Rural Population-based Cohort Research Articles

Kaposi Sarcoma-Associated Herpesvirus in a Rural Ugandan Cohort, 1992-2008.

The prevalence and titers of antibodies against Kaposi sarcoma-associated herpesvirus (KSHV) in rural Africa are not completely understood, nor are their trends over time in populations in which human immunodeficiency virus (HIV) is also endemic. We examined prevalence, titers, temporal trends, and determinants of anti-KSHV antibodies in each of 3 time periods (1990-1991, 1999-2000, and 2007-2008) within a long-standing, rural population-based cohort in southwestern Uganda. For each period, we measured antibodies to the K8.1 and ORF73 KSHV antigens in approximately 3000 people of all ages (1:1 sex ratio). In all periods, KSHV prevalence increased rapidly through childhood to approximately 90% by age 15 years, plateauing at approximately 95% thereafter. Similarly, antibody titers, particularly against the lytic antigen K8.1, were among the highest seen and increased significantly with age, suggesting sustained viral replication in this population. Male sex was also independently associated with higher prevalence, whereas HIV coinfection was not. A modest reduction in prevalence among children was noted in the most recent period. KSHV seroprevalence and antibodies titers in this rural Ugandan population are the highest yet reported, perhaps reflecting frequent viral reactivation and persistently elevated transmission.

Stimulant Use, Religiosity, and the Odds of Developing or Maintaining an Alcohol Use Disorder Over Time

Little is known about whether cocaine or methamphetamine use, particularly among stimulant users residing in rural areas, is associated with increased odds of developing or maintaining an alcohol use disorder (AUD) over time. One factor that may help to protect some users against the development of an AUD is religiosity. This study examined how stimulant use and religiosity are associated longitudinally with the odds of an AUD among a rural population-based cohort of stimulant users. Recent stimulant users (N = 710) were recruited via respondent-driven sampling and were interviewed every 6 months over a 3-year period. Concurrent and lagged generalized estimating equations analyses were conducted to estimate how past-30- day crack cocaine, powder cocaine, and methamphetamine use; religiosity; and other covariates were associated with the odds of an AUD. At baseline, 56% of the participants met AUD criteria. The odds of an AUD declined significantly over time in the concurrent, but not the lagged, model. Crack cocaine use was associated with increased odds of an AUD in both models, although the strength of the concurrent association between an AUD and crack cocaine use declined over time. Powder cocaine use and more frequent church attendance also were concurrently associated with decreased odds of an AUD. Rural stimulant users, especially those using cocaine, could potentially benefit from treatment for both alcohol use and stimulant use. In addition, our findings suggest that greater frequency of church attendance may be related to lower odds of the development or maintenance of an AUD.

Prevalence of severe mental distress and its correlates in a population-based study in rural south-west Uganda

BackgroundThe problem of severe mental distress (SMD) in sub-Saharan Africa is difficult to investigate given that a substantial proportion of patients with SMD never access formal health care.This study set out to investigate SMD and it's associated factors in a rural population-based cohort in south-west Uganda.Methods6,663 respondents aged 13 years and above in a general population cohort in southwestern Uganda were screened for probable SMD and possible associated factors.Results0.9% screened positive for probable SMD. The factors significantly associated with SMD included older age, male sex, low socio-economic status, being a current smoker, having multiple or no sexual partners in the past year, reported epilepsy and consulting a traditional healer.ConclusionSMD in this study was associated with both socio-demographic and behavioural factors. The association between SMD and high risk sexual behaviour calls for the integration of HIV prevention in mental health care programmes in high HIV prevalence settings.

Septicaemia in a population-based HIV clinical cohort in rural Uganda, 1996-2007: incidence, aetiology, antimicrobial drug resistance and impact of antiretroviral therapy

To describe the incidence and aetiology of septicaemia, and antimicrobial drug resistance in HIV-infected and uninfected individuals, and the impact of antiretroviral therapy (ART) on septicaemia. Between 1996 and 2007, we followed up a rural population-based cohort of HIV-infected and uninfected participants. The aetiology and incidence of septicaemia, and antimicrobial drug resistances were determined. ART became available in 2004, and its impact on the incidence of septicaemia was examined. The overall septicaemia incidence (per 1000 pyrs) was 32.4 (95% CI 26.2-40.6) but was only 2.6 (95% CI 1.3-6.2) in HIV-negative patients and 67.1 (95% CI 53.4-85.4) in HIV-positive patients not on ART. Among those on ART, the overall incidence was 71.5 (95% CI 47.1-114.3), although it was 121.4 (95%CI 77.9-200.4) in the first year on ART and 37.4 (95%CI 18.9-85.2) in the subsequent period. Septicaemia incidence was significantly associated with lower CD4 counts. The commonest isolates were Streptococcus pneumoniae (SPN, n = 68) and Non-typhi salmonellae (NTS, n = 42). Most SPN isolates were susceptible to ceftriaxone and erythromycin, while resistance to cotrimoxazole and penicillin was common. All NTS isolates were susceptible to ciprofloxacin, but resistance to cotrimoxazole and chloramphenicol was common. Septicaemia incidence was higher in HIV-infected than in HIV-uninfected participants, and it remained high for some time among those who started ART. Starting ART earlier at higher CD4 counts is likely to lead to lower septicaemia incidence. Both SPN and NTS, the commonest isolates, were resistant to most commonly available antimicrobials. Blood culture laboratory surveillance systems to monitor antibiotic susceptibility and inform treatment guidelines are needed in Africa.

Adiposity measures and blood pressure in Chinese children and adolescents

Objective:To investigate the association of adiposity measures with blood pressure (BP) in Chinese children and adolescents.Design:A cross-sectional study.Participants:1330 boys and 1170 girls aged 6–18 years from a rural population-based cohort...

Does Parental Physical Violence Reduce Children's Standardized Test Score Performance?

Many negative cognitive and behavioral outcomes have been identified among children living in households with parental violence, but few studies have examined academic performance. In a rural population-based cohort, we examine the role of parental violence on standardized test score performance. The cohort included 306 children ages 6 through 17. Parents responded to a health interview that included questions about physical violence. Children's standardized test scores were collected prospectively for 5 years after the parent interview. Hierarchical multivariate models clustering on school, household, and repeated individual test scores and controlling for children's and parent's characteristics were run to predict test score performance. One in five children lived in a household in which parents reported at least one act of physical violence. Children whose parents reported intimate partner violence (IPV) performed an average of 12.2 percentile points lower than children whose parents reported no IPV (95% CI, -19.2--5.2; p < 0.001). Parent-reported IPV led to larger test score reductions for girls than for boys and for children less than 12 years old than for older children. Parental physical violence was common, and children in homes with violence had significantly poorer performance on standardized test scores.

Changing association between schooling levels and HIV‐1 infection over 11 years in a rural population cohort in south‐west Uganda

Previous studies have found that in Africa, a greater risk of HIV infection is often found in groups with higher educational attainment. However, some serial cross-sectional studies have found greater reductions in HIV prevalence among more educated groups, especially in cohorts of young adults. More recent studies have found some instances where higher schooling levels are associated with lower HIV prevalence. We describe changes in the association between schooling levels, HIV prevalence and condom use in a rural population-based cohort between 1989/1990 and 1999/2000, in Masaka District, Uganda. In 1989-1990, higher educational attainment was associated with higher risk of HIV-1 infection, especially among males, but once odds ratios are adjusted for age, no significant relation between schooling and HIV infection remains. In 1999-2000, there is, for females aged 18-29 years, a significant relationship between higher educational attainment and lower HIV prevalence, even after adjustment for age, gender, marital status and wealth (P for trend 0.01). Tests for interaction, significant for males and both genders combined, show that more schooling has been shifting towards an association with less HIV infection between 1989-1990 and 1999-2000, especially for young individuals. Condom use increased during the study period and this increase has been concentrated among more educated individuals. These findings suggest that over a decade more educated young adults, especially females, have become more likely to respond to HIV/AIDS information and prevention campaigns by effectively reducing their sexual risk behaviour.

The Rakai Project counselling programme experience.

During the initial survey (April 1999-January 2000) of an ongoing Community HIV Epidemiological Research (CHER) study, adults aged 15-49 years in 56 study communities were enrolled into the study. Knowledge, Attitude, Behaviour, Practice questionnaires were administered and blood was obtained from 77.6%. HIV testing was performed using two different enzyme immunosorbent assays with Western blot confirmation of discordant results and first time positives. All those who gave blood had free and unlimited access to voluntary counselling and testing (VCT), and were free to participate as individuals or couples. HIV results were provided in people's homes by trained and certified project resident counsellors. Ninety per cent of those who were bled requested their HIV results, while 64.6% of those who requested their HIV results received them. The proportion of people receiving HIV results has almost doubled in the last 6 years (1994-2000) from about 35% in 1994/1995 to 65% in 1999/2000. These data indicate high proportions of acceptance and receipt of VCT in this rural population-based cohort, suggesting that home delivery of VCT could offer a unique opportunity for people in the rural areas to access counselling and testing services, given adequate resources.

Declining HIV-1 incidence and associated prevalence over 10 years in a rural population in south-west Uganda: a cohort study

In Uganda, there have been encouraging reports of reductions in HIV-1 prevalence but not in incidence, which is the most reliable measure of epidemic trends. We describe HIV-1 incidence and prevalence trends in a rural population-based cohort between 1989 and 1999. We surveyed the adult population of 15 neighbouring villages for HIV-1 infection using annual censuses, questionnaires, and serological surveys. We report crude annual incidence rates by calendar year and prevalence by survey round. 6566 HIV-1 seronegative adults were bled two or more times between January, 1990, and December, 1999, contributing 31984 person years at risk (PYAR) and 190 seroconversions. HIV-1 incidence fell from 8.0 to 5.2 per 1000 PYAR between 1990 and 1999 (p=0.002, chi(2) for trend). Significant sex-specific and age-group-specific reductions in incidence were evident. Incidence was 37% lower for 1995-99 than for 1990-94 (p=0.002, t-test). On average, 4642 adult residents had a definite HIV-1 serostatus at each yearly survey round. HIV-1 prevalence fell significantly between the first and tenth annual survey rounds (p=0.03, chi(2) for trend), especially among men aged 20-24 years (6.5% to 2.2%) and 25-29 years (15.2% to 10.9%) and women aged 13-19 years (2.8% to 0.9%) and 20-24 years (19.3% to 10.1%) (all p<0.001, chi(2) for trend). Our findings of a significant drop in adult HIV-1 incidence in rural Ugandans give hope to AIDS control programmes elsewhere in sub-Saharan Africa where rates of HIV-1 infection remain high.

Indoor AirPollution Exposure and Lower Respiratory Infections in Young Gambian Children

In a rural population-based cohort study of approximately 500 Gambian children under five years old followed for one year, incidence of acute lower respiratory infections (ALR) was related to various risk factors including parental smoking and regular carriage on the mother's back while cooking, a proxy measure for exposure to smoke from cooking fires. Two statistical analyses using a 'child-weeks at risk' approach were carried out, including and excluding multiple disease episodes in the same child. Weekly surveillance for ALRI found 75 episodes in 62 children. Stratified analyses using both approaches suggested father's smoking, and, for girls only, carriage on the mother's back while cooking and being part of a polygamous family were the main risk factors associated with infection: when multiple episodes occurring in the same child were excluded, not having a health card was an additional risk factor in children over a year old. Multiple logistic regression modelling of data from both approaches, including each of these risk factors and sex, age, village and season, suggested father's smoking, carriage on the mother's back while cooking and being part of a polygamous family increase risk of ALRI, the latter two for girls only. The analysis excluding multiple episodes in the same child also suggested that not having a health card is a risk factor for children aged 1-5 years. The difficulties in interpreting these findings are discussed.