Kyara Alfred Ndisi, David G Paulo, Khuzeima Khanbhai, Reuben Mutagaywa, Jerome H Chin
AF is common and underdiagnosed and carries a high stroke risk among elderly outpatients in Tanzania. Opportunistic screening of the elderly for AF in low-resource countries with 1-lead ECG is feasible and has the potential to reduce the burden of stroke.
BACKGROUND: Atrial fibrillation (AF) is the most common cardiac arrhythmia worldwide and is associated with an increased risk of adverse outcomes. Age is an important risk factor for AF with a sharp rise in prevalence after the age of 60 years. Despite a rising share of older adults in Africa, there is a paucity of data regarding AF burden in this demographic.
OBJECTIVE: This study aimed to determine the prevalence, clinical characteristics, and associated factors of AF among adults 60 years and older attending noncardiac outpatient clinics at a tertiary hospital in Tanzania.
METHODS: We conducted a cross-sectional study among consenting adults aged 60 years and older at noncardiac outpatient clinics of Muhimbili National Hospital from June 2021 to February 2022. A structured questionnaire was used to collect sociodemographic and clinical characteristics of participants. They were screened for AF using a smartphone-connected single-lead electrocardiography (ECG) device (KardiaMobile, AliveCor). Probable AF was confirmed by 12-lead ECG. Multivariable logistic regression was used to determine factors associated with AF. Data analysis was performed using Stata version 13 (StataCorp LLC).
RESULTS: A total of 1055 patients were enrolled with a median age of 67 years (interquartile range [IQR] 62-72). AF was detected in 44 participants (4.2%). Only 1 participant with AF was previously diagnosed. Most patients with AF had high CHA2DS2-VASc stroke risk scores with a median of 4.0 (IQR 3-5) and 3.0 (IQR 2-3) in females and males, respectively. Age older than 75 years (adjusted odds ratio [aOR] 3.12; confidence interval [CI] 1.31-7.40; P = .01), being underweight (aOR 8.46; CI 1.44-49.76; P = .018), hypertension (aOR 5.35; CI 2.46-11.62; P < .001), and obstructive sleep apnea (aOR 11.90; CI 4.74-29.88; P < .001) were independently associated with AF.
CONCLUSION: AF is common and underdiagnosed and carries a high stroke risk among elderly outpatients in Tanzania. Opportunistic screening of the elderly for AF in low-resource countries with 1-lead ECG is feasible and has the potential to reduce the burden of stroke.