Lars Haukali Omland

Incidence, Clinical Presentation, and Outcome of Progressive Multifocal Leukoencephalopathy in HIV-Infected Patients during the Highly Active Antiretroviral Therapy Era: A Nationwide Cohort Study

BACKGROUND Human immunodeficiency virus (HIV) infection predisposes to progressive multifocal leukoencephalopathy (PML). Here, we describe the incidence, presentation, and prognosis of PML in HIV-1-infected patients during the period before highly active antiretroviral therapy (HAART) (1995-1996) and during the early HAART (1997-1999) and late HAART (2000-2006) periods. METHODS Patients from a nationwide population-based cohort of adult HIV-1-infected individuals were included. We calculated incidence rates of PML and median survival times after diagnosis. We also described neurological symptoms at presentation and follow-up. RESULTS Among 4,649 patients, we identified 47 patients with PML. The incidence rates were 3.3, 1.8, and 1.3 cases per 1000 person-years at risk in 1995-1996, 1997-1999, and 2000-2006, respectively. The risk of PML was significantly associated with low CD4(+) cell count, and 47% of cases were diagnosed by means of brain biopsy or polymerase chain reaction analysis for JC virus. The predominant neurological symptoms at presentation were coordination disturbance, cognitive defects, and limb paresis. Thirty-five patients died; the median survival time was 0.4 years (95% confidence interval [CI], 0.0-0.7) in 1995-1996 and 1.8 years (95% CI, 0.6-3.0) in both 1997-1999 and 2000-2006. CD4(+) cell count >50 cells/microL at diagnosis of PML was significantly associated with reduced mortality. CONCLUSIONS The incidence of PML in HIV-infected patients decreased after the introduction of HAART. Survival after PML remains poor. In the management of PML, the main focus should be on prophylactic measures to avoid immunodeficiency.

Impact of Non-HIV and HIV Risk Factors on Survival in HIV-Infected Patients on HAART: A Population-Based Nationwide Cohort Study

Background We determined the impact of three factors on mortality in HIV-infected patients who had been on highly active antiretroviral therapy (HAART) for at least one year: (1) insufficient response to (HAART) and presence of AIDS-defining diseases, (2) comorbidity, and (3) drug and alcohol abuse and compared the mortality to that of the general population. Methodology/Principal Findings In a Danish nationwide, population-based cohort study, we used population based registries to identify (1) all Danish HIV-infected patients who started HAART in the period 1 January 1998–1 July 2009, and (2) a comparison cohort of individuals matched on date of birth and gender (N = 2,267 and 9,068, respectively). Study inclusion began 1 year after start of HAART. Patients were categorised hierarchically in four groups according to the three risk factors, which were identified before study inclusion. The main outcome measure was probability of survival from age 25 to 65 years. The probability of survival from age 25 to age 65 was substantially lower in HIV patients [0.48 (95% confidence interval (CI) 0.42–0.55)] compared to the comparison cohort [0.88 (0.86 to 0.90)]. However, in HIV patients with no risk factors (N = 871) the probability of survival was equivalent to that of the general population [0.86 (95% CI 0.77–0.92)]. In contrast, the probability of survival was 0.58 in patients with HIV risk factors (N = 704), 0.30 in patients with comorbidities (N = 479), and 0.03 in patients with drug or alcohol abuse (N = 313). Conclusions The increased risk of death in HIV-infected individuals is mainly attributable to risk factors that can be identified prior to or in the initial period of antiretroviral treatment. Mortality in patients without risk factors on a successful HAART is almost identical to that of the non–HIV-infected population.

Mortality in patients with chronic and cleared hepatitis C viral infection: A nationwide cohort study

BACKGROUND & AIMS It is unknown whether mortality differs between patients with chronic hepatitis C virus (HCV) replication and those who cleared the virus after infection. We examined the impact of chronic HCV replication on mortality among Danish patients testing positive for HCV antibodies. METHODS This nationwide cohort study focused on Danish patients with at least one HCV RNA measurement available after testing positive for HCV antibodies between 1996 and 2005. To capture long-term prognosis, eligible patients needed to be alive 1year after HCV RNA assessment. We estimated mortality rate ratios (MRRs) using Cox regression (for overall mortality) and subdistribution hazard ratios (SDHRs) for cause-specific mortality, controlling for gender, age, comorbidity, calendar period, alcohol abuse, injection drug use, and income. RESULTS Of the 6292 patients under study, 63% had chronic HCV-infection and 37% had cleared the virus. Five-year survival was 86% (95% confidence interval (CI): 84-87%) in the chronic HCV group and 92% (95% CI: 91-94%) in the cleared HCV group. Chronic HCV-infection was associated with higher overall mortality (MRR: 1.55, 95% CI: 1.28-1.86) and liver-related death (SDHR: 2.42, 95% CI: 1.51-3.88). Chronic HCV-infection greatly increased the risk of death from primary liver cancer (SDHR: 16.47, 95% CI: 2.24-121.00). CONCLUSIONS Patients with chronic HCV-infection are at higher risk of death than patients who cleared the infection. The substantial association found between chronic HCV-infection and death from primary liver cancer supports early initiation of antiviral treatment in chronically HCV-infected patients.

Incidence and Impact on Mortality of Severe Neurocognitive Disorders in Persons With and Without HIV Infection: A Danish Nationwide Cohort Study

OBJECTIVE The risk of neurocognitive disorders in human immunodeficiency virus (HIV)-infected patients in the era of highly active antiretroviral therapy (HAART) is controversial. We aimed to compare the incidence and impact on mortality of severe neurocognitive disorders (SNCDs) in HIV-infected patients with that of the background population. METHODS The method used was a nationwide, population-based cohort study using Danish registries. We calculated incidence rates, incidence rate ratios, mortality rate ratios, and Kaplan-Meier tables to estimate the incidence of and survival after SNCD in HIV-infected patients, compared with a general population control cohort matched by age and sex. RESULTS We observed 32 cases of SNCDs among 4452 HIV-infected patients and 120 cases of SNCDs among 62 328 population control subjects. The overall risk of SNCD among HIV-infected patients was 1.0 case per 1000 person-years (PYR), compared with 0.23 cases per 1000 PYR for population control subjects but became 0.35 cases/1000 PYR after 2004, compared with 0.27 cases/1000 PYR in population control subjects. The absence of HAART and a low CD4 lymphocyte count increased the risk of SNCD. The mortality among HIV-infected patients with SNCD was higher than that among population controls with SNCD (median survival, 4.3 years vs 9.7 years [P = .02]). CONCLUSION HIV-infected patients have an increased risk of SNCD, but the risk is low and has, in recent years, become comparable to that seen in the background population. In contrast, the mortality remains high among HIV-infected patients diagnosed with SNCD.

Impact of hepatitis B virus co‐infection on response to highly active antiretroviral treatment and outcome in HIV‐infected individuals: a nationwide cohort study

The impact of chronic hepatitis B virus (HBV) infection on viral suppression, immune recovery and mortality in HIV‐1 infected patients on highly active antiretroviral treatment (HAART) is a matter of debate. The impact of HBeAg status is unknown.

Hepatitis C prevalence in Denmark -an estimate based on multiple national registers

BackgroundA national survey for chronic hepatitis C has not been performed in Denmark and the prevalence is unknown. Our aim was to estimate the prevalence of chronic hepatitis C from public registers and the proportion of these patients who received specialized healthcare.MethodsPatients with a diagnosis of chronic hepatitis C were identified from four national registers: a laboratory register, the Hospital Discharge Register, a clinical database of chronic viral hepatitis and the Register of Communicable Diseases. The total population diagnosed with hepatitis C was estimated by capture-recapture analysis. The population with undiagnosed hepatitis C was derived from the national register of drug users by comparing diagnosed and tested persons.ResultsA total of 6,935 patients diagnosed with chronic hepatitis C were identified in the four registers and the estimated population diagnosed with the disease was 9,166 persons (95% C.I. interval 8,973 – 9,877), corresponding to 0.21% (95% CI 0.21%-0.23%) of the Danish population over 15years of age. The prevalence was highest among persons 40–49years old (0.39%) and males (0.28%). It was estimated that 40% of the diagnosed patients lived in the capital region, and 33.5% had attended specialised healthcare. It was estimated that 46% of hepatitis C patients had not been diagnosed and the total population with chronic hepatitis C in Denmark was 16,888 (95% C.I. 16,474-18,287), corresponding to 0.38% (95% CI 0.37-0.42) of the population over 15years of age.ConclusionsThe estimated prevalence of chronic hepatitis C in Denmark was 0.38%. Less than half of the patients with chronic hepatitis C in Denmark have been identified and among these patients, one in three has attended specialised care.

Increased Mortality Among Persons Infected With Hepatitis C Virus

BACKGROUND & AIMS The long-term mortality of patients infected with hepatitis C virus (HCV) is not known; few studies have controlled for potential confounders, investigated how mortality changes with age at diagnosis and length of follow-up period, provided absolute risk estimates of death, or analyzed specific causes of death. METHODS Using a Danish population, we compared mortality of a cohort of 10,991 HCV-infected patients with that of an age- and sex-matched cohort. Using regression analysis, we adjusted for municipality of residence, history of psychiatric illness, comorbidities, alcohol and drug abuse, and income. We analyzed causes of death and effects of HCV with age and length of follow-up period. RESULTS HCV-infected patients had lower income levels and more comorbidities, psychiatric illnesses, and substance and alcohol abuse than the comparison cohort. The 10-year survival rate decreased from 84.1% among HCV-infected patients aged 20 to 29 years to 21.1% among those aged 70 years or older. The increased risk of death among HCV-infected patients was more pronounced in the first year of follow-up period than in subsequent years and in the unadjusted than in the adjusted analysis. Starting in the second year of the follow-up period, HCV-infected patients aged 20 to 29 years had an 18.2-fold increased risk of death, whereas those that were 70 years or older had a 1.6-fold increased risk. Most deaths among younger patients were from unnatural causes, and most deaths among patients 70 years or older were from non-liver-related natural causes. CONCLUSIONS HCV infection is associated with increased mortality; younger patients (age, 20-29 y) have an increased risk of unnatural death.

Impact of injecting drug use on mortality in Danish HIV-infected patients: a nation-wide population-based cohort study.

OBJECTIVES To estimate the impact of injecting drug use (IDU) on mortality in HIV-infected patients in the highly active antiretroviral therapy (HAART) era. DESIGN Population-based, nation-wide prospective cohort study in Denmark (the Danish HIV Cohort Study). METHODS A total of 4578 HIV-infected patients were followed from 1 January 1997 or date of HIV diagnosis. We calculated mortality rates stratified on IDU. One-, 5- and 10-year survival probabilities were estimated by Kaplan-Meier methods, and Cox regression analyses were used to estimate mortality rate ratios (MRR). RESULTS Of the patients, 484 (10.6%) were categorized as IDUs and 4094 (89.4%) as non-IDUs. IDUs were more likely to be women, Caucasian, hepatitis C virus (HCV) co-infected and younger at baseline; 753 patients died during observation (206 IDUs and 547 non-IDUs). The estimated 10-year survival probabilities were 53.2% [95% confidence interval (CI): 48.1-58.3] in the IDU group and 82.1% (95% CI: 80.7-83.6) in the non-IDU group. IDU as route of HIV infection more than tripled the mortality in HIV-infected patients (MRR: 3.2; 95% CI: 2.7-3.8). Adjusting for potential confounders did not change this estimate substantially. The risk of HIV-related death was not increased in IDUs compared to non-IDUs (MRR 1.1; 95% CI 0.7-1.7). CONCLUSIONS Although Denmarks health care system is tax paid and antiretroviral therapy is provided free of charge, HIV-infected IDUs still suffer from substantially increased mortality in the HAART era. The increased risk of death seems to be non-HIV-related and is due probably to the well-known risk factors associated with intravenous drug abuse.

Hepatitis C virus infection and risk of cancer: a population-based cohort study.

Background: Hepatitis C virus (HCV) infection is associated with an increased risk of primary liver cancer; however, 5- and 10-year risk estimates are needed. The association of HCV with non-Hodgkin lymphoma (NHL) is uncertain and the association with other cancers is unknown. Method: We conducted a nationwide, population-based cohort study of 4,349 HCV-infected patients in Denmark, computing standardized incidence ratios (SIR) of cancer incidence in HCV infected patients compared with cancer incidence of the general population. We calculated 5- and 10-year risks of developing cancer, stratifying our analyses based on the presence of HIV coinfection and cirrhosis. Results: We recorded an increased risk of primary liver cancer (SIR: 76.63 [95% CI: 51.69–109.40]), NHL (SIR: 1.89 [95% CI: 0.39–5.52]), and several smoking- and alcohol-related cancers in HCV infected patients without HIV coinfection. HCV-infected patients without HIV coinfection had a 6.3% (95% CI: 4.6%–8.7%) risk of developing cancer and 2.0% (95% CI: 1.1%–3.8%) risk of developing primary liver cancer within 10 years. Conclusion: We confirmed the association of HCV infection with primary liver cancer and NHL. We also observed an association between HCV infection and alcohol- and smoking-related cancers.

Herpes simplex virus type 2 infections of the central nervous system: A retrospective study of 49 patients

Herpes simplex virus type 2 (HSV-2) infections of the central nervous system (CNS) are rare with meningitis as the most common clinical presentation. We have investigated the clinical spectrum of CNS infections in 49 adult consecutive patients with HSV-2 genome in the cerebrospinal fluid (CSF). HSV-2 in the CSF was determined by polymerase chain reaction (PCR), and patients were diagnosed as encephalitis or meningitis according to predefined clinical criteria by retrospective data information from consecutive clinical journals. The annual crude incidence rate of HSV-2 CNS disease was 0.26 per 100,000. 43 (88%) had meningitis of whom 8 (19%) had recurring lymphocytic meningitis. Six patients (12%) had encephalitis. 11 of 49 patients (22%) had sequelae recorded during follow-up. None died as a result of HSV-2 CNS disease. Thus, the clinical presentation of HSV-2 infection of the CNS is mainly meningitis but encephalitis does occur and neurological sequelae are common. Recurring lymphocytic meningitis is associated with reactivation of HSV-2 and the condition might be underdiagnosed.Herpes simplex virus type 2 (HSV-2) infections of the central nervous system (CNS) are rare with meningitis as the most common clinical presentation. We have investigated the clinical spectrum of CNS infections in 49 adult consecutive patients with HSV-2 genome in the cerebrospinal fluid (CSF). HSV-2 in the CSF was determined by polymerase chain reaction (PCR), and patients were diagnosed as encephalitis or meningitis according to predefined clinical criteria by retrospective data information from consecutive clinical journals. The annual crude incidence rate of HSV-2 CNS disease was 0.26 per 100,000. 43 (88%) had meningitis of whom 8 (19%) had recurring lymphocytic meningitis. Six patients (12%) had encephalitis. 11 of 49 patients (22%) had sequelae recorded during follow-up. None died as a result of HSV-2 CNS disease. Thus, the clinical presentation of HSV-2 infection of the CNS is mainly meningitis but encephalitis does occur and neurological sequelae are common. Recurring lymphocytic meningitis is associated with reactivation of HSV-2 and the condition might be underdiagnosed.