HIV infection as well as HIV-related mortality and annual cost per patient, and compared mortality and costs related to HIV infection with those for a set of 15 other chronic diseases. The standardized hazard ratio (SHR) and standardized mortality ratio (SMR) were obtained using an indirect standardization method.

Results: The prevalence of HIV infection increased from 218 per 100,000 inhabitants in 2003 to 263 per 100,000 in 2007. Although mortality rates decreased markedly (from 24 per 1000 HIV-infected patients in 2003 to 16 per 1000 in 2007), the data show that mortality was still higher in HIV-infected patients compared with the general population in the most recent years (SMR 8.8 in 2007). In each year included in the study, HIV-infected patients had higher rates of care-seeking for chronic diseases, including liver diseases (SHR>8), neuropathy, oesophagus-gastro-duodenum diseases, serious psychiatric disorders and renal failure (SHR approximately 3 for each). Also, the rate of medical attendance for neoplasias, chronic pulmonary disease, diabetes, and cardiovascular disease increased over time in HIV-infected patients compared with the general population. Ranking diseases in order of their total cost to the health system, HIV infection ranked 12th, with total costs of €28.6 million in 2007. Ranking in order of cost per patient, HIV infection ranked third, with a cost per patient of €9894 in 2007. HIV-infected patients with concomitant chronic diseases had higher average costs. The cost per patient in 2007 was €8104 for HIV-infected patients without other chronic diseases, €9908 for HIV infection plus cardiovascular disease, €11,370 for HIV infection plus chronic liver disease and €12,013 for HIV infection plus neoplasias.

Conclusions: The prevalence and population cost of people living with HIV are likely to increase as a result of prolonged survival, aging of HIV-infected patients and increased risk of other chronic diseases. In the near future, HIV infection will rank as one of the most costly chronic diseases. Prevention strategies need to be more widely adopted to control the growing burden of the HIV epidemic and other chronic diseases affecting HIV-infected patients.