Browsing by Author "Kimaiyo, Sylvester"

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    Blood pressure level impacts risk of death among HIV seropositive adults in Kenya: a retrospective analysis of electronic health records.
    (BMC Infect Dis, 2014-05-22) Bloomfield, Gerald S; Hogan, Joseph W; Keter, Alfred; Holland, Thomas L; Sang, Edwin; Kimaiyo, Sylvester; Velazquez, Eric J
    BACKGROUND: Mortality among people with human immunodeficiency virus (HIV) infection is increasingly due to non-communicable causes. This has been observed mostly in developed countries and the routine care of HIV infected individuals has now expanded to include attention to cardiovascular risk factors. Cardiovascular risk factors such as high blood pressure are often overlooked among HIV seropositive (+) individuals in sub-Saharan Africa. We aimed to determine the effect of blood pressure on mortality among HIV+ adults in Kenya. METHODS: We performed a retrospective analysis of electronic medical records of a large HIV treatment program in western Kenya between 2005 and 2010. All included individuals were HIV+. We excluded participants with AIDS, who were <16 or >80 years old, or had data out of acceptable ranges. Missing data for key covariates was addressed by inverse probability weighting. Primary outcome measures were crude mortality rate and mortality hazard ratio (HR) using Cox proportional hazards models adjusted for potential confounders including HIV stage. RESULTS: There were 49,475 (74% women) HIV+ individuals who met inclusion and exclusion criteria. Mortality rates for men and women were 3.8 and 1.8/100 person-years, respectively, and highest among those with the lowest blood pressures. Low blood pressure was associated with the highest mortality incidence rate (IR) (systolic <100 mmHg IR 5.2 [4.8-5.7]; diastolic <60 mmHg IR 9.2 [8.3-10.2]). Mortality rate among men with high systolic blood pressure without advanced HIV (3.0, 95% CI: 1.6-5.5) was higher than men with normal systolic blood pressure (1.1, 95% CI: 0.7-1.7). In weighted proportional hazards regression models, men without advanced HIV disease and systolic blood pressure ≥140 mmHg carried a higher mortality risk than normotensive men (HR: 2.39, 95% CI: 0.94-6.08). CONCLUSIONS: Although there has been little attention paid to high blood pressure among HIV+ Africans, we show that blood pressure level among HIV+ patients in Kenya is related to mortality. Low blood pressure carries the highest mortality risk. High systolic blood pressure is associated with mortality among patients whose disease is not advanced. Further investigation is needed into the cause of death for such patients.
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    Clinical characteristics and 12-month outcomes of patients with valvular and non-valvular atrial fibrillation in Kenya.
    (PLoS One, 2017) Temu, Tecla M; Lane, Kathleen A; Shen, Changyu; Ng'ang'a, Loise; Akwanalo, Constantine O; Chen, Peng-Sheng; Emonyi, Wilfred; Heckbert, Susan R; Koech, Myra M; Manji, Imran; Vatta, Matteo; Velazquez, Eric J; Wessel, Jennifer; Kimaiyo, Sylvester; Inui, Thomas S; Bloomfield, Gerald S
    BACKGROUND: Atrial fibrillation (AF) is a major contributor to the global cardiovascular disease burden. The clinical profile and outcomes of AF patients with valvular heart diseases in sub-Saharan Africa (SSA) have not been adequately described. We assessed clinical features and 12-month outcomes of patients with valvular AF (vAF) in comparison to AF patients without valvular heart disease (nvAF) in western Kenya. METHODS: We performed a cohort study with retrospective data gathering to characterize risk factors and prospective data collection to characterize their hospitalization, stroke and mortality rates. RESULTS: The AF patients included 77 with vAF and 69 with nvAF. The mean (SD) age of vAF and nvAF patients were 37.9(14.5) and 69.4(12.3) years, respectively. There were significant differences (p<0.001) between vAF and nvAF patients with respect to female sex (78% vs. 55%), rates of hypertension (29% vs. 73%) and heart failure (10% vs. 49%). vAF patients were more likely to be taking anticoagulation therapy compared to those with nvAF (97% vs. 76%; p<0.01). After 12-months of follow-up, the overall mortality, hospitalization and stroke rates for vAF patients were high, at 10%, 34% and 5% respectively, and were similar to the rates in the nvAF patients (15%, 36%, and 5%, respectively). CONCLUSION: Despite younger age and few comorbid conditions, patients with vAF in this developing country setting are at high risk for nonfatal and fatal outcomes, and are in need of interventions to improve short and long-term outcomes.
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    Factors associated with isolated right heart failure in women: a pilot study from western Kenya.
    (Glob Heart, 2014-06) Lagat, David K; DeLong, Allison K; Wellenius, Gregory A; Carter, E Jane; Bloomfield, Gerald S; Velazquez, Eric J; Hogan, Joseph; Kimaiyo, Sylvester; Sherman, Charles B
    BACKGROUND: Small observational studies have found that isolated right heart failure (IRHF) is prevalent among women of sub-Saharan Africa. Further, several risk factors for the development of IRHF have been identified. However, no similar studies have been conducted in Kenya. OBJECTIVE: We hypothesized that specific environmental exposures and comorbidities were associated with IRHF in women of western Kenya. METHODS: We conducted a case-control study at a referral hospital in western Kenya. Cases were defined as women at least 35 years old with IRHF. Control subjects were similarly aged volunteers without IRHF. Exclusion criteria in both groups included history of tobacco use, tuberculosis, or thromboembolic disease. Participants underwent echocardiography, spirometry, 6-min walk test, rest/exercise oximetry, respiratory health interviews, and human immunodeficiency virus (HIV) testing. Home visits were performed to evaluate kitchen ventilation, fuel use, and cook smoke exposure time, all surrogate measures of indoor air pollution (IAP). A total of 31 cases and 65 control subjects were enrolled. Surrogate measures of indoor air pollution were not associated with IRHF. However, lower forced expiratory volume at 1 s percent predicted (adjusted odds ratio [AOR]: 2.02, 95% confidence interval [CI]: 1.27 to 3.20; p = 0.004), HIV positivity (AOR: 40.4, 95% CI: 3.7 to 441; p < 0.01), and self-report of exposure to occupational dust (AOR: 3.9, 95% CI: 1.14 to 14.2; p = 0.04) were associated with IRHF. In an analysis of subgroups of participants with and without these factors, lower kitchen ventilation was significantly associated with IRHF among participants without airflow limitation (AOR: 2.63 per 0.10 unit lower ventilation, 95% CI: 1.06 to 6.49; p = 0.04), without HIV (AOR: 2.55, 95% CI: 1.21 to 5.37; p = 0.02), and without occupational dust exposure (AOR: 2.37, 95% CI: 1.01 to 5.56; p = 0.05). CONCLUSIONS: In this pilot study among women of western Kenya, lower kitchen ventilation, airflow limitation, HIV, and occupational dust exposure were associated with IRHF, overall or in participant subgroups. Direct or indirect causality requires further study.
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    Hypertension and Obesity as Cardiovascular Risk Factors among HIV Seropositive Patients in Western Kenya
    (2011) Bloomfield, Gerald S; Hogan, Joseph W; Keter, Alfred; Sang, Edwin; Carter, E Jane; Velazquez, Eric J; Kimaiyo, Sylvester
    Background--There is increased risk of cardiovascular disease among HIV seropositive individuals. The prevalence of HIV is highest in sub-Saharan Africa; however, HIV-related cardiovascular risk research is largely derived from developed country settings. Herein, we describe the prevalence of hypertension and obesity in a large HIV treatment program in Kenya. Methods--We performed a retrospective analysis of the electronic medical records of a large HIV treatment program in Western Kenya between 2006 and 2009. We calculated the prevalence of hypertension and obesity among HIV+ adults as well as utilized multiple logistic regression analyses to examine the relationship between clinical characteristics, HIV-related characteristics, and hypertension. Results--Our final sample size was 12,194. The median systolic/diastolic blood pressures were similar for both sexes (male: 110/70 mmHg, female: 110/70 mmHg). The prevalence of hypertension among men and women were 11.2% and 7.4%, respectively. Eleven percent of men and 22.6% of women were overweight/obese (body mass index ≥25 kg/m2). Ordinal logistic regression analyses showed that overweight/obesity was more strongly associated with hypertension among HIV+ men (OR 2.41, 95% CI 1.88–3.09) than a higher successive age category (OR 1.62, 95% CI 1.40–1.87 comparing 16–35, 36–45 and >45 years categories). Among women, higher age category and overweight/obesity were most strongly associated with hypertension (age category: OR 2.21, 95% CI 1.95–2.50, overweight/obesity: OR 1.80, 95% CI 1.50–2.16). Length of time on protease inhibitors was not found to be related to hypertension for men (OR 1.62, 95% CI 0.42–6.20) or women (OR 1.17, 95% CI 0.37–2.65) after adjustment for CD4 count, age and BMI. Conclusion--In Western Kenya, there is a high prevalence of hypertension and overweight/obesity among HIV+ patients with differences observed between men and women. The care of HIV+ patients in sub-Saharan Africa should also include both identification and management of associated cardiovascular risk factors.
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    Optimizing linkage and retention to hypertension care in rural Kenya (LARK hypertension study): study protocol for a randomized controlled trial.
    (Trials, 2014-04-27) Vedanthan, Rajesh; Kamano, Jemima H; Naanyu, Violet; Delong, Allison K; Were, Martin C; Finkelstein, Eric A; Menya, Diana; Akwanalo, Constantine O; Bloomfield, Gerald S; Binanay, Cynthia A; Velazquez, Eric J; Hogan, Joseph W; Horowitz, Carol R; Inui, Thomas S; Kimaiyo, Sylvester; Fuster, Valentin
    BACKGROUND: Hypertension is the leading global risk factor for mortality. Hypertension treatment and control rates are low worldwide, and delays in seeking care are associated with increased mortality. Thus, a critical component of hypertension management is to optimize linkage and retention to care. METHODS/DESIGN: This study investigates whether community health workers, equipped with a tailored behavioral communication strategy and smartphone technology, can increase linkage and retention of hypertensive individuals to a hypertension care program and significantly reduce blood pressure among them. The study will be conducted in the Kosirai and Turbo Divisions of western Kenya. An initial phase of qualitative inquiry will assess facilitators and barriers of linkage and retention to care using a modified Health Belief Model as a conceptual framework. Subsequently, we will conduct a cluster randomized controlled trial with three arms: 1) usual care (community health workers with the standard level of hypertension care training); 2) community health workers with an additional tailored behavioral communication strategy; and 3) community health workers with a tailored behavioral communication strategy who are also equipped with smartphone technology. The co-primary outcome measures are: 1) linkage to hypertension care, and 2) one-year change in systolic blood pressure among hypertensive individuals. Cost-effectiveness analysis will be conducted in terms of costs per unit decrease in blood pressure and costs per disability-adjusted life year gained. DISCUSSION: This study will provide evidence regarding the effectiveness and cost-effectiveness of strategies to optimize linkage and retention to hypertension care that can be applicable to non-communicable disease management in low- and middle-income countries. TRIAL REGISTRATION: This trial is registered with (NCT01844596) on 30 April 2013.